cane t c =, eS VOLUME 1 oS oo. AND OCEANOGRAPHY ee oa ; wn : - > u pen i er : R. E. Owen, Government PRintey cot tH y ees (1952 fame ; é c ath : abies i a 5 2 SJ Given in Loving Memory of Raymond Braislin Montgomery Scientist, R/V Atlantis maiden voyage 2 July - 26 August, 1931 A KK KK KK Woods Hole Oceanographic Institution Physical Oceanographer 1940-1949 Non-Resident Statf 1950-1960 Visiting Committee 1962-1963 Corporation Member 1970-1980 K KKK KK Faculty, New York University 1940-1944 Faculty, Brown University 1949-1954 Faculty, Johns Hopkins University 1954-1961 Professor of Oceanography, Johns Hopkins University 1961-1975 Proceedings of the Seventh Pacific Science Congress of the Pacific Science Association Held at Auckland and Christchurch, New Jar, 2nd Februaty to 4th March, 1948) 0 0301 0087978 4 a oe UU . Tian te, 4 / mi we VOLUME Ii METEOROLOGY AND OCEANOGRAPHY. WELLINGTON R. E, Owen, GOVERNMENT PRINTER 1952 fe rs, a 7 oo iz x . 0 ta CONTENTS METEOROLOGY Symposium on General Meteorology of the Tropical Pacific : sie Symposium on General a eae od of the Pacific in eee nae mad Higher Latitudes Q 5 . 56 = Symposium on Climatology of ine Paci Recon Symposium on Research Needs and Techniques in acide Mercorolory, OCEANOGRAPHY Reports of the Standing Committee on Oceanography Reviews of Pacific Oceanography Symposium on Underwater Sound and Its Biological rad Oceanographical Applications Symposium on Sedtmemeatom and Cherasitstes of Sea Botton in tthe Pacific Basin Bic Symposium on Physical and Ghenienl Properties fe eerie Ocean Ww ANESIES alc Symposium on Marine Biogeographical Provinces in the Pacific Symposium on Problems of Bipolarity and of Pan-Temperate Faunas Symposium on Problems of Eustatism in the Pacific Basin and Rim Symposium on Wave Analysis and Wave Prediction: Waves and Tsunamis METEOROLOGY SYMPOSIUM ON GENERAL METEOROLOGY OF THE TROPICAL PACIFIC SOLAR ACTIVITY AND AIR-PRESSURE FLUCTUATIONS OVER Eb SOUR E seIEIG. OCHAN By H. P. Bertace, Meteorological and Geophysical Service, Indonesia THE existence of an approximate three-year oscillation in the weather elements of the South Pacific and Indian Oceans is perhaps most clearly demonstrated by a graphical representation of the deviations from normal of the six-monthly overlapping means of air-pressure in the tropical low extending from South India to North Australia. Let us take as such the Batavia air-pressure curve (Fig. 1). In previous publications I have tried to establish a theory of the successive strengthening and weakening of the air and water circulation in the South Pacific Ocean, which would explain the long-period os- cillations considered here. I was led to this theory by three empirical facts— (1) Temperature in our region fluctuates with air-pressure in parallel waves, however, showing a phase lag of seven months. (2) Air-pressure in the permanent high-pressure region of the South Pacific Ocean centred at Easter Island and air-pressure in the region considered here oscillate in balance. If air-pressure 1s above normal in one region it is below normal in the other (Sir G. Walker). (3) Low sea-surface temperatures in our region cause air-pressure to rise, high sea-surface temperatures cause air-pressure to fall. The normal cycle which occurs is probably as follows: if air-pressure is abnormally high in the region Bombay—Darwin, it is abnormally low in the sub-tropic high of Easter Island. Consequently, the atmospheric circulation round this high is weakened. This causes the water circu- lation to be weakened also. The Humboldt current is weakened. Less cold water is driven northward along the west coast of South America. The south equatorial current is weaker and warmer than usual. Temperature in the seas of our region rises. Consequently air-pressure is lowered. Hence when air-pressure is abnormally low in the region Bombay—Darwin it is abnormally high in the sub-tropic high of Easter Island. So the balance has swung from one side to the other, and after another turn the cycle is closed. Theory proves that if the phase-lag between temperature deviations and air-pressure deviations is seven months the period of the oscillation becomes four times seven, or twenty-eight months—that is, 2-3 years. Now, this oscillation would experience the damping of every natural oscillation if it were not sustained by the continuous in-flow of energy from the sun. We may therefore expect that such oscillations as the air-pressure fluctuations at Batavia, here exhibited, will show the influence 4) of the fluctuations in solar activity. We will not discuss here how the fluctuations in solar activity, which are hardly noticeable in the total radiation from the sun received at sea-level, may be strongly reflected in fluctuations of air-pressure as a consequence of motions induced in the higher atmospheric layers where the ultra-violet radiation is absorbed (B. Haurwitz). From a simple inspection of the Batavia air-pressure curve it is clear that air-pressure is depressed during years of many sunspots and rises higher and oscillates more freely during years of few sunspots. I think the situation in its general outlines is clear. The earth possesses, like every oscillator, some fundamental period, perhaps it even shows two, but certainly not many. The sun influences the motion of this oscillator by its energy stream. The earth is like a violin, the sun is the player, its radiation is the bow. And the reason why the resulting music is not continuously the same tone is that the source of energy fluctuates so that the music reminds one of numerous variations on the same theme. I found by trial and error that the fluctuations of air-pressure at Batavia can be reconstructed quite adequately by the application of the following rules :— (1) A high-pressure year follows one, two, or three years after a sunspot minimum year. It appears whenever the sunspot number of the year surpasses 20. It appears three years after the previous high-pressure year, if 20 has not yet been reached. When in the first case the mean sunspot number surpasses 50, the impulse will be called strong. (2) The next high-pressure year follows three, four, five, or six years later. It follows three years later if the mean sunspot number has not or not, yet reached 81 or when the previous impulse was strong. It follows four, five, or six years later when the sunspot maximum has passed and the mean sunspot number has decreased below 81. (3) The next high-pressure year follows two or three years later, two years later whenever the mean sunspot number has decreased below 54. (4) The next high-pressure year follows two or three years later, two years later whenever the mean sunspot number has decreased below 13. There are three points towards which I draw special attention :— Firstly, as already noted by C. Braak, if the period of the oscillation is really three years the fall of the barometer evidently takes only one year, the rise, however, two years. This has been taken into account. The cause probably is that the heating of the south equatorial current when the big circulation is weakened occurs rather quickly, whereas the cooling actually requires the transport of polar water from great distances and is therefore late in showing its ultimate effect. Secondly, between two maxima of air-pressure when separated by an interval greater than three years a secondary maximum is introduced. Thirdly, there are two instances in which two successive vears both show high pressure. The first instance is 1918-1919, rule 2 leaving the case dubious. The second instance is 1944-1945, 6 the first of the rules indicating 1945 and rule 4 indicating 1944 as a high-pressure year. Evidently better can be achieved. However, leaving room for the great number of minor influences which may have disturbed the primary variation, it is astonishing to see how few discrepancies between the actual and the purely constructed curves remain which obviously call for special explanations. Such are, for instance, the eruption of Krakatoa in 1883 and Mount Katmai in 1912, which have caused noticeable disturbances in the more regular variation of air-pressure. The above supports my view that this outstanding long-periodic terrestrial oscillation of nearly three years is almost completely controlled by solar action. This is an important conclusion as it may open the way towards an understanding of comparable pseudo-periodic variations in other parts of the world which so far have remained one of the most intriguing puzzles of the seasonal forecaster. Rules 3 and 4 prove that the wave-length is stretched and compressed between two and three years. Evidently the fundamental oscillation would present a period between two and three years in undisturbed conditions. This is in accordance with theory. Finally, we have to answer the question why harmonic analysis emphasizes, as was shown by H. J. de Boer, a mean period of 3-4 years—the same period that was found by H. P. Berlage from tree-ring measurements back over four centuries—although it has no physical reality. There is every reason to assume that the shortest waves lose their individuality in this operation, two crests or depressions coming in very quick succession simply being counted as one. Different facts thus lead to one point of view. The above rules of interaction are so simple that we may hope to be able even before long to interpret them together by some physical principle of interaction between earth and sun. DISCUSSION At the conclusion of the paper an interesting discussion followed, one of the chief contributors being Mr. C. H. B. Priestley, who remarked that Dr. Berlage was the first one to have given a physical explanation invoking the time-lag between air-pressure and _ sea-temperature fluctuations for the existence of the three-year southern oscillation. In answer to a question by Mr. MacKenzie about the periodic devia- tions of the Humbolt current from the Peruvian coast, Dr. Berlage expressed the view that the seven-year period simply resulted from a doubling of the more fundamental 3-4-year period. In reply to a question by Dr. Andrew Thomson, Dr. Berlage said that there were very few observations of sea temperature along a line from Chile to Indonesia, so that a check on the theory could not in this case be obtained. Mr. Simpson questioned the explanation of the time-lag given by Dr. Berlage and asked whether it could not be the effect of local sea-water circulations. In reply to a question by Mr. Hutchings, Dr. Berlage said that the fluctuations of temperature were of the right order of magnitude to account for the changes of pressure, but no calculations had been made as to the precise amount. a Nees eSees| Wad aan ial eres] ter normal The dotted curve is a theoretical deviations from the the f monthly means of air-pressure at Batavia. one derived from the annual in this paper. oO means il. alll) overlapping IG. . to the rules mentioned o =) ccordin sunspot numbers a (o6) ABR TAL WHRARHER RECONNAISSANCE IN THE PACIFIC By Major WILLIAM S. BaRNEy, U.S. Air Force AERIAL weather reconnaissance is a relatively new method of gathering meteorological data. The need for aerial reconnaissance became apparent during World War II when many areas were cut off from the normal exchange of weather information. In the latter years of the war great loss of lives and military property occurred due to the lack of proper information concerning existing weather conditions. In addition to the loss of information from areas occupied by enemy forces, the Pacific theatre of operations recognized the need for aerial reconnaissance due to the sparse network of land and surface vessel reporting stations. To meet the military requirements for additional weather data the Allied Powers resorted to aerial reconnaissance. This was necessary to ensure successful air operations, landing operations, and security of naval warships and Army and Navy transports. As the war progressed, aerial reconnaissance gradually improved, and, through the lessons learned in the first few years, aerial reconnaissance has now been developed into a dependable and scientific method of obtaining weather data. In an attempt to fill in the gap between the land stations, weather ship reports and in-flight aerial weather reports from both commercial and military aircraft, the Air Weather Service of the United States Air Force has established a system of aerial reconnaissance flights emanating from Guam, Marianas Islands, and which covers the south-western and western and north Pacific areas. I will go into detail on these special flights a little later on in my discussion. One of the main reasons for aerial reconnaissance in the Pacific is to locate and investigate typhoons. The relatively few land weather stations in comparison with the immense water areas surrounding them permits the development of strong typhoons before a land station is aware of their formation, and the further lack of an extensive network of reports makes their location and their movement uncertain. Aerial weather reconnaissance is the most expensive method of gathering weather information; however, it is felt that aerial weather reports will enable forecasters to make more accurate predictions on the formation, intensification, and movement of tropical disturbances and typhoons and will increase the safety factor for ships at sea, land installations, and commercial carriers. The cost of aerial reconnaissance pays for itself in the saving of lives and property, both stationary and mobile. To obtain the best possible aerial weather observations a great deal of time, thought, and money has been put into the problem. First of all, aircraft to be used had to be selected for their range, altitude, crew comfort, speed, and economy. During the war economy was not a major factor ; therefore aircraft utilized were generally the bombardment and fighter type. Due to decrease in aircraft manufacture at the close of World War II aircraft which were to be utilized in aerial reconnaissance were drawn from depots where large stocks of combat aircraft were stored. Therefore to-day we are using B29 superfortresses for weather reconnaissance missions because they have the greatest range of aircraft available for the purpose; also they are capable of flying the desired altitudes without discomfort or increased fatigue to reconnaissance crews. The B29’s now utilized have been modified into a flying weather observation station. This modification consists of installation of a 9 psychrometer, an aerograph, special work table for the observer, and the addition of newer types of radar and radio equipment in the aircraft. These flying observation stations also carry a radar altimeter in addition to standard pressure altimeter. Numerous types of instruments to assist in air navigation are required, as reconnaissance aircraft, when flying fixed track missions, may not deviate from prescribed altitude and course for weather causes. For example, as a computation of winds at various altitudes is an absolute necessity, equipment must be available in the aircraft whereby the navigator may obtain double drift winds when the surface is visible, by Loran when flying in clouds, and by radar when adjacent to chains, atolls, and isolated landmarks and Loran coverage is not available. Secondly, the weather reconnaissance crew must be a very well- trained team which must function as such in order to ensure rapid and exact observations as well as rapid means of communication to centres where the data may be disseminated as rapidly as possible. Pilots, navigators, radio operators, engineers, and radar operators have all been extensively trained and are among the best in the United States Air Force. General requirements for pilot co-pilot combination calls for a minimum of 2,000 hours in four-engine aircraft. Combat or transport experience is desired. As some tracks flown are over a distance of 3,000 nautical miles where no land or land mark is available, navigators must be extensively trained in dead reckoning, radar navigation, and celestial navigation. In flying at high altitudes where ground speed often _ approaches or exceeds 300 miles per hour the navigator is required to calculate an exact position, wind direction, and ground speed at the next fixed point as well as track made good every twenty minutes. Flying inside typhoons does not eliminate this requirement. As reports are frequently relayed to one or more stations every twenty to twenty-five minutes and observations generally include a minimum of fifteen five-digit groups, radio operators must be capable of air-to-ground communication where the rate of communication desired seldom falls below twenty words per minute. The radio operator must be familiar with all air-borne radio equipment as lack of communi- cation with ground stations eliminates any value which observations taken synoptically may have. Also the radio operator must be well trained in procedure and have expert knowledge of all radio networks, both American and foreign, in case alternates are required. As all missions are flown over water areas during fair and foul weather the proper functioning of aircraft power plants and the utilization of fuel is of paramount importance. For this reason aircraft engineers have been extensively and thoroughly trained so that long missions may be flown with the greatest possible saving in fuel and engine wear and yet obtain maximum cruising speeds. Radar operators must be thoroughly familiar with all types of scope interpretation, especially that portion which pertains to clouds, precipita- tion static, and other types of interference. They must be able to guide the aircraft through the centre of tropical depressions and typhoons by interpreting the radar picture they obtain by use of air-borne radar sets. In addition, the radar operator maintains a constant search at all times for extensive or odd types of clouds and atmospheric phenomena as well as any or all air-borne objects, and must be able to inform the weather observer of typhoon quadrants where the greatest precipitation, most intense ground areas, and weakest areas of tropical storms and typhoons 10 are located. In addition, the radar observer must know how to compute ground speeds as well as wind directions and velocities from objects on the surface and, if necessity arises, to compute such wind velocities and directions from clouds when in his area. . Other operational crew members are the two scanners, who are respon- sible for constant observance of the engines and airframe and who report any deviations from normal such as smoke, sparks, flame, or structural failures. Another crew member who has recently become important is the dropsonde technician and analyst. To date such a technician has not been utilized extensively in the Pacific due to imperfections in dropsonde manufacture. The dropsonde technician and analyst is responsible for the release of the dropsonde and recording of the elements transmitted. These elements are the same as those transmitted by radiosonde trans- mitters. Due to increased range caused by the aircraft’s motion as well as winds experienced, the technician must be thoroughly trained and capable of high speed operations. The main position in a weather reconnaissance crew and one not mentioned previously is naturally the aerial weather observer. Current requirements for an aerial weather observer are (1) graduation from a prescribed Air Force meteorological school or from prescribed civilian universities. In addition to graduation from such institutions the aerial weather observer must have served a minimum of one year of forecasting duty for aerial operations. Aerial weather observers are usually commissioned officers or non-commissioned officers of the first two grades. (The equivalent to a master or technical sergeant in the United States Air Force is a chief petty officer or a petty officer first class in the United States Navy or a sergeant-major in air organizations of the British Empire.) Many hours are spent and many missions flown to mould a group of individuals, each a specialist in his own field, into a well-co-ordinated and well-trained weather reconnaissance crew. Around the observer’s position located in the nose of the aircraft and the position normally occupied by the bombardier in combat aircraft are located flight instruments normally made available to pilot, co-pilot, navigator, and radar observer. Besides special instruments listed in the beginning of the discussion, flight instruments such as air speed indicator, remote indicator for navigator’s flux gate compass, pressure altimeter of the Kollsman type, &c., are located. The psychrometer is located overhead and to the right and the aerograph is located forward and to the left. In addition to the instruments listed, a wire recording instru- ment is made available so that readings of various instruments and voice comments of the aerial weather observer’s visual observations may be recorded while the aircraft is flying through areas of intense turbulence and where the interphone must be utilized at all times in maintaining fixed heading, a fixed altitude, proper power settings and reflections of the scanners and aerial engineer. Now turning to actual reconnaissance procedures, I will describe the various types of weather reconnaissance as employed by the weather reconnaissance squadron on Guam, which is responsible for all Air Force weather reconnaissance in the Western Pacific. JI have served with the weather reconnaissance unit on Guam for a period of one year and have flown several missions, bods typhoon and fixed track, with all crews of the organization. 11 The Air Force weather reconnaissance squadron located on Guam is responsible for fixed track reconnaissance, for typhoon discovery and tracking and for other missions relating to weather which the Chief of the Air Weather Service or the Commanding General, Far East Air Forces, may prescribe, either in peace or in war. Fixed track reconnaissance is the type of reconnaissance most com- monly used. This type of reconnaissance gives the greatest possible amount of synoptic information, both at the surface and aloft, ana actually furnishes a basis whereby most typhoons or tropical storms are discovered in the Western Pacific. Fixed track missions performed by the weather reconnaissance squadron are known as Vulture tracks. Weather observations on Vulture tracks are made and transmitted every 100 nautical miles. Observations include time, position, wind, temperature, surface pressure or height of 700 or 500 millibar level, clouds including types and the height of tops and bases, state of sea, present and past weather, &c. A cross-section is made while in flight showing all such information pictorially in addition to the weather log. Upon return to operating base the observer immediately makes a post-flight summary from observations made in flight and descriptions and positions of areas where he suspects the formation of tropical storms. This post-flight summary is distributed to all sub-centres in the typhoon network and to all stations responsible for forecasts over the areas. At present the requirement is for three such tracks to be flown daily to the north, south-east, and south-west of Guam. Throughout the world the United States Air Force maintains four reconnaissance squadrons, which are constantly engaged in obtaining synoptic data from areas where reports were formerly denied. The organization based on Guam is the 514th Reconnaissance Squadron, Very Long Range, Weather. In Bermuda the 373rd Reconnaissance Squadron is located and is responsible for synoptic reports from the Western Atlantic as well as hurricane reconnaissance in that area bounded on the south by the Equator, on the north by the Labrador current, on the east by the Azores, and on the west by the short line of North America. In Fairfield-Suisun, California, the 374th Reconnaissance Squadron is located and is responsible for Stork and Lark flights over the Eastern Pacific Ocean. The 375th Reconnaissance Squadron is located in Alaska and is charged with reconnaissance of the North-east Pacific Ocean by Loon and Albatross flights and for the Ptarmigan flights over the Polar ice cap and the North Pole. The other types of reconnaissance which the Air Force is responsible for is typhoon reconnaissance. Typhoons are normally discovered from reports made by aircraft flying fixed track from the north, south-east, and south-west of Guam. Indices normally associated with tropical cyclone formation and readily indicated by reconnaissance reports are : change in wind direction, increased swells and whitecaps, cloud types, fall in surface barometric pressure, decrease in the height of the 700 millibar level, &c. As most weather in the tropical Pacific area is generally of the same type from day to day any departure from normal is reported and is generally viewed with apprehension. Close communication with land forecasting stations must be maintained at all times in order that reports may be rapidly evaluated and disseminated to all interested agencies. Within a few minutes after an aerial observation is made the report has been received at the typhoon warning centre or sub-centre. 12 The designated typhoon warning centre of the Far East Air Forces respon- sible for typhoon warning in the Pacific area is located at Harmon Air Force Base, Guam, Marianas Islands, and sub-centres are located at Clark Air Force Base, Luzon, Philippine Islands; Kadena Air Force Base, Okinawa, Ryukyus Islands; Haneda Air Force Base, Honshu, Japan and Hickam Air Force Base, Oahu, Territory of Hawaii. The typhoon centre is responsible for the initial detection of tropical storms and for the preparation and distribution of advisories of tropical storms and typhoons, the assignment and transfer of forecast responsi- bility to various sub-centres, forecasting the position and direction of tropical storms or typhoons and the preparation and distribution of typhoon bulletins to weather stations, and of forecasts to major Army, Navy, Air Force, and civilian agencies. Throughout this discussion the words “ tropical storm ”’ will be used to describe all depressions where the wind velocity is over 27 knots but less than 66 knots. ‘“‘ Typhoon” will be used when winds are over 65 knots. Once a tropical storm or depression is suspected over any particular area the typhoon centre on Guam analyses all available data and decides whether or not reconnaissance for the following day should be diverted from a fixed track mission to reconnaissance of the suspected tropical storm. Very close contact and co-ordination must exist between the typhoon centre, the reconnaissance squadron and the appropriate naval agencies in order that flight capabilities for the following day may be determined and available aircraft utilized to the fullest extent. If an intense tropical storm is suspected or forecasted, then the availability of aircraft over a period of several days must be considered as the main- tenance of aircraft flying long missions at high altitudes is difficult. Therefore, conservation of aircraft in commission must always be considered. If the typhoon centre decides that typhoon reconnaissance is required for the suspected tropical storm and the unit is capable of such recon- naissance, crews are alerted and the aircraft made ready for flight. Pre- flight of aircraft, briefing of crews, and other preparations for a long and hazardous flight require from two to three hours ; therefore, extreme care must be exercised to ensure that sufficient daylight hours remain to pre- pare for flight and then fly to the suspected tropical storm and complete the required reconnaissance. Night reconnaissance has been attempted, and with present equipment has proven not as satisfactory. It has been the policy of the Air Weather Service in the Pacific to obtain two fixes daily on tropical storms. To obtain the most complete information which will better aid in forecasting movement and intensity and to furnish the latest possible information concerning the location of tropical storms, reconnaissance is normally completed in the early daylight hours and the late afternoon. It is not unusual for an aircraft to depart at midnight to complete early morning reconnaissance on a tropical storm ; neither is it unusual for aircraft completing late afternoon reconnaissance to land at midnight or the early morning hours. The choice of co-ordinates for reconnaissance over the area adjacent to the storm centre will be governed by several factors such as opera- tional limits of the aircraft, hours of daylight remaining, and the position of the tropical storm as related to regularly flown tracks. The typhoon centre or sub-centre requesting reconnaissance will generally request certain areas to be reconnoitred adjacent to the storm centre before d 13 flight time. In addition, the typhoon centre or sub-centre planning the mission always requests that the mission be flown at an altitude and by the method which will provide the most useful weather data for their particular need. Reconnaissance procedures involving tropical disturbances are such that two procedures are actually used, depending on whether investigation of a storm or typhoon is to be made. In storm or search reconnaissance the flight altitude to the storm area will be made at 1,500 ft. Flight altitude within the storm area is the pilot’s choice within feasible operational limits. Upon entering the circulation of the storm a heading will be maintained that will keep the wind to the left of the aircraft or at an angle of 90° from the wind-flow. If the wind is due west the heading will be north. If due east the heading will be south. Such a heading will normally take the aircraft to the storm’s centre. However, if the centre of the storm is difficult to locate an alternate plan is used. This method is to assume a heading with the wind so as to partially circumnavigate the storm. To do this a heading with the wind is assumed, and this heading maintained until the wind has backed to 40 or 50 degrees from the tail and to the right of the aircraft. Then the aircraft's heading is changed so as to again fly parallel with the wind until the wind again backs 40 or 50 degrees from the tail and to the right. This procedure, if accomplished on from two or four legs, will enable the navigator to fix the centre by triangulation. The aircraft will then proceed to that point and reconnoitre until the centre is definitely established. When this is accomplished-a fix will be obtained and a complete observation made. The aircraft will then leave the centre and complete the circumnavigation of the storm. This is usually done at a radius of from 60 to 100 nautical miles of the centre. Circumnaviga- tion will be made through 270 degrees so as to make observations at four points equidistant from the centre and to the north, south, west, and east of the centre. This ensures that all quadrants are covered and gives information needed by the forecaster in predicting rate and direction of movement. It is true that navigation error due to frequent heading changes and rapid wind shifts will make this method difficult at times, but will generally afford the desired information. After completing the circumnavigation the aircraft proceeds, if opera- tionally practical, to the nearest staging base along the storm’s expected track and at an altitude of 1,500 ft. If this is not feasible the aircraft will proceed from the storm in a direction predetermined by the typhoon warning centre and which will give the forecasters the most useful recon- naissance prior to return of the aircraft to the staging base. Flights are so planned as to provide weather data to the limit of the storm’s influence. In reconnaissance where a typhoon is known or suspected to exist the flight altitude to the typhoon area will be made at the 700 millibar level. Observations will be made every 100 nautical miles to the typhoon area. Within the typhoon, observations will be made every twenty minutes, or at prescribed positions and/or when weather encountered warrants such observation. Upon entering the area of the typhoon the precedure is the same as for a storm. However, at the 700 millibar level the use of radar, pressure differential, and visual observation of cloud formations, when possible, simplify this procedure. 14 Upon reaching the centre or the “ eye ”’ the weather observer makes a complete observation. Particular care is taken in computing the height of the 700 millibar level. An effort will be made to determine the slope of the centre if a slope exists. From radar scope readings the weakest quadrant is determined, and the aircraft then departs the centre through that weakest quadrant to the radius of 50 or 60 knot winds, where a spiral descent and sounding is made. The typhoon will then be circum- navigated, using the same procedure as in the case of a storm. To better evaluate the equation evolved by Bjerknes and Holmboe the typhoon should be circumnavigated in the area of typhoon force winds. This will vary, of course, but in all events circumnavigation is made as nearly symmetrical as possible. The best radius to utilize is the one which places the track of circumnavigation between the inner ring of cumulo- nimbus and the outer ring of towering cumulus. The relative intensities of the quadrants is obtained by radar or actual flight and reported to the typhoon centre. As in fixed track reconnaissance, coded reports are relayed at all times plus such plain language messages as are required to present the proper weather picture. Data transmitted includes temperature, surface winds, maximum surface winds, cloud types and amounts, relative numidity, present weather, past weather, turbulence and any special phenomena observed, such as icing or lightning. A cross-section is made showing cloud type and amount of weather, turbulence, icing level, wind direction, and force with the observation positions labelled giving position in degrees and tenths. After return to operating base the observer immediately makes a post-flight summary from information obtained while in flight. Post- flight summaries give a narrative of the weather encountered and a description of the tropical storm or typhoon. Post-flight summaries are given the same dissemination as in-flight typhoon reconnaissance reports, and are extremely valuable to the forecasters who are responsible for typhoon warnings. It is a common belief that aerial weather reports are of less value than surface reports. This belief not only exists among laymen but also among large groups of trained meteorologists, and it is frequently difficult to dispel their ideas concerning the value of such reports. However, after a season’s work in areas where reconnaissance reports are frequently the only ones available, they become adamant about the need for more and more weather reconnaissance reports. Regardless of this, the fact remains that reconnaissance reports are extremely valuable not only for their timeliness, mobility, and frequency, but because such observations are what may be called three dimensional. To the observer on the surface observations above the lower stratus deck are impossible to take. The surface observer cannot observe the various clouds above such a level, and therefore has little conception of the many cloud decks, their configuration, and their direction of movement. The only method of upper air observations during poor weather are rawin or radiosonde, and these are frequently not usable or incomplete due to high winds limiting the time of observation and other atmospheric - phenomena, such as static interference hindering the run. 15 Most arguments against reconnaissance reports (other than high cost) are that such reports are usually inaccurate. Arguments such as these are a carry over from previous years when aerial navigation was accom- plished solely by dead reckoning, celestial and radio means, or a com- bination of all. By use of long-range navigation (LORAN) it is possible to fix positions within 1 to 5 miles of the actual and with such frequency that other methods are seldom used. In case of LORAN failure, air plot to a fixed position and recomputation will give position to within 20 to 30 miles. Considering the scale of our present synoptic charts, both are negligible as far as practical forecasting is concerned, as the centre or aeevic 2 of a well- developed typhoon will generally have a diameter as large as the maximum navigational error. If the argument is advanced that such error is too great it can be truthtully said that errors arising from triangulation fixes from surface reports are much greater due to the fact that the gradient wind must be ascertained in order to actually obtain a fix from triangulation and also the accuracy of a triangulation fix is directly proportional to the symmetry of the typhoon. The degree of error in wind computations seldom exceeds 15 degrees and 5 knots, and when multiple drift winds are obtained using modern drift equipment the error is much less. Due to rapidly changing directions and velocities near typhoon centres actual winds are difficult to obtain. Radar fixes are valuable in wind computations as the wind is vectorially computed by use of true airspeeds and headings compared with the fix. However, the degree of accuracy in such computations is directly proportional to the distance between fixes up to the neighbour- hood of 100 nautical miles. Some error does exist in such computations, as stated previously, due to the ever-changing directions and velocities found in typhoons, and the error increases with distance. The pressure differential or Bellamy method is fairly accurate in giving cross-wind drift components by comparision with true airspeed, and when ground speed is ascertained by radar fixes wil] give a fairly reliable wind reading. In all instances, though, when flying at angles to isobars the varying Jirections and velocities make extremely accurate wind computations difficult. Actually the observation of the ocean’s surface gives the best indication of wind velocity as the observer soon learns to associate wind velocity with types of white caps, sea swells, patches of foam, or complete obscurement of the surface by froth. With the centre accurately determined by a LORAN fix the direction of wind near the centre is not too important ; however, knowledge of the velocity is of paramount importance in typhoon warnings, but the fact remains that precautions for an 80-knot wind would be about the same as for one of 90 knots, and if it can be said that the velocity is over 75 or 80 knots, and such observation is correct, the warning service is more than adequate. In storms which have not reached typhoon intensity wind velocities can be computed to the nearest 5 knots as cloud covering is usually such that an increase or decrease in altitude of 100 feet will allow a multiple drift computation. True altitude, temperature, humidity, and pressure readings are exceptionally accurate as they are scale or scope readings or mathe- matical derivations of both. Maximum errors are 50 ft. in altitude, one degree Centigrade of temperature, 5 per cent. of relative humidity, and at low levels surface pressure is computed to the nearest millibar. 16 Accuracy of visual observations of clouds, weather, visibility, and state of sea depends on the observer and are generally more accurate than a surface observation. The aerial observer usually has a better picture of the weather as he can better report the cloud structure, the cloud heights, their thickness, &c. Entering a typhoon for the first time is an experience few people forget. This is especially true of a well-developed typhoon. Normally you have been flying for from twenty to thirty minutes on instruments with the sound of heavy rain beating against the fuselage almost eliminating the noise of the motors. Suddenly the aircraft breaks through the heavy dark clouds into the clear, similar to stepping from a dark cellar into midday. The sun will be shining, usually through a thin veil of cirrus or high alto stratus. My first experience in entering the centre of a typhoon was just at sundown. The effect was rather startling. We were suddenly confronted by the most weird sight we had ever seen. There was every type of cloud imaginable present, and all were moving in different directions. The sun’s rays reflected from higher clouds and downward from layer to layer gave every colour of the spectrum. Rainbows were everywhere. The centre was between 15 to 20 miles in diameter, perfectly cylindrical in shape. Not even scud clouds marred the centre. The sea surface was calm, but beneath the base of low clouds surrounding the “ eye’ the sea suddenly became a mass of froth. On first sight the impression was that we were flying over a lagoon which was protected from a rough and angry sea by some circular barrier. Ahead of us we could see the lower clouds rotating to the left with foam and spray an estimated 60 ft. in the air. To the right and left of the aircraft the clouds were moving in divergent directions, and the surface had the same characteristics as the surface ahead. We crossed the eye towards the east, encountered a few seconds of moderate turbulence, when we again entered the wall of clouds, and everything again became dark. After flying through the cloud wall and obtaining a double drift we assumed a reciprocal course, and in approximately thirty minutes again broke into the centre. As the heading was almost due west into the sun the appearance of the clouds was even more awesome. The only difference was that the centre had been dis- placed some ten miles north-north-west of its original position. The same sudden jar was again experienced as we entered the cloud wall to the west. Weather instruments on weather reconnaissance aircraft have heretofore been covered rather hurriedly. However, much research and time has been consumed in construction of instruments in order to meet the rigid requirements for such instruments. The four important instruments currently installed are the psychro- meter, aerograph, radio altimeter, and radar set. The ML-313AM psychrometer is an accurate instrument for measuring temperature and relative humidity. The temperature-lag for this instrument is negligible compared to the lag experienced on the standard aircraft thermometer. The ventilator is 18 in. long and 38 in. in diameter, and is installed 4 in. from the outside surface of the fuselage. The pioneer type aerograph AN/AMOQ-2 was especially designed for reconnaissance work and is used to obtain a continuous record of pressure, temperature, and humidity in the atmosphere and the airspeed of the aircraft. 17. This instrument has four major parts, a pressure-air-speed trans- mitter, temperature-humidity transmitter, temperature-humidity ventilator, and the recorder. (a) The pressure-air-speed transmitter measures the pressure of the atmosphere and the air-speed of the airplane, and transmits these values to the recorder. The pressure unit is connected to the static line, and the airspeed unit is connected to both the static and pitot lines. (5) The temperature-humidity transmitter continuously measures the temperature and relative humidity of the atmosphere and transmits these values to the recorder. The transmitter consists of two transmitting units, one actuated by a bi-metal thermometer and the other by a hair hygrometer. (c) The temperature-humidity transmitter is installed in a ventilator mounted outside the plane to the left and rear of the pilot’s position. The ventilator is approximately 18in. long and 24 in. in diameter. (d) The transmitters are electrically connected to the aerograph recorder which makes a continuous record of all functions in four colours, printing once a second on a 100-hour chart roll. This recorder is located to the left of the bombardier’s position. The radio altimeter, SCR-718, is mounted to the left of the bombardier’s position and is adjacent to the pressure altimeter to afford rapid comparisons. The radar set AN/APQ-18, modified to include an A-scope indicator and a longer pulse length, is used on weather reconnaissance aircrait. With this set the beam scans 360 degrees, as compared with only a 60-degree angle to the front on standard models. Another instrument now being perfected is a cloud scope for measuring the base and tops of clouds and will probably be installed in the near future. After all typhoon or storm reconnaissance missions, and in addition to the post-flight summaries, all crew members give a_post-flight narrative of the flight with particular emphasis on their position. These narratives are used in making changes in procedures, instruments, and also are extremely valuable for typhoon analysis, and research as many points are covered that the observer fails to record while flying in severe weather conditions. Following is an aircraft commanders post-flight report of the ninth mission flown reconnoitering Typhoon Beverly. The date was 7th December, 1948. The aircraft commander was First Lieutenant David W. Lykins, United States Air Force. I quote :— AIRCRAFT COMMANDER’S REPORT Vulture “‘ Beverly ” IX 7 December 1948 Aircraft No. 6450 Crew A-1 was briefed at 1000Z, 7 December 1948, to fly tropical storm “ Bever- ly,” fix number nine, using a new method of reconnoitering the storm area. The operations office instructed us to climb to the 700 millibar level after take- off, penetrate the ‘‘ eye”’ of the storm, take a fix in the centre, then make a spiral descent and sounding down to 1,500 ft. and proceed out of the storm on a north- westerly heading to begin the pattern around the storm centre. The pattern consisted of four legs forming a square around the centre, each leg being seventy 18 miles long and oriented north, south, east, and west. In flying the legs the movement of the storm was to be taken into consideration as the pattern progressed, to keep the legs approximately 60 miles from the centre. It was believed that information determined from this pattern would aid in more accurate forecasting of the movement of the storm. After the briefing the crew ate dinner and returned to the aircraft to load personal equipment. At 0300Z I had received my ATC clearance from North tower and I started the take-off run. When I was airborne with the gear and flaps up I made my initial contact with Guam control. There was no reported traffic so we were cleared from control. The instructions were complied with and a heading of 270 degrees was taken up. At approximately 0500Z there was discernible on the horizon a vast coverage of cirrostratus at about 30,000 ft. This indicated to us the presence of the storm, verified by the south wind and slight swells that were perpendicular to our flight direction. The wind was increasing and the swells were noticed to intensify. The boundary of the storm area was very distinct as we approached the edge. At this point the surface wind was estimated to be 35 knots from 180 degrees. At 0738Z the surface wind was observed to have increased to 45 knots, and light turbulence was encountered. At 0742Z moderate turbulence was experienced and a stratacumulus ring of clouds was observed extending in a north-south direction for a distance of about 100 miles. Scattered lightning was detected. An undercast of approximately 7-9/10 stratacumulus was below us and the surface wind was observed to have increased to 60 knots. The outside air temperature remained 10 degrees centigrade, the same as before entering. Moderate rain was encountered at 0756Z, the surface wind increased to 70 knots and moderate turbulence was encountered. From this point on we were on 100 per cent. instrument flying conditions and the moderate to heavy rain and moderate turbulence persisted until we missed the “eye” and flew south for fifteen or twenty minutes. Because we were on instruments and could not see the surface we could not determine the highest wind velocity in the storm. It is estimated close to 100 knots. As we went on instrument conditions we noticed that we had a good drift correction for hitting the centre satisfactorily, so we held the 270 degree heading relying on the radar observer to be able to see the “‘ eye’’ on the scope. The radar had been functioning satisfactorily, and we had a very competent radar observer operating the set. Approximately fifteen or twenty minutes later the radar observer reported seeing a semi-circular ring of clouds about 25 degrees to the right at about 25 miles range. The same ring was detected to the left about the same distance. Figuring we had drifted to the right of the centre we elected to intercept the left return. We flew until we received a definite pressure rise and decided we had made a wrong choice. To make sure that we weren’t chasing circular rings of heavy clouds on the scope we made a turn to 180 degrees and held it long enough to enable us to see the surface wind. After about ten minutes we saw the surface and saw the wind to be coming from approximately west-north-west. We then headed back for the centre of the storm with the wind off our left wing, allowing 15 to 20 degrees for drift. In approximately fifteen minutes the radar observer reported the “‘eye”’ as being almost directly ahead. At 0906Z we broke out into the most beautiful and well defined “eye ”’ that I have ever seen. It was a perfect circle about 30 miles in diameter and perfectly clear overhead. The sides sloped gently inward toward the bottom from 25,000 ft. and appeared to be formed by a solid stratus layer down to approximately 5,000 ft. From 1,000 ft. to 5,000 ft. were tiers of circular cumulus clouds giving the effect of seats in a huge stadium. The wind was estimated at about 35 knots in the centre. No calm water was seen because of the under-cast. After the navigator had taken a LORAN fix, and the weather observer had taken his observation a sounding was begun to 1,500 ft., using the “ eye’”’ as the let-down area. : When we reached 4,100 ft. indicated altitude, using the pilot’s pressure altimeter, the weather observer ssh ean) me that our actual altitude was 1,500 ft. by the radio altimeter. 19 At this point we leveled off and took up a heading of 305 degrees to leave the “eye’’ through the quadrant that appeared to be the weakest on the radar scope. Before entering the wall of weather surrounding the “eye’’ we turned on all the cockpit lights to avoid being blinded by the lightning that had been observed wihilemim thes “eves As we entered the edge of the “ eye’ we were shaken by turbulence so severe that it took both pilots to keep the airplane in an upright altitude. At times the updrafts and downdrafts were so severe that I was forced down in my seat so hard that I could not lift my head and I could not see the instruments. Other times I was thrown against my safety belt so hard that my arms and legs were of no use momentarily, and I was unable to exert pressure on the controls. All I could do was use the artificial horizon momentarily until I could see and intercept the rest of the instruments. These violent forces were not of long duration fortunately, for had they been, it would have been physically impossible to control the airplane. Since the updrafts and downdrafts were so severe and we were unable to main- tain control of the altitude all we could do was to hold the airspeed within limits to keep the airplane from tearing up from too much speed or from stalling out from too little. After the first few seconds we managed to have the third pilot, who was riding on the flight deck, advance the R.P.M. to 2,400 so we could use extra power in the downdrafts and start a gradual ascent from the area. Neither of us at the controls dared leave them long enough to do it ourselves. The third pilot received a lump on his forehead when he struck the rear of the pilot’s seat, and bruised his shoulder from another source in doing so. Since he had no safety belt he was thrown all over the flight deck. This area of severe turbulence lasted between five and six minutes, and every second during this time it was all both of us could do to keep the airplane at a safe altitude, keep it within safe airspeed limits, and maintain a general heading. It is almost impossible for me to describe accurately or to exaggerate the severity of the turbulence we encountered. To some it may sound exaggerated and utterly fantastic, but to me it was a fight for life. I have flown many weather missions in my thirty months in the 514th Reconnaissance Squadron, I have flown night combat missions in rough winter weather out of England, and I have instructed instrument flying in the States, but never have I even dreamed of such turbulence as we encountered in typhoon “ Beverly.” It is amazing to me that our ship held together as it did. When the severest turbulence subsided we found we had gained an altitude of about 6,000 ft. At this point we decided to climb to 10,500 ft. and proceed directly to Clark Field. It was night time, and since we were shaken up pretty badly this was the most sensible course of action to be taken because we had no way of knowing the extent of any damage we might have sustained. The engineer reported that the booster pumps had all gone into high boost and one generator had failed. The radar observer said that the rear of the airplane was a mess of rubble from upturned floorboards, personal equipment, sustenance kits, &c. The flight deck had extra equipment all over it. In addition, the co- pilot had twisted off a fluorescent light rheostat switch when we hit the turbulence as he was adjusting it. The radar observer reported his camera had fallen to the floor. During the climb the scanners checked the exterior of the ship with Aldis lamps to ascertain any damage sustained. Control cables the length of the fuselage were also checked for obstructions. Everything was found to be in order, except for the afore-mentioned heap of loose equipment. We made contact with Clark Field tower about 80 miles from Clark Field after trying vainly to raise Manila Control. Clark tower cleared us to Clark Field at our cruising altitude, and then Manila control gave us a call verifying Clark tower's instructions. Clark Field was V.F.R. with an unlimited ceiling. We made a spiral descent VFR and landed at 1135Z, concluding 8 hours and 35 minutes of flying time. We logged two hours of day weather time, and one hour and twenty-five minutes of night time, and two hours of night weather time. After my experience in leaving the “ eye’ of “ Beverly ”’ at 1,500 ft. the under- signed has only one statement to make and it cannot be overemphasized. An airplane with human beings aboard should never be required to fly through the ‘“‘ eye’”’ of a typhoon at an altitude below 10,000 ft. Ifa pattern must be flown at 1,500 ft. in the storm area it should be clearly indicated that the area of the “‘ eye” be left at the 700 millibar level and the descent be made at a distance of not less than 70 miles from the centre. Full use of radar equipment should be exercised in avoiding any doubtful areas. ‘ 20 As this report is being written the extent of the damage to the aircraft is still being determined. So far the following damage has been found: a slightly bent vertical fin, slightly warped flaps, tears in fairing joining the wing and fuselage, untold snapped rivets on all parts of the airplane, fuselage apparently twisted around the CFC compartment, and the RF unit in the centre section of the bomb bay was torn from its mountings. A very detailed inspection is being made to determine the full extent of damage. DAVID W. LYKINS, Ist Lt., U.S.A.F., Aircraft Commander. A certified true copy: WILLIAM S. BARNEY, Major, U.S.A.F. DISCUSSION In answer to a question by Captain Brownjohn, Major Barney said that vertical ascending currents of up to 5,000 ft. per minute had been observed in turbulent areas of some typhoons. In answer to a question by Mr. Hutchings, Major Barney replied that warm and cold fronts did not play much part in the actual formation of a typhoon, but did appear later in the development. Temperature soundings in the eye of a typhoon appeared to give higher temperatures than in the surrounding areas. Mr. Simpson presented an interesting observation that often the cirrostratus cloud above a typhoon rises as the centre approaches, but no explanation was offered of this. Dr. Spilhaus observed that very near the Equator typhoons had been noted to rotate in the wrong direction for the hemisphere concerned. Major Barney agreed that this was also the case in his experience in the North Pacific. The question of thunder and lightning in typhoons was raised by Mr. Hutchings, and Major Barney replied that although thunder and light- ning occured frequently, typhoons exhibited surprising changes in the character and intensity of the accompanying electrical phenomena, often in a very short time. Not much was known about these changes. HIVIMRICANES ON: RHE WiESt COAST OF MEXICO By Ronatp L. Ives, Indiana University Abstract Frequency, behaviour, magnitude, and trajectory of Mexican west- coast hurricanes is here outlined, on the basis of information available up to 1948; the known and suspected effects of these hurricanes are discussed ; and the need for further study of these disturbances, both along their trajectories and in areas extending many miles beyond them, is noted. INTRODUCTION TROPICAL cyclones have been reported from most tropical and sub- tropical sea areas, and from the lands immediately adjacent to them. Detailed studies of those in the Bay of Bengal(1), the Australian coastal areas(2), the China Coast(3), and the eastern Caribbean Sea(4) are numerous, extensive, and, on the whole, quite dependable except for obsolescence. In contrast, tropical cyclones on the west coast of Mexico are men- tioned only in the more detailed climatic and meteorological works(5), and, even in these, mention is usually brief and unsatisfactory, due in large part to lack of information. 21 During the last four decades, as a result of careful studies by the Servicio Meteorologico Mexicano, our knowledge of these west-coast hurricanes has been considerably augmented. Within the last fifteen years, as the smaller coastwise vessels have been equipped for radio communication, and the settlements on the Sonoran coast and in peninsular California have been linked to central Mexico by wire and radio, the number of reports of hurricanes, locally known as cordonazos, franciscos, or chubascos('), has more than tripled, so that the Mexican Meteorological Service is now able to plot the trajectories of some major hurricanes in the eastern Pacific with gratifying accuracy. A sample chart, showing trajectories of tropical cyclones in this area during the year 1936, substantially as plotted by the Servicio Meteorologico Mexi- cano, comprises Fig. 1. HISTORY Probably the earliest records of Mexican west-coast hurricanes are those to be inferred from the non-arrival of the annual Manila Galleon(6) ; and from the fragmentary reports of “‘ tempestades ”’ to be found in the ‘Documentos Para La Historia De Mexico(7) ’’. One such description, written in 1730, probably by Cristobal de Canas, missionary at Arispe, Sonora, indicates that hurricane behaviour was known, and at least partly understood, prior to that year(8). Later findings, ably summarized by Hurd(9), show a definite increase in the number of hurricanes reported as the amount of sea travel in the eastern Pacific increased, so that during the past four decades an average of slightly more than six hurricanes has been reported annually. The present hurricane reporting situation, although much improved over even ten years ago, is still far from satisfactory, and has been ably summarized by Hurd “ the ‘ accidental ’ encounter of a ship with a violent tropical cyclone in these waters continues, for scarcely a year passes in which some storm owes the only record of its existence to the passage of a single vessel across its path.”’ If and when the radar tracking procedures, now used in the Caribbean, are expanded to cover also the Mexican coastal waters, this shortage of information will be rectified. FREQUENCY OF TROPICAL CYCLONES Temporal distribution of tropical cyclones in Mexican west-coast waters is still problematical, for the aforementioned lack of data makes any estimate subject to a large possible error. By adaptation of the physicists’ ““mean free path’’ computations, it appears that about fourteen such disturbances occur in an average year, there being a possible error ou plus or minus two in this figure. @ y nines terms, the first two of which are igen variants of “ El Cordonazo de San Francisco ”’ (the lash of St. Francis), are applied to almost any violent wind- storm, whether it is a true hurricane or merely a violent local squall. The term hurricane, variously pronounced, is also employed in the same general sense ; and the term ciclon tropical (tropical cyclone) is commonly used by Mexican meteorolo- gists. There are also a multitude of local terms, derived in part from American Indian languages, by which hurricanes are designated. (Hurricane is probably derived from one of the Carib dialects, its original meaning being evil spirit, or bad medicine.) The term typhoon is heard occasionally in some areas near the Gulf of California, it apparently having been learned from Japanese fishermen. 22 “Aroqooles} ay} JO Suruulsaq oY} }e po}eoIpUI oIe syyUO| ‘93ep pezeVoIpur oy} UC oUROTIINY oY} JO uoTpISod UOOU dy} 9}ZROIPUT SIaqUINU PsfOAIQ ‘“OUROTX9]AT OOISOTOIO9}0 TI orotAras oy} Aq poqjojd se ‘gg6~T reoh oy} Sulinp volowry s[ppIy ut sor0zoefe1, ouvoTIINy]J—'[ ‘91 | el = a a es a So = ne oos! SATIN SLALVLS SLVWIXOUddV ie) aga SV3uV 9£€61 YVSAA JHL ONIYNG VOIYAWV JZIGGIW NI SAINYOLOALVYHL ANVDIYYNH aNv1 ONVDIXAN ODIDOTONOSLAW OIDIANSS GNV AVAYNNE YSHLVSM ‘sn Wous Bayon “seaSGROl GERRI Gieimn IEEE Soccer: Cas ean eens aoe ESSN SSS GSS ASS SS PO ost ost os") = F oot os 8 Ov Ov ont oz" oe! = 08"! 06 |— : = Sf SS SS aes os1}-—t | SHLNOW AG XSCNIJ oe: ALITIEVINVA TIVANIVY 00% 00'z ool ol os ———__— os ALINIEVINVA TIVANIVY GNV TIVANIVY 3 CREEPER) bY) SASVYAAV WIDISASAO SEED iD WLOL GaqudYODReY 40 ADVLNSDYad ATHLNOW NI S3YNLVYESdW3L NONLVLIdID3ud VNOZIYV VWNA LIYVAVWN AYGVW VIYVN VISI NOILNGIYLSIG ANVOIYYNH HURRICANE TRAJECTORIES From the accumulated records it appears that a large number, and probably a majority, of Mexican west-coast hurricanes are first reported from the eastern Pacific at about lat. 15° N.; long. 100° W. Backward extrapolation of their trajectories suggests quite strongly that they have a common area of origin somewhere in or near the Gulf of Darien, an arm of the Caribbean between Panama and Colombia. Study of a number of these trajectories shows that these storms, near their suspected area of origin, are usually relatively small cyclonic disturbances, which do not become full-fledged tropical cyclones until they have travelled for some distance. A few of the disturbances cross the Isthmus of Panama, usually as strong to violent families of squalls ; more travel northward, on the Caribbean side of the isthmus, gaining violence en route, and cross to the Pacific via the Rio San Juan-Lake Nicaragua gap. In this area they are usually, but not invariably, recorded as strong cyclones, but with winds still considerably below hurricane force. It is usually not until these cyclones have travelled for several hundred miles over the Pacific that they acquire maximum violence and true hurricane characteristics. Although a few of these tropical cyclones acquire trajectories in the general direction of Clipperton Island (lat. 10° 17’ N.; long. 109° 13’ W., approximately), and a few others appear to originate in that vicinity, most of these storms travel roughly parallel to the west coast of Mexico, a few hundred miles off shore, from about long. 100° W. (south of Acapulco) to about lat. 20° N. (west of Cabo Corrientes), few reported hurricanes going far west of the Revilla Gigedo Islands (*). After passing the Tres Marias Islands (lat. 21° 19’ N.; long. 106° 18’ W., approximately), usually to the west, many of the hurricanes recurve, and run ashore on the mainland of Mexico, in the States of Sinaloa or Sonora. | | > TIBETAN _| )): O PLATEAU | : TOKYO Wa pes = ; : ' IWO JIMA raza) \ i HONGKONG (/ N ae | ae oa se N Late Fall, Vinter Ge: | N d early Spri i \ and early Spring Cuarr A: Dashed arrow line-trajectory. Hachured arrow line-gradient air flow. 41 TT pL ben. HIGH ae Z 300 miles of coast 29 23 (5) Central N.S.W. and Northern See LO 3 6 32 11 Victoria (west of moun- |‘ Wa 4 ~- ‘ tains) 23 9 (6) Central and western Tasman Sea bounded by lats. 32° 17 8 11 14 50 18 and 40° S; long. 165° E. |‘ y= ——_ and east coast of Aust- 25 25 ralia (7) Other areas is Bi 5 5 4 3 17 6 u —~- HI sy 10 u | Total sie ae 87 71 56 70 + | ——_ —, —| 284 100 158 126 DISCUSSION In reply to a query by Captain Best, Mr. Lillywhite said that tropical continental air generally moved out from Australia aloft in a north- west to south-east direction. Some of the figures given by Mr. Lillywhite were confirmed by Mr. Kerr, who presented similar results for the north Tasman Sea and Tasmanian region. Captain Best then raised the question as to whether these depressions might possibly develop aloft and not at the surface. Mr. Lillywhite agreed that this was so, and Mr. Hutchings pointed out that the depres- sions of the Lord Howe Island region very frequently developed aloft over Northern Queensland. Mr. Hutchings pointed out that the northerly component in the tracks of these lows indicated that they were possibly of non-frontal origin. SOME MEASUREMENTS OF EARTH TEMPERATURE AND SOIL CONDUCTIVITY IN NEW ZEALAND By J. W. Hutcurncs, New Zealand Meteorological Service INTRODUCTION Ir has often been emphasized that the standard meteorological practice of measuring earth temperatures at a fixed hour of observation such as 9 a.m. fails to take account of the very large diurnal changes that occur near the surface of the soil. It may also be pointed out that these changes are of great importance to agriculture and in many other aspects of the economic life of the country. Moreover, measured values of soil temperature and conductivity are of interest in various geophysical investigations and play an important part in certain meteorological problems involving the exchange of heat between the earth and the atmosphere. Part I—THE OBSERVATIONS AT EARNSCLEUGH Instruments and Site at Earnscleugh As part of the investigation into frost forecasting in Central Otago a Negretti and Zambra mercury-in-steel thermograph was installed at the New Zealand Government Research Orchard at Earnscleugh, and records from this instrument are now available from May, 1947. In installing the bulbs of the thermograph in the earth a short trench 2 ft. or 3 ft. wide was dug, one side of the trench being 3 in. deep and the other side 5in. deep. The removed soil was then carefully filled in so as to be packed around the elements, and the surface of the soil was then pressed down and levelled. A sparse cover of short grass gradually appeared as natural vegetation, and to all appearances the plot could not be distinguished from the surrounding area of ground. Making allowance for natural consolidation of the ground, it was thought that the above procedure would result in the centres of the thermograph bulbs being at depths of 3in. and 5 in respectively in relatively undis- turbed soil with a natural vegetation cover appropriate to climate of the district. These values were later checked by excavation of the elements and careful measurement of their depths. The centres were found to be almost exactly 3 in. and 5 in. below the level surface of the soil. As far as can be judged from working with the records, both ele- ments have given a very satisfactory record of earth temperature. K 50 Results of the Earnscleugh Observations The results of analysing the temperature observations at Earnscleugh are given in Tables 1, 2, and 3. Table 1 contains the mean monthly maximum and mean monthly minimum soil temperatures recorded at depths of 3in. and 5in. respectively as well as monthly mean values of the soil temperature for each depth as calculated from the formula 3 (max.-+ min.). For purposes of comparison the same quantities are also given for air temperature as measured at a height of 4 ft. above the ground in a standard (non-aspirated) Stevenson screen. The outstanding features of these tables may be summarized as follows :— A. At a Depth 31n. in the Soil (Table 1) :— (1) In the summer months the mean maximum soil tem- peratures are considerably higher than the mean maximum air temperatures. For example, in January the mean maximum soil temperature was 89° F., while the mean maximum air temperature reached only 77°F. In the winter months the mean maximum soil temperatures are rather lower than the corresponding mean maximum air temperatures. Thus in July mean maximum soil temperature was 35° F., while the mean maximum air temperature was 42° F. (2) Mean maximum air temperatures and mean maximum soil temperatures become equal round about April and September. (3) Mean minimum soil temperatures are consistently higher than mean minimum air temperatures, the difference being greater in summer than in winter. Thus in January this difference is about 10° F., while in July it reaches only 5° F. B. At a Depth of 5 in. in the Soil (Table 2.) :— (1) In midsummer there is very little difference between the mean maximum soil temperatures and the mean maximum air temperatures, but at other times of the year conditions are similar to those at the 3in. depth in winter, in as much that the mean maximum soil temperatures are lower than -the mean maximum air temperatures. This difference is greatest in midwinter, being then about 9° F. (2) As was the case with the 3 in. depth, the mean minimum soil temperatures at the 5in. depth are consistently higher than the mean minimum air temperatures, the difference being about 13°F. in January and about 6°F. in July. Table 2 shows the extreme maximum and minimum soil temperatures recorded at the 3in. and 5in. depths, together with the respective maximum and minimum air temperatures for the same days as those on which the extreme maximum and minimum soil temperatures at these depths occurred. Where the same extreme maximum or minimum soil temperature was recorded on more than one day, the average of the corresponding maximum or minimum air temperatures has been taken. This table is very similar to the corresponding Table 1, the main differences being in the absolute magnitudes of the temperatures recorded. Thus the highest soil temperature during the period at the 31n. depth was 102° F. on 3rd January, 1948 (the mean maximum for January is 89°F.), and at the 5in. depth the highest value recorded dL was 86°F. on 5th January, 1948 (the mean maximum for January is 77° F.). Similarly, the lowest soil temperature recorded during the period at the 3in. depth was 28°F. on 6th July, 1947 (the mean minimum for July is 31°F.), and at the 5in. depth the lowest value recorded was 30° F. on 5th, 6th and 7th July, 1947 (the mean minimum for July is 32° F.). In January it appears that the soil temperature at the 3in depth never falls below about 55° F., and at the 5in depth it never falls below about 58°F. In July, however, no soil temperature in excess of 47° F. was recorded at the 3 in. depth, and no value in excess of 39°F. occurred at the 5in. depth. Table 3 shows for every month the greatest, least, and mean diurnal ranges of soil temperatures observed at the depths of 3in. and 5 in. respectively, together with the ratios of the mean diurnal ranges at these two depths. Extreme values are given only to the nearest half degree. For purposes of comparison the mean diurnal range of air temperature derived from seventeen years’ observations in the screen at Alexandra (near Earnscleugh) is included in Table 3. Discussion of the Earnscleugh Results Assuming that heat is transferred in the soil in accordance with the normal theory of conduction, it is possible to use the above results to determine the diffusivity of the soil and thence to calculate its thermal conductivity. If K is the diffusivity, p the density and 6 the specific heat of the soil, then the thermal conductivity is given by the quantity Kp. In this paper most attention is given to the determination of the quantity K. Diffusivity of the Soil The temperature of the surface of the soil will vary periodically with the altitude of the sun and may be regarded as the sum of several harmonics of rather rapidly decreasing amplitude. In these circum- stances the normal theory of conduction of heat shows that each harmonic wave is transmitted downward with amplitude decreasing exponentially with the depth and is subject to_a phase retardation proportional to the depth. Thus with increasing depth below the surface of the soil the harmonics of small amplitude will become negligible, and the temperature may be expressed more and more accurately by a simple sine curve. Assuming a simple sine curve, the quantity K can be computed from the equation K - -. where R, and R, are RJ the daily ranges at depths z, and z, below the surface, z, in our case being 3 in. and z, 5 in. Table 4 shows the result of such calculations for z, — z. = 24in. R and a range of values of the ratio 7 = R. that commonly occurs in practice. On ho From this table we can pass directly from the ratio of the ranges r at the two depths to the corresponding value of the diffusivity K :— TABLE 4 (es Ke (C2G2Ss Units): 2-0 » IeoS) se IO 2-1 bandos 2-2 » les 2°3 5 le) 2°4 mele 2 2:5 5) Jeo 2-6 5 lls 201 59 We 2-8 50 Wey) Results from Earnscleugh show that the ratio of the mean daily ranges at the two depths was very nearly constant for each month of the period, the lowest value of 7 being 2-2 and the highest being 2:6. The average value of y as found from the mean daily ranges for each month of this period is approximately 2-4, and from Table 4 this value corresponds to a value of K equal to approximately 1:2 x 10~° C.G:S, units. This value seems abnormally low, and is, in fact, about one-quarter of that found by Johnson and Davies from a consideration of the ratio of the diurnal ranges observed at depths between | in. and 12 in. in grass covered chalky soil. There is, however, an alternative method of determining the diffusivity of the soil—that is, by means of the change of phase under- gone by the temperature wave with increasing depth. The most convenient way of measuring this phase-change in practice is to note the time-lag between the times of maximum temperature at two specified depths. If L is the lag in seconds, K is readily computed from the T(z, — 2,)? formula: K = ea where as before T is the period (twenty-four a hours or 8-64 x 10* seconds), and z, and z, are the two depths. For the case in which z, — z, = 2” Table 5 is computed from the above formula and gives the calculated value of K for a range of values it IL, TABLE 5 Lag | Kk | Lag kK L (Hours). (C.G.S. Units). | L (Hours). (C.G.S. Units). 193} Soil +e O-8 3:2 Te SexclOm? 1-4 7-0 3°3 1-3 1-5 6-1 3-4 1-2 1-6 5-3 3-5 Ito Tabulation of a considerable number of cases giving the times of maximum temperature at the depths of 3in. and 5in. and also the corresponding lag between the two depths shows that although there is a certain variation among the times of maximum temperature at the two depths the lags are fairly consistent. The mean of all the obser- vations gives the time of maximum at 5in. as 16:4 hours local time, and the time of maximum at 3 in. as 14.9 hours local time. The average lag is thus 1-5 hours for a distance of 2 in. in the soil. 53 From Table 5 it will be seen that if the previously found estimate for the diffusivity is approximately correct, the lag between the 3 in. depth and the 5in. depth should be in the vicinity of 3-3 hours. It thus appears that heat is conducted downwards between the 3 in. and 5 in. levels at a faster rate than is consistent with the normal theory cf conduction of heat:in a solid in as much as the methods depending respectively on the amount of lag and the decrease of daily range between the two levels do not, in this case, yield concordant results. The lag of 1-5 hours corresponds to a value of 6-1 x 10~? C.G.S. units, which is in reasonable agreement with the diffusivity found by Johnson and Davies for chalky soil on the Salisbury Plain. Johnson and Davies found no disagreement between the results of the lag method and the ratio method, but results similar to those found in this paper have been emphasized by Wright, who attributed the discrepancy to the presence in the top layers of the soil of numerous grass-roots which somehow interfere with the normal process of conduction. Part II—OBSERVATIONS IN OTHER LOCALITIES Wazrrenga-o-kurt, Gisborne District In view of the anomalous transfer of heat that has been found to take place in the surface layers of the soil at Earnscleugh it was thought worthwhile to make a brief examination of earth thermograph records from other parts of New Zealand in order to see if any similar phenomenon occurred. The most convenient set of records is that from Wairenga- o-kuri, in the Gisborne district, which give continuous records of tem- perature at 4in. and 8in. below the surface of bare soil. The results obtained at Wairenga-o-kuri for a period of observations during October, 1947, are shown in the self-explanatory Table 6. This table shows that the mean lag is about 3-5 hours, and for a difference of depth of 4in. we find that this corresponds to an average value of 4:5x 10-3 C.G.S. units for K. The mean ratio of the ranges observed at 4in. and 8 in. depth is 2-56, which corresponds to a’ value of K equal to 4:3 x 10-8. Thus in the soil at Wairenga-o-kuri the values of K obtained by both the ratio method and the lag method are perfectly consistent and lead to a very reasonable value for the diffusivity. Here there is no question of anomalous transfer of heat in the soil. Records from other parts of New Zealand have also been examined and tend to show that the transfer of heat is, in general, normal. TABLE | | 3 in. Earth. 5 in. Earth. Screen, | Max. Min. Mean. Max. Min. Mean. Max. | Min. | Mean, | | | | ] | 1948 | | | | | | | | January .. | 89-2 | 62-5 | 75:8 | 77-5 | 66-0 |) 71-7 ies) | 52-9 | 65-0 February Se 84055953 el 6: |) Vousel: O805 Ose tolleiocu | 46-7 | 61-2 March | 74:7 |-63-8 | 64-2 | 66-6 | 56:9 | 61:7 | 69-7 | 45:6 |:57-6 April | 60-9 | 45-6 | 53-2 | 54-6 | 48-2-) 51-4 | 61-9 | 37-7 | 49-8 1947 | May .. 49-1 | 38-6 | 43°8 | 45-1 | 40:5 | 42°8 | 55:5°| 32-7 | 44-1 June Ne OO eeleooe a | SOD) Heroes aadm| ers o wrote) 4 eG | ea OAD nelerS OlnS aula at SHO Ab Soe) low! | 31-9 |.32-3 | 42-1 |. 26°3:/*34-2 August -. | 47:0} 35:0 | 41-0 | 41-0 | 36-5 | 38-6 | 54-0 | 31-4-|.42-7 September 58:1 |, 39-8 | 48-9 | 49-9 | 42-2 | 46-0 | 60-4 | 36-0 48-2 October | 66:1 | 47-2 | 56:6 | 57-8 | 49-3 | 53-5 | 61-5 | Ao 11 | Gls November ats 82°3*:| 55-4 | 68-8 | 70-0) 58-6 | 64-3 | 67-7 | 45°7 | 56:7 December ae) SSI 595 ee) 4G Gul 665: 73-2 | 49-1! 61-2 Earth. 5 in. UINTTUT AL ay pe } vjetIo”d THUUIEX? ay pe}vyari09 "OHULY Aire UW90I0S v meee DH WGI Sv fT HOOD ona oH aA AAA ATA “UINUUITUT AY aUWI9IYX A Ssodur yy ULdYL JO OLY on AAAI COKCORSHMORSDECN ST SSH NAAKAANAAA “UINUIX YY ddI X | 2 TABLE Earth. 3 in, “CUNUITUTY TY poqeferi07 TUNTUTXE any pape]ers0y | ‘a8uvyy Ayre uvoW USCIS) sy © 6f) GO E~ E> 1-H 00 HaARS HASH OS 4 qaakon mn SSGoeis ee oe OMA Oc mal GAS D190 CD on Dot QI & ad oro HS 1 HAS G60 ‘ ienblr! TABLE 3 “TOMLUILUTIA] oulaIy XY “UNIX BJA, ULOIYX | 1948 AAQdLe HOD GON of 1d GO © OnrE DAtan 1) 19 U6) Hh Ono HROD™~O ADaOr dH cA aN A109 S> i> ODr Oo 1D I> DD Ld HH OD Aron Saar —_ > OF ae Soa 34 Of aah ek eB oO jon raf = OMI OGG BRAN ot nan TABLE 6 19 DI Oat nal May June July August September October November December rel SSWS SOSH 1019S g HHAN COONSdHH4 Ne) S2ONOS Sowa Soe7o] >) DAl10DS MMIOrHMOAG ee i el a en en OD | *90URy] IT IF DM 19 S10 O 6 GD HO AqIed DHSmH SoHnnHDOM uPo AAA — Ses NAN 2 so a ‘OBUL YY , a Aue SESS 199997999 S19 a UINUOTUL J Hd ASSN HOD ine) = faa | GOO") STIS tere Ape MOON WIDIDOOSANO WIN UITXY JL THON GO SSS ao Ho Hy H | (o/6} Rs > oO o | H Pe es eeees baleen) t= [iste aR OG 38 OT BOS SO No a4Q8 Be op Oa oO eoGh Ssne HOOD SHat ASaAaAnOAAR RaInNooc real th Oct., 1948. | 09 ~ N et Nd A HILL ill oe SD thus much weaker than that of the more extended land masses of the Northern Hemisphere, where, for instance, the temperatures over the Sahara are higher and their difference against those of the Atlantic Ocean is larger than in Australia. The coolness of the southern summer in higher latitudes is the most marked difference between the surface temperatures in the Northern and Southern Hemisphere. Beyond 40° of latitude the southern atmo- as is now found to be not only near the ground, but to a height of 8 km. 8-10° c. colder than the same latitudes in the Northern Hemisphere. This difference indicates the influence of the different distribution of land and sea upon the heat content of the bulk of the troposphere, but is probably mainly caused by the higher cloudiness and albedo of the Southern Hemisphere. In winter (Fig. 1) the coldness of the antarctic stratosphere and the gradual obliteration of the tropopause towards the end of winter are the most marked features of the temperature distribution. At a level of 16km. the average winter temperature in 78°S. is likely to fall to —80°c. A strong fall of temperature in the stratosphere in winter is found in the North Polar regions, too ; but the average tempera- ture remains still about 10° higher than above the Antarctic. Another interesting fact revealed by the temperature cross-section for the winter is the strong decrease of temperature in the troposphere between 20° and 40° S. A similar large temperature gradient is found in the Northern Hemisphere in slightly higher latitudes on the eastern sides of the North American and Eurasian Continents. This makes it somewhat doubtful whether this temperature gradient is in the south a feature that is characteristic of the whole hemisphere or whether is applies only to the longitude of the cross-section. _ The stratosphere has in winter the highest average temperature in 40-50° S., whilst the temperature is lower towards the Pole as well as towards the Equator. Such a temperature maximum appears in the north, too, but it is more marked in the Southern Hemisphere. With regard to the tropopause, Fig. 3 shows its average height in the southern cross-section and the average for the Northern Hemisphere. The observations suggest a discontinuity in the tropopause around 35° latitude which corresponds to one recently established 1n the Northern Hemisphere. A study of the frequency distribution of tropopause heights confirms the reality of this break. In swmmer the height of the southern tropopause beyond 40° S, is very similar to that of the northern tropopause in winter. Neither our cross-section nor. the. formerly mentioned data from the South Atlantic Ocean corroborate the claim for an extremely low position. of the tropopause in the region of Kerguelen Island (lat. 50° S.). ins In winter the height of the tropopause south of 30° S. is somewhat Jower than in the Northern Hemisphere. The almost identical height at Melbourne (38°S.) and Macquarie Island (54° S.) appears well sub- stantiated. Data from Little America give in winter a height of the tropopause of between 8 and 84 km., almost the same as in summer ; this small difference between summer and winter appears at some places in high northern latitudes, too. The heights of the principal isobaric surfaces show: above 3 km. the disappearance of the subtropical high- pressure belt. . In Swmmer.(Fig..5) the slope of the isobars is steepest near the 300 mb. level. The inclination of the isobars is greater than in the Northern Hemisphere. 58 FIG, 3. In winter (Fig. 4) the inclination of the higher isobars is very strong and increases upwards beyond the 150 mb. level. But the difference beween the southern section and the average conditions in the northern hemisphere is probably smaller-than in summer. Outside the equatorial regions the direction and speed of the wind in the free atmosphere is determined by the equilibrium of the Coriolis _ force and the pressure force. This fact allows the use of the meridional inclination of the isobaric surfaces to find the component of the wind along the circle of latitude—1.e., the so-called “ zonal ’’ component of the general circulation. It must not be overlooked that the zonal wind component as computed from the average distribution of pressure gives - a rather imperfect picture of the actual wind conditions since the meri- dional components of the motion are neglected and components towards 59 tats TUN AA + D1 60 “WEWWAS “VILNIM the east and west partly cancel each other. These restrictions are, however, probably less important in the Southern Hemisphere, where in the higher latitudes the actual flow is likely to be more purely from west to east than in the Northern Hemisphere. Figures 6 and.7 give the average zonal motion of the atmosphere as computed from the slope of the isobaric surfaces. In summer (Fig. 7), in accordance with the stronger inclination of the isobaric surfaces, the zonal wind component is generally stronger in the Southern than in the Northern Hemisphere. At the 5 km. level, for instance, in temperate latitudes between 35 and 65° the zonal component in the south is nearly twice that of the north. Just below the tropopause a maximum of the zonal wind component exists as in the Northern Hemisphere. In winter (Fig. 6) the zonal wind velocities, of the Southern Hemis- phere are only slightly bigger than in summer. The small seasonal difference in the intensity of the circulation which characterises the surface layers in the higher latitudes of the Southern. Hemisphere is found to extend through the whole troposphere. A remarkable feature of the southern cross-section is a minimum of the zonal wind component near 50°S. at the levels above 3km. As a whole the intensity of the zonal circulation in our section through the Southern Hemisphere does not differ much from the average Gonditions) in the Northern Hemisphere. Here again the more fundamental difference between the Northernand the Southern Hemisphere exists in summer rather than in winter. A MERIDIONAL -ATMOSPHERIC CROSS- SECTION FOR AN ~ OCEANIC REGION By J. W. Hutcuines, New Zealand Meteorological Service ae 1. INTRODUCTION At the present time meteorology does not have a generally accepted and adequate theory of the general circulation of the atmosphere. To some extent this is due to the lack of suitable theoretical tools, but it is at least as much due to the paucity of observational data over large areas of the globe. - The lack of observational material is especially striking’ in the Sowers Hemisphere—particularly in the oceanic portions—from which, until very recently, almost no free air observa- tions were available. The aim of this preliminary paper is to bring forward some of the upper air observations that were made in the Pacific region during World War II, and-to set them in relation to the upper air data available from stations in New Zealand. In order to present a more complete picture of the southern circulation some rather scanty Antarctic data are also included. 2.°OBSERVATIONAL MATERIAL ; The following is a brief description of the observational material used in this study. All the temperature data used were obtained by standard Frieze radio-sonde equipment and were evaluated in the standard manner as prescribed in U.S.W.B. Circular P.. While working with-the records it was noticed that daylight flights almost invariably yielded higher - temperatures than flights made in darkness, the difference being of the order of 3°c: It would seem that the greater part of this difference is due to inSolational heating of the instrument and that records from daylight flights are consequently unreliable. In this study only night- time flights have been considered except for the inclusion of a few 62 high-level temperatures from daylight ascents when the daylight and night-time flights at the higher levels showed close agreement. These flights were included to make the high level averages more reliable. The observation stations used in this cross-section were selected so as to lie as far as possible along one meridian, thus trying to avoid the more serious difficulties of interpretation which have arisen with most of the so-called “ meridional”’ cross-sections that have been presented up to date. It will be seen that most of the stations lie within 5° of meridian 170° E., the exceptions being Bougainville (15° W. of 170° E.) and Guadalcanal (10° W. of 170° E.). However, it is not thought likely that this slight deviation from meridian 170° E. will give rise to any fundamental differences in the final picture of the temperature field along this meridian. Again, it will be evident that the cross-section hes in a purely oceanic region and should be relatively free from large-scale effects of continentality. One defect of this section, however, is the scarcity of data south of latitude 46° S., but this seems unavoidable at present. In the future it is possible that the aerological observations made recently by the U.S. Navy far to the south of New Zealand can be used to complete the cross-section in higher latitudes. The only data at present available is the rather scanty Antarctic temperature data published by A. Court in 1942(1). The following table 1 shows the actual dates of the material used. It will be noticed that the months selected cluster closely round January or February for summer and July or August for the winter cross-section, but the actual data used frequently depend on the number of high level flights in each month’s records. TABLE | | | Station. | Summer. | Winter. Wake Island (19° N.) us ee July, 1946. Kwajalein Island (9° N.) .. re June, 1945 (100 and 80 mb. include a few daylight ascents). Tarawa Island (14°. N.) .. | aa June, 1945 (100, 80, 60, | 50, 40 mb. include a few comparable daylight | ascents). Bougainville Island (6°S.) | January, 1945 .. | Jume; 11944. Guadalcanal Island (93° S.) | January, 1945 .. | June, 1945 (150 mb. and , higher include tempera- | : | tures for April, 1943). santo (15$°S.) .. .. | November, 1945 -. | July, 1945. Vila (18° S.) as .. February, 1944 (13 km. | July, 1944 (13 km. include and above include also | June and August, 1944 ; March, 1944) | 16km. and higher in- clude May—September, | 1944). Noumea (22° S.) .. | February, 1944, 1945 (300,, August, 1943, 1944 (300, 200, 100 mb. include 200, 100 mb. include | January, 1944, 1945). | July, 1943, 1944). Norfolk (29° S.) .. | February, 1944-1946 .. | September, 1943 ; August, | 1944, 1945. Auckland (37° S:) .. | February, 1944-1948. .. | August, 1943-1948. Hokitika (43° S.) .. | February, - 1945, peel -| August, 1945-1948. 1948 dane (4G? Sj) oe .. | February, 1944, 1945 .. | August, 1944, 1945. Little America (78° S.) .. | 14 observations, January, 15 observations, Septem- ae - 1940 ber, 1940. 63 3. TREATMENT OF DaTaA As the volume of data made the plotting of every flight impracticable the following method of treatment was adopted. The temperature and humidity were extracted at each standard isobaric surface (following the general plan presented on the W.B.A.N. adiabatic charts), and the average virtual temperatures at these levels were computed. The mean values for each station were then replotted on an adiabatic chart, after which the heights of the standard surfaces were computed and a pressure height curve drawn. The temperature values at standard geopotential were then read directly from the pressure height curve. In some cases only material coded in the 1943 Radiosonde Code was available, and in this case pressure temperature and humidity at the standard heights were averaged and the same procedure used. This method of treatment of the data can be justified, both theoreti- cally and practically, but a practical test is more likely to be convincing. This is shown in Table 2, which gives the heights of the standard isobaric surfaces at Norfolk Island as computed by the above method (A) and also by the more usual method of averaging the heights of the pressure surfaces as computed from each flight (B). The data are for February, 1944-1946. TABLE 2 Pressure Height (A) : Height (B): Surface, Mb. Dynamic Dynamic Metres. Metres. 1,000 Ns Ae ae Va 117 900 re mis ate 1,001 1,000 800 Be a a 1, 970 1,969 700 te a Air 3,053 3,053 600 ahs see Pe 4,276 4,277 500 ie bes a 5,681 5,682 400 as “a ae 7,334 7,336 300 sith es is 9,358 9,359 200 hee in penle2eOiiG) 12,015 Where possible data for the height of the tropopause were obtained by both methods, and good agreement was obtained as long as sufficient observations were available to yield reasonably reliable means. 4. The temperature cross-sections are shown in Figs. 1 and 2 and show the principal features common to all such diagrams. There is no need to describe these well-known features here, but attention may be directed to a few details that are not generally recognized. Although the mean tropopause is drawn as a continuous line it is very probable that there are two tropopauses—tropical and polar— and that there is a discontinuity at a certain latitude. This is clearly seen in the mean sounding for Auckland (lat. 38°.) in winter, where both tropopauses appear with sufficient regularity to appear in the mean temperature distribution. Another fact that has not hitherto been sufficiently emphasized is that in the higher parts of the troposphere there exists in sub-tropical and tropical latitudes a reversed temperature gradient in which the isothermal surfaces slope upward from the Equator towards higher latitudes. Willett(2) has described a similar effect in the North American region in summer as being due to the heating effect of the American Continent, but such an explanation cannot be applied to a purely oceanic region, and the explanation must therefore be considered doubtful. 64 = ° 3—Pac. Congress $0 40 30 EGG 65 20 ats) SUMMER. 20 The highest part of the tropopause shows a marked oscillation in position, according to the season of the year, but even in the winter season it seems to lie in the Southern Hemisphere. This marked asym- metry would seem to be a peculiarity of this region and is probably not a general feature of the southern circulation. It is of interest also to note that in certain sub-tropical latitudes temperatures in the upper part of the troposphere are warmer in winter than in summer. Regarding the seasonal variation of the tropopause it would seem that in this region the tropical tropopause is higher in summer than in winter as is also the polar tropopause. Variations of the latter tropo- pause from winter to summer, however, seem to be somewhat greater. This variation of the tropical tropopause is contrary to the variation given by Willett(2) for the North American region. However, the conclusions reached in this paper obviously need con- firmation by the examination.of a larger number of records. This task is now being undertaken, and the results will be presented as soon as possible. REFERENCES (1) Court, A.: Bulletin of American Meteorological Society, May, 1942. (2) Wittetr, H. C.: Descriptive Meteorology, 1944. HEAVY RAINS IN HAWAII AS RELATED TO IMPORTATION Ole COLD AWN UNLOVE IE By R. H. Simpson, U.S. Weather Bureau, Honolulu (A bstract] Analyses of time cross-sections for Honolulu soundings are considered in relation to flow patterns over the Eastern Pacific during periods of heavy rain in Hawai. It is shown that flow patterns become more clearly related to rain occurrences when analyses are extended into the middle and upper troposphere. This is supported by recent studies of Mordy and Leopold which show conditions at 300 mbs. to be most significantly correlated with the occurrence of general rain. Outbreaks of rain are preceded by importations of cold air aloft which may reach the Hawaiian area either from the north, upon arrival of a polar trough, or from the east in connection with easterly waves. Heaviest rains occur with the simultaneous arrival of cold air from both sources. When cold air aloft streams southward into the tropics and becomes detached from its source, it tends to disappear rapidly through subsidence, but may occasionally collect in a broad pool and persist. It is noted that the latter condition frequently seems to foreshadow the development and westward movement of an easterly wave. WEATHER OBSERVATIONS IN THE ANTARCTIC SEAS By M. Tamura and J. SuGiIuRA, Central Meteorological Observatory, . Japan THE authors were engaged in weather observations in the Antarctic Seas on board the Japanese whaling ship “ Hashidate Maru,” of 10,000 ton, from 4th December, 1947, to 8th March, 1948. The operation field of the ship covered sea area ranging from S. 63° 06’ to S. 75° 41’ and from E. 148° 04’ to W. 172° 08’. The results of weather observations ~ will be summarized below. ‘ 66 PRESSURE (1) Maximum, minimum, and average pressure observed aboard throughout the whaling season were 1,011-7 mb., 951-4 mb., and 985 mb. respectively. Maximum change of pressure in three hours was 6-9 mb: when going up and 7-7 mb. when down. Generally speaking the amount of pressure change in three hours was least in December and increased toward March. However, geographically, it was smaller in the Ross Sea than in.the sea area north of Balleny Islands. TEMPERATURE (2) Maximum and minimum of temperature observed on board the ship throughout the period were 2-7°c. and —6-2°c. respectively. Mean of the daily amplitude of temperature was 1-5° c. to 2:0° c. Mean temperature in the same period was lower by 1-5° c. in the Ross Sea than in the.sea area east of the Balleny Islands. Average humidity was different according to locations, generally ranging between 85-90 per cent. But the humidity in the Ross Sea was around 75 per cent., showing comparatively lower values than in the other sea areas. Maximum and minimum sea surface temperatures, throughout the period were 1-1° c. and —1-6° c. respectively. WINDS (3) Westerlies prevailed in the northern territory of the whaling ground, ranging from S. 63°-S. 65°. No conspicuous difference between the frequencies of easterlies and westerlies in the sea area east of Balleny Islands was observed, and easterlies prevailed in the Ross Sea. The biggest frequency of wind force over the period was four. The smallest frequency of strong winds was experienced in December and increased toward March. Four observations of strong winds exceeding 20 m/sec. were taken in the whaling ground. Thé occurrence date of each and its accompanying weather conditions were as follows :— 1 { i Wind. } Skv | Tendency Month. | Date. | Time. | Latitude. | Longitude.) Press. | C eV. of Direc- | « ondition.| pressure. 3 Speed. tion. 1 | l | ! ewes eS i any; m/sec. | aie Ge 4 19 So GH 2s || 185 1bRS BRIE Ola! Wi. 20-8 Overcast | Ascending. Hebs ee 10 21 $5 70)02) | 2. 179) 00/97 SESsB) 20-3 a : IPE, 3.6 29 08 S. 67 56 | E. 172 42) 974-4. Ss 21-2 Snow .. es WHERE, le 3 12 Sb. G7 05 |) 135 IGG 29} Gites |S, 3359983 = .. | Minimum. I Generally, pressure goes down in the winds from N.E. quarter, and goes up in the winds from S.W. quarter. Average of pressure changes in three hours, classified according to eight points of wind directions, is as follows :— ING ING: 1B, Sale Se S.W. W. N.W. mb. mb. mb. mb. mb. mb. mb. mb. —0O-61 —1:-47 —O-77 —O069 1:24 117 0-44 0:04 67 (4) Frequency of occurrence of sea fog, closely related to the whaling, is given below :— Frequency Region (Lat./Long.). Gane : Per Cent A S. 64-66 E. 148-156 29-2 B S. 63-66 E. 156-164 24-5 C S. 65-70. - FE. 164-180 16-8 D S. 70-75 FE. 180-172 2°5 Above is the result obtained from the records taken aboard the whaling mother ship “‘ Hashidate Maru,”’ while the following is the result recorded aboard another whaling mother ship ** Nisshin Maru.” i ab as - . Per. Cent. By ae .. 9. 63-65 IE. 158=1163 22°3 Cc os .. S. 66-68 E. 166-171 14-0 E Be: .. 9. 66-68 E. 160-164 23° The most frequent fog occurrence was seen in the sea area covering S. 64°-65° and E. 148°-156° showing 30 per cent. And it was 23 per cent. in the sea area covering S. 63°-68° and E. 156°-163°, 15 per cent. in the east of the Balleny Islands, and about 2 per cent., the least, in the Ross Sea. CLIMATE AND WEATHER OF JAPAN By K. TaKAHasui, Central Meteorological Observatory, Japan CLIMATE and weather of Japan have been studied by the author, especially the synoptic. aspects. Seasonal changes such as beginning and ending of summer are not continuous but discontinuous. For example, the temperature rises suddenly in the middle of July and falls suddenly in the middle of September. Such phenomena are found in normal annual change of air temperature as well as yearly annual change. This may be explained as follows. In the middle of July the summer monsoon begins and the frontal zone in front of Tm air crosses Japan towards the north while in the middle of September, the summer monsoon is over and the frontal zone re-crosses Japan towards the south. Rainy seasons of Japan, Baiu in June and typhoon rain in September, are accompanied by the passage of the frontal zone. In Japan we found other rainy seasons, spring rain in March or April, and winter rain in November or December, though they are not as distinct as Baiu and typhoon rain. These rainy seasons occur with the passage of the polar frontal zone in front of Pc air masses coming from the continent as the winter monsoon. In the following table normal dates and standard deviations of the beginning and ending of every season and the synoptic characters of every season are shown. 68 CLASSIFICATION OF SEASONS IN JAPAN on Japan sea coast, stable Season. | Weather Type. | Period. Remarks. } | Spring .. | High and low pass cyclicly, | Mar. 1-+16 | Temperature rises suddenly after weather variable | passage of travelling anticyclone. Early summer | High belt forms, fair and mild .: | April 30 - 8 | Cyclic change of weather over. Baiu .. | Tropical front forms south of | June 5 + 10} Temperature falls, rainy season Japan, rain begins. Summer .. | Southerly monsoon prevails, hot, | July 18 -- 7 | Temperature rises suddenly, some- fair weather, stable | times accompanied by heavy | rains. Fall rain | Tm air mass replaced by Pe, | Sept.11 + 6 | Temperature falls suddenly, some- | raining times accompanied by typhoons. Fall .. | High and low pass cyclicly, weather | Oct. 10 -+ 9 | Rainy weather over continental changes cyclic high develops. Early winter Cold air mass comes to Japan, | Nov. 20 + 10 | Winter type pressure pattern begins | occasional showery precipitation occasionally. Winter Northerly monsoon prevails cold, Dec. 18 + 5 | Temperature falls suddenly after and fair on Pacific coast, snowy passage of cyclone. i} | | | i In this table only an outline of the characters of every season are shown. Studying further we may have results which would be useful for long-range forecasting. The weather of Japan changes cyclically, as a whole, and we found three or four days and seven or nine days periodicity. The short period is caused by the passage of low, while the long period is caused by the outflow. of highs from high latitudes. In summer and winter long periods predominate, and in spring and fall short periods predominate. We experience also thirty-five days periodi- city. Japanese forecasters know that the modes of the weather changes have a yearly character, and similar weather situations appear very often im one year. This is proved statistically, and it is important for long- range forecasting. ON SEA FOG OF ADVECTION TYPE OVER THE OYA SHIO By YosHrHiko TAKAHASHI, Central Meteorological Observatory, Japan INTRODUCTION In June—July fogs are frequently observed at sea along the Kuril Islands and the Pacific coasts of Hokkaido, when-the warm and humid air from the south moves in over the Oya Shio. The weather map in Fig. 1 shows a representative of the pressure distribution favourable to the occurrence of such fog, and Fig. 2 shows the distribution of the water temperature of sea surface averaged for the first ten days of August, 1941. This year the period of the predominance of the Oya Shio has been somewhat late. As frequently as sea fog of advection type another type of fog, or frontal fog, occurs in the same season along the Kuril Islands and the Okhotsk coasts of Hokkaido, when the cold wind from the anticyclone over the Okhotsk Sea or the Bering Sea blows toward these districts. The present paper, however, will be concerned with sea fogs of advection type only. As to the causes of sea fogs it has been known only that as the warm and humid air moves over the colder water and is cooled from below so that its dew point is reached, fog will be produced. But from the physical point of view such a theory must confront many difficulties to explain quantitatively the properties of sea fogs. If the theory be correct, for example, sea fogs would not be much different in properties from 69 75€ 75E 760 162. 4 JUNE 28 , '!944 6h OClear @® Hish Carling AumvenphGenthee o Pat @ Middle « indicates Wind Force. J © Low « Pressure inMillimeters Fic, 1.—Example of pressure distribution favourable to the occurrence of sea fogs of advection type at the sea along the Kuril Islands and the Pacific coasts of Hokkaido. radiation fogs on land, because the latter are also caused directly by cooling of the air from below. But the observations do not show such identity at all. Later Professor 5. Petterssen has suggested the convection theory on the formation of sea fogs of advection type along the west coast of California. The theory is as follows: a stratus layer will be formed under the inversion by vertical mixing or convection in the air under the inversion, the base of the stratus layer coinciding with the condensation level of the surface air. When the condensation level comes down to the surface, or other fog-producing factors are present in the lower portion of the layer, the stratus builds down to the surface and forms a dense fog. The theory of Professor Petterssen might be much better than the old theory to explain the nature of sea fogs, but the theory is still doubtful on account of the following reason: sea fogs are often accompanied by 70 IBERIA Fic. 2.—Sea-surface temperature in the first decade of August, 1941. This year predominance of the Oya Shio was late. (After daily information from ships to the Central Meteorological Observatory.) mist or drizzle whose precipitation amounts to a not negligible quantity, so that there must be upward motion of the air as a whole in order to maintain the upward supply of water vapour and at the same time to suspend growing fog particles in the air. But such ascending motion of the air might not be expected by the convection theory. The present author has suggested a new theory in 1944, the outline of which will be seen in the last part of this paper. This theory has proved the possibility that the warm air moving over the cold water might have ascending component of velocity. THE NATURE OF SEA FoG OF ADVECTION TYPE On the basis of the observations of the present author and many other persons the nature of sea fog of advection type has been summarized below :— _ (1) In June-July and sometimes in August sea fogs of advection type occur frequently in the regions immediately surrounding the Kuril Islands and along the Pacific coasts of Hokkaido, the densest ca 84035" G425"", JUNE IB 1/944, SKY; SLCU, AMT JO WD 1200 > 9 Ss ~ Na §00 x % mK 0 >) nh 400 O Fic. 3. fogs being observed in the area to the south of Central Kuriles, where the Oya Shio is the most predominant. Usually sea fogs are carried in over coastal districts. (2) Moderate breeze is most favourable to the formation of sea fogs, the direction of wind being between south-east and south-west. (3) When the sky is overcast with low or middle cloud, fogs are in many cases dense and stable, and sometimes are maintained for several days or more throughout day and night. (4) When the sky is cloudless or partly clouded, or covered with high cloud, fogs are usually thin in the daytime on account of receiving solar radiation and remain off the coast, but in the evening or at night they become dense and spread over coastal districts, where they dissolve the next day. Moreover, very thin fogs disappear entirely even at sea in the daytime and form again in the evening. (5) Very often sea fog forms at some distance above sea-level. Such fog is usually called stratus, though there is no fundamental difference between them. In the opinion of the present author such stratus is but a special state of sea fog, and accordingly it is better to call it, for example, ‘“‘ high-base sea fog.’’ -But here “stratus” shall be still used according to the custom (see Fig. 4). Sea fog changes frequently into stratus as it dissolves from below or its base rises above sea-level (mostly in daytime), and reversely stratus changes into fog as it builds down to sea-level or to the ground (mostly at night). (6) Sometimes fog or stratus is formed of two or three different layers in piles. Such a single layer often changes into double or triple layer, and reversely double or triple layer often changes into single layer (see Figs. 5 and 6). 72 LEESLRS \SULY £8 ,/GAA SKY Acv, AMT. 3 12.00 | 800 1 4.00 O ra) N ss S VW N Fig. 4 ISh 35m~lPhoy™ JUNE 26,1944. | Sky ;Stcv ,AMT./0 1200 \ RR VT Wi aD ee ac a - &sF - 800 / ML NALNS XNA LL LI ko A 400 0.1 2) fe) Te) Fic. 5.—Example of sea fog of double layer and its vertical structure at Nemuro. 73 SAI2" ~~ GhO6™ JUNE 15, /944.. SKY; SACU 200 400 AVA (= S) W N Ine, Ge Example of sea fog of triple layer and its vertical structure at Nemuro. Double and triple layers occur mostly in the case of double inversions, (see Fig. 6). (7) The top of the inversion observed at Nemuro generally hes at a height of from 200 to 500 m., but in a few cases it reaches a height of nearly 1,000 m. In the case of double inversions the top of the upper inversion is very high ; therefore it might be considered that a very high single in- version forms through the disappearance of the lower inversion of a double inversion (see Fig. 3, where a trace of the lower inversion will be seen). (8) Frequently mist or drizzle accompanies dense fog or stratus, precipitation amounting often to more than 2mm. per hour, and the average size of drops being over 0-2 mm. in diameter. (9) When fog or stratus is accompanied with drizzle, minute rain droplets are produced in the middle portion of the fog or stratus layer by the growth of fog particles, and they begin to fall from there. For the first some distance of falling they grow still larger with falling, but when the layer of unsaturated air is present below, falling drops diminish in size and in number on account of evaporation, and sometimes they cannot reach the surface (see Fig. 7). (10) Wind direction remains almost constant with height, except in the first 100 metres, where wind is apt to turn westward on account of the frictional effect of the ground (see Figs. 3-5): But in some cases wind changes rapidly westward above the top of fog or stratus layer. 74 JULY Te Hoa AT 420m. 8°42" 9'90™ Ss) 9S AT ZOOM. S ie) 9 9 9 AT THE SURFACE 08S-zW2001 Y3d SdOYUd DONINIW4 40 239 WON 100 120 150 180 220 270 33006 400 DROP DIAMETER IN j* Fic. 7—Example of the variation with height of drizzle accompanying sea fog or stratus. From the diagram it will be understood that the rain-producing layer lies at 200-400 m. above the ground and evaporation layer 0-200 m. Fog situation is as follows: 490 m., top; 490-430 m., density decreasing with height ; 430-140 m., fog; 140m., base; 140-40 m., hazy ; 40-0 m., no fog. (11) The observations at Nemuro show that in many cases the wind gets maximum velocity at a height of from 150 to 500 metres (see Figs. 4-6). This would be owing to topographical effects, but, as the height of maximum velocity generally coincides with the height of the top of the inversion, there might be some other causes. ; (12) The vapour tension of the air above a fog or stratus layer is not low, except in some cases (see Fig 3). (13) In the case of sea fog it is rare that the foggy air on the sea surface or on the ground is completely saturated, except in the case of very dense fog or at night when air temperature falls enough. Moreover, in the fog or stratus layer portions of unsaturated air are present, especially near the top and the base of the layer, and sometimes in the middle part of the layer. Such unsaturation cannot be explained by the depression of vapour pressure due to salinity of fog particles. A NEw THEORY ON THE FORMATION OF SEA FOG An outline of the theory which the present author has suggested is given below. I OV Here we make the following assumptions :— (1) Let H be the height of the friction layer in the atmosphere, and U the wind velocity at that height. H and U are constant. (2) Let A be the Austausch coefficient of the air above the inversion layer. A is constant. (3) Let H’ be the height’ of the inversion. H’ increases through the upward transfer of cooling effect from below, as the air moves over cold water. Denote the wind velocity at H’ by w’. (4). Let A’ be the Austausch coefficient of the air in the inversion layer. A’ is constant. This means that the air proceeds over the area where the water temperature of sea surface decreases rapidly leeward so that the steepness of the inversion is kept constant, for A’ depends closely on lapse-rate. (5) The motion of the air in the friction layer is caused by the eddy transfer of momentum from the steady current of the air above the friction layer. (6) The air is in steady motion. (7) Frictional force at the sea surface is opw,*, where p is density of the air, u, wind velocity at the surface, and o constant. For the ground o will be nearly 0-004, but for the sea surface we shall take it as 0-0005 on account of its smoothness. Now we shall consider the variation of wind velocity with height, when warm air has moved some distance over cold water and the inversion is present. According to the assumptions wind velocity increases linearly with height in each layer from surface to H’ and from H’ to H.. Therefore the boundary condition at the sea surface is U’ — Uy A’ == opt,” H’ and at H’ rele Spot! = We H — H’ lel From these equations we obtain ea LTA pi een Uo el sade ny enero MI Gp Ge - H 7) 2M Ja AN and ; uo =U, +— ptt,” NG Now we shall calculate vertical distributions of wind velocity at two points where, for example, H’ = 400m. and H’ = 500m. respectively. We take here H = 1,500m., U=10m./sec., A = 100 g./cm.sec., AG Oven /emmsecs iandiy)/py— 0-002) er/cmas ) ihenmait siollowsratner Noe Isl’ ==) 4K010) ray Oh == ool may S8C3, 27 Sse U1 Wa /SEC., and for H’ = 500 m. wy = 4:07 m./sec., u’ = 9-04 m./sec. Therefore, we are now able to draw the vertical distribution of wind velocity at these points in a diagram. 76 The results are shown at right in Fig. 8. As seen in the diagram, some retardation of wind velocity takes place in the inversion layer, as the air moves from the first point (H’ = 400m.) to the next point (H’ = 500m.). This causes ascending motion of the air in order to establish continuity. For example, take the distance between two points as 10 km., then the magnitude of ascending component of the air at each height becomes such as illustrated at left in Fig. 8. 15, = G > “10 L 40 : > 3 = ne O05 05. “Sy Y + 0 ° Dolo gte ee ease ESOT TE Wind Ve [Se ity in mysec EiGy or Thus it has been proved that ascending component exists in the air which moves over successively colder and colder water surface and consequently sea fogs are produced in the same way as ordinary cloud. Indeed, sea fogs are much alike to the cloud which is formed in weak ascending current of the air, and accordingly sea fogs should be regarded as a type of cloud which forms at small distance above sea-level and often builds down to sea-level on account of very high humidity of the air over the sea. ; ON THE MECHANISM OF HEAT THUNDERSTORMS AND SOME PROPERTIES OF CUMULO-NIMBUS IN JAPAN By S. SAKURABA, Central Meteorological Observatory, Japan THE heat thunderstorm which occurs most frequently in summer is investigated by aerological data, and some properties of cumulo-nimbus are discussed by the data from a dense network of observation points in the Kwanto District, Japan. Part J—-MECHANISM OF HEAT THUNDERSTORMS To make clear the mechanism of heat thunderstorms or, in recent terminology, air mass thunderstorms, four-hourly radiosonde observations were made from 2nd to 17th August, 1944, at Maebasi, Gunma Prefecture, Kwanto District. 6008, 5000) 4000 3000 2000 TO IS al Sy Gh 7 ta Figure 1 shows the variation of vertical lability determined from the sequent ascents every four hours, where the abscissa denotes the time of observation and the ordinate the labile energy in joules per | kg. air, vertical lability being expressed. by vertical labile energy itself. Here the labile energy is computed by the parcel method widely applied in adiabatic charts, and becomes positive or negative according as the atmosphere is in conditional instability of real latent type or pseudolatent type (Petterssen, p. 62, 1940). The thick lines in the figure denote the energies releasable when a lifting air parcel starts from the ground (which will be referred to as “surface ’’ value later), while the dotted Imes denote the mean values when the parcels start from several higher levels, including the ground level (which will be called ‘“‘ mean” value). They both show parallelism except a few cases. Figure 2 denotes the mean diurnal variation of vertical lability, the maximum being at 14th—16th. 18 = 1 O00 4a S26 20°20 hn IgnG, 2, The analysis of the above result, taking into consideration pilot balloon, surface, and mountain observations, leads to the following conclusions, as to the mechanism of heat thunderstorms and alteration of vertical lability :— (1) Advective Change— (a) Advection of Cold Atr at the Level of Tropopause : The labile energy is very large and exceeds 4,000 joules (mean value). Strong thunderstorm is produced. (0) Advection of Cold Atr in the Lower Atmosphere: The cold air comes from the Japan Sea side over the Joetu Mount- ains, northern border of the Kwanto Plains, and rides over a heated unstable air stratum stagnant in the Plains in daytime. This unstable stratification causes the labile energy of 2,000— 3,000 joules (surface value). Moderate or weak thunderstorm is produced. (c) Advection of Southerly Warm Air: When the fresh southerly warm air invades from the Pacific Ocean side, the stratification becomes suddenly stable. This current is of different nature from local sea breeze. (2) Non-advective Change— (a) Heating From the Ground: The labile energy due to heating alone does not exceed 2,000 joules (surface value) and no thunderstorm is produced, only resulting in the development of moderate or weak cumulo-nimbus. Figure 2 should be interpreted as the mean diurnal variation of labile energy due to surface heating alone. (6) Stabilizing Action of Convection: The labile energy is completely consumed within one to two hours by convective motion accompanying cumulo-nimbus. Therefore, in case of no energy supply, the duration of thunderstorm is one to two hours. 79 As is evident from the above analysis, the lability due to heating alone is not sufficient to cause thunderstorms, but the co-operation of heating and cold air advection is most important for the formation of heat thunderstorms, Roughly speaking, the labile energy due to surface heating is about 1,500 joules at most and that due to cold air advection is 1,500 joules or more. The co-operation of both agencies is most effective at the time of maximum heating energy ; therefore the present result does not contradict the statistical result of maximum occurrence of heat thunderstorms at about 14h. It must be noted here that in the above discussion frontal or cyclonic thunderstorm is excluded. Part I]—SomE PROPERTIES OF CUMULO-NIMBUS The following conclusions are drawn on the properties of thermic cumulo-nimbus from the data of dense network of temporary stations equipped with self-recording instruments (about thirty stations within the area of 100 km. square), which were specially distributed to investigate the minute structure of thunderstorms :— (1) Growth and Decay.—The development of cumulo-nimbus is well explained by moist-labile energy alone from energetical point of view. The cold front accompanying the cloud has only secondary meaning for its development (see (3) ). The amalgamation of cumulo-nimbus masses and the rejuvenation by amalgamation are also explained from the above point of view. _ The moist-labile energy is rapidly consumed, so the cumulo-nimbus generally decays rapidly in energetically isolated environment. The air mass in old cumulo-nimbus is cold and stable, and of entirely different thermodynamical properties from the same cloud in developing stage, which shows the prevalence of radiational cooling. (2) Movement.—The motion of developing cumulo-nimbus is governed by the law of amalgamation ; in other words, the cumulo-nimbus moves towards the region of more labile energy. The rejuvenation of cloud mass by amalgamation may be considered as the natural consequence ‘of the above principle, while the old cumulo-nimbus is drifted by the upper current of 2-3 km. level. (3) Cold Front.—TYhe cold front is formed within the cloud mass, as the result of decending cold air (this front is local and must be distin- guished from that in synoptic weather chart). The front generally moves faster than the cloud mass and runs outside the cloud, then it soon disappears. Sometimes front and cloud show different direction of motion. This is because they obey the different laws of motion. The above facts show that the cold front has no primary effect energetically upon the development of cumulo-nimbus. With the separation of front from cloud, the cloud decays, but, in developing cloud mass a new front is generated after the old front has gone away. INVESTIGATION ON FOGS By U. Naxaya, Hokkaido University Tuis report contains the results obtained by investigation on fogs occurring along the Pacific coasts of Hokkaido in the summers of 1944 and 1945. In the first year the investigation of the property of fog, the meteorological investigation on fog, and the preliminary investi- gation on the artificial dissipation of fog were mainly carried out by 80 about thirty scientists at Nemuro, in the eastern,end of Hokkaido. In these investigations balloon observation in fog and photographing of fog advection by means of slow-speed cine-camera were especially the effective means of investigation. In the second year, the experiment on “‘ fog dissipation car,”’ as a concrete method of the artificial dissipation of fog, was carried out at Tomakomai, in the southern coast of Hokkaido. Further, parallel with this experiment, preliminary tests on the method of measuring fog and on the artificial dissipation of fog were carried out at Kirigamine (1,925m.), Nagano Prefecture and Nisekoan‘nupuri (1,300 m.), Hokkaido. The results of these investigations are summarized as follows :— Part I—INVESTIGATIONS ON THE METHOD OF MEASUREMENTS OF FoG 1. H. Oguchi: Method of Measurement of the Dimension and Number of Fog Particles Detailed investigations and discussions were carried out on the apparatus and its error measuring the dimension and number of fog particles by means of microscopic photographing of fog particles captured on oil membrane made on glass plate. 2. J. Sugaya: Correction of Distribution Curve “a Diameters of Fog Particles by Means of the Rate of Capture Noticing the difference of the rate of capture due to the dimension of fog particles in case of capturing them on glass plate, the method to correct the distribution curve of diameters of fog particles was discussed. 3. M. Hanashima: Measurement of Total Amounts of Waters Contained im the Atmosphere A special apparatus was devised in order to capture, simply and with high accuracy even in open air, the total amounts of waters contained in the air of 20 litres passed through a small glass tube filled with mixture of glass cotton and phosphorous pentoxide. 4. K. Fukutom, H. Kusunoke, and C. Tabata: Measurement of the Amount of Fog Waters by Means of Meshes of Net An apparatus was devised in order to measure the amount of fog waters by capturing fog particles in the air with some gauzes or metal nets laid upon another. By means of this apparatus the dimension of the most frequent radius of fog particles can be known besides the amounts of fog waters. 5. K. Fukutomi and Y. Matsumura: Rate of Capture of Fog Particles by Metal Net The experiments show how fog particles are captured in case of the passing of fog through metal nets. Particles are captured only when their centres hit the wires of metal nets. 6. K. Fukutomi and C. Tabata: Tiral Manufactures of Self-recorder of Amount of Fog Waters The continuous recording of the amounts of fog waters was made with pluviograph by leading fog particles captured by metal nets to it, and at the same time the wind velocity was self-recorded. By using both records the fluctuation of the amounts of fog waters in unit volume air was studied. 81 7. N. Inoue, D. Kuroiwa, and Y. Takeuchi: Trial Manufacture of Electric Visibility Meter—(I) Summer Fog The trial manufacture of an apparatus was made, which is able to measure fog density through night and day by means of light source modulated adequately to photocell receiver. By using the apparatus the relation between fog density and visibility in summer fog and the fine fluctuation of density were studied. 8. N. Inoue, H. Nakayama, and D. Kuroiwa: Trial Manufacture of Electric Visibility Meter—(II) Winter Fog By improving the electric visibility meter described previously in item 7 visibility in winter fog and snowfall and the relation between the discernible distance of light source and fog density were studied. 9. N. Nakayama: On Method of Use of Wigand’s Visibihty Meter As the results of actual observation using Wigand’s visibility meter . it was clarified-that error of 20-30 per cent. was caused by instrumental correction and personal error. However, a method was devised which reduces the error by means of measuring two slightly different distances and putting simultaneously three ground glasses with ditterent density into the same visual field. Part II—SrupDIEsS oF PHYSICAL*PROPERTIES OF FOG 10. H. Oguchi: Measurement of the Radius of Fog Particles at Nemuro and at the Top of Mount Niseko According to the method of measurement mentioned in the item 1 above, diameters were measured for about 150,000 fog particles. These measurements were made in the surface level as well as in a balloon, to investigate the variation of diameter with height. The results thus obtained are as follows: (1) in the case of sea fogs at Nemuro the maximum frequency of diameter distribution was found in the range of 10 to 20, where the size of each particle was not uniform in general but mixed with more larger particles and fine rain-drops towards the lower level ; (2) in the levels near the surface, fogs of dissipation type were frequent, with particles of smaller diameter ; (3) cloud-particles at the top of the Mount Niseko were rather small and uniform in diameter ; (4) it was found that the relation between visibility and diameter of fog-particle can be suitably represented by the Trabert’s formula. ll. J. Sugaya: On the Relation Between the Nature of Fog and the Diameter Ristribution of Fog-particles As the results of observations the author identified two kinds of fogs—viz., dry and wet—the difference of which is to be attributed mainly to the rate of capture of fog-particles. In other words, the dryness of a fog becomes greater with increase of the wind speed and decrease of the size of fog-particle. On the basis of this opinion, the critical condition between dry and wet fog was studied. 82 12. M. Hanashima : Measurement of the Total and Liquid Water Content of Fog By the method mentioned in the item 3 above the total water content in fog was measured, and, combining with the humidity values obtained from the concurrent observation by means of aspiration psychrometer, the liquid water content of fog was calculated. As the results of this it ‘was found that the liquid water content of fog is 0-7 gram, on an average, and utmost about 1-0 gram in | cubic meter. These measurements were made on the ground as well as on a balloon. 13. C. Magono: Measurement of Humidity in Fog by Means of the Aspiration Psvchrometer As the results of humidity observation in fog by means of the aspiration - psychrometer with a simple fog filter it was ascertained that in most’ cases the mean humidity in the fog is less than 100 per cent. 14. N. Inoue and H. Nakayama: Fog and Snow-proof Wind Channel and and Electric Psvchrometer Using the eddy current and the Cottrell’s dust-collecting methods, the authors constructed a wind-channel, free from snow and fog, by means of which precise measurements of humidity were made. Also they devised a psychrometer utilizing the surface resistance of some organic substance against the leakage current to investigate the microscopic variation cf humidity in the fog. 15. H. Ogucht : Observations of the Condensation and Evaporation of Fog Particles On fine days just after rain the author observed how the water vapour evaporated from the surface of the earth, condenses into very fine fog particles by contact with the cold air mass advected from the ocean and how these fog particles evaporate again. 16. N. Inoue and H. Nakayama: On the Visibility in Fog The errors in the observation of visibility arising from the difference in the size and colour of the visibility plate, personal error in estimating the visibility, and the difference of visibility in the horizontal and vertical direction were investigated. The authors also found that the visual range is at least 150 m. in the sea fog of Nemuro even in its densest case, while it can be frequently about 30 m. in the cloud at the top of the Mountain Niseko. : 17. J. Yoshida and K. Uno: Measurement of the Scattering of Light Due to Natural Fogs The authors measured the intensity of scattered light in the fog at the top of the Mountain Niseko by a simple lux-meter. As the results of this a maximum of the intensity of scattered light was found at the scattering angle of 142° for those fogs, consisting mainly of particles about 10 in diameter, while there is not such a maximum in the case of haze, where the size of particles is fine. 83 18. D. Kurotwa and F. Tadano: A study on the Nucleus of Fog by Means of the Electronic Microscope Depositing fog particles on a collodion membrane, the authors investi- gated the remnants left after the evaporation of fog particles by means of an electronic microscope. After examining thirty cases, kinds of bacilli and the particles of aerosols were found, while the existence of the crystal- line sea salt was quite rare. 19. K. Fukutoms: Measurement of the Liquid Water Content of Fog and of the Amount of Chlorine Contained in the Large Drops of Fog by the Gauze Filtering Method The liquid water content of fog was measured by the method men- tioned in the item 4 above, and a value of about 10 to 100 mg./m? was obtained. Also the amount of chlorine contained in the fog particles large enough to be captured by the gauze filter was measured. As the - results of this it was found that this amount of chlorine is less for those fogs with more liquid content, being 7-4 mg./1 for fogs at Nemuro and 1-8 mg./1 for fogs at the top of the Mountain Niseko. Part IJI—METEOROLOGICAL RESEARCHES ON FOG 20. T. Isobe: Estimation of the Vertical Extent of Fog from the Amount of Insolation Comparing the records of insolation made by the Robitsch pyrhelio- . meter and the vertical extents of fog measured by means of a balloon the author studied the relation between them, and ascertained that the vertical extent of fog in fair weather can be estimated by measuring the amount of insolation. 21. Y. Miyake: Estimation of the Vertical Extent of Fog by Means of - the Solar Ultra-violet Ray The author measured the absorption rate of the solar ultra-violet ray in the fog, and ascertained that the vertical extent of fog in fair weather can be approximately estimated by measuring ultra-violet radiation at the ground. 22. U. Nakaya and H. Nakahara: Vertical Distribution of Illumination in Fog Authors investigated the vertical distribution of illumination in fog by means of a balloon equipped with a lux-meter, and found that the illumination increases almost linearly as we go higher up in the sky. By studying the relation between the rate of such increase of illumination and the nature of the fog it was ascertained that the vertical extent of fog can be estimated by measuring the illumination on the ground. 23. U. Nakaya and K. Tsuneizumi: Relation Between Temperature Inversion and Fog Authors made observation of the vertical distribution of the air temperature in fog by means of a balloon almost every day in July and August, 1944. In most cases measurements could reach several hundred meters above the top of the fog, and details of the relations between fog and temperature inversion were revealed. . 84 24. J. Sugaya: Study of the Advection of Fog by Observations on a High Mountain The author made observations on the summit of Mountain Shari (1,650 meters in height), to the extent of 60 to 90 km. from the summit, of the speed and course of the advection of the sea fog, its relation to the wind direction, and the dissipation of fog, as well as the formation and dissipation of mountain fog. 25. U. Nakaya and K. Yoshino: Study of the Advection of Fog by Means of Slow Speed Cinecameras Authors filmed the advection and dissipation of fog by slow-speed cameras installed (1) on Mount Shari, (2) on a balloon flown above the City of Nemuro, and (3) in the seashore of Katsuragi. By these means the aspects of the fog preceding a front, the dissipation of fog, the wave motion of a fog layer, the vortex motion in the uppermost layer of dissipating fog, and the dissipation near the ground were made clear. 26. U. Nakaya, K. Takahashi, and H. Fuchi: Dissipation of Sea-fog as 1t Moves Landward In order to make clear how the sea fog is gradually dissipating being warmed at the ground as it moves landward, we made simultaneous observations at ten points within the range of three kilometers, of the variation of air and earth temperatures, humidity, fog particles, salinity, visibility, &c. According to these observations it may be concluded that the fog is practically dissipated when the air temperature rises about 3:5° c. Part IV.—RESEARCHES ON ARTIFICIAL DISSIPATION 27. K. Takahashi : Dissipation of Fog by Turbulence The author discussed the possibility of artificial dissipation of fog by causing the upper air of high potential temperature to fall to the ground in turbulence, utilizing the temperature inversion which accompanies the fog. 28. K. Takahashi: Removal of Fog by Means of an Obstacle Since fog becomes thin on the lee side of a wood, the author made calculations to ascertain the size of this “‘ shade of the fog’ according to that of the wood and the speed of the wind. 29. K. Takahashi: Dissipation of Fog by Heating The author experimented on the dissipation of fog by forming a hot spot on the ground, and, on the basis of the results obtained he calculated the minimum increase of the temperature needed for dissipating the fog, the process of the diffusion of heat, the loss of heat by radiation or turbulence, &c., and discussed the practicability of dissipating a large mass of fog. 30, Ile Yoshida: Measurement of Evaporation of Fog Particles Taking up the stationary state where fog particles from outside are disappearing, the velocity of evaporation of fog particles was observed. 85 31. T. Miyake: Miscellaneous Experiment Concerning the Artificial Dissvpation of Fog The preliminary experiments on the method of artificial dissipation of fog such as by means of an absorbent, a wire-netting, heating and watering, &c., were performed to investigate to what extent these methods were effective. : 32. J. Yoshida, T. Takano, and D. Kurowa: Preliminary Investigation on the Thermal and Electrical Dissipation of Fog A fundamental experiment was performed to find out the amount of heat necessary for the dissipation of fog by electric heating and by hot air produced by combustion. Further, on the basis of the principle of Cottrell’s dust-absorbing method, a method of catching fog particles was tested and the electric power needed for the dissipation was calculated. 33. Y. Takahashi: Study on the Turbulence Relating to the Artificial Dissipation of Fog In case of artificial dissipation of fog in open spaces such as air fields, the dissipation efficiency decreases owing to the mixing of air current from another place by turbulence. To know the extent of the decrease in efficiency the vorticity in fog was measured by means of hot wire anemometer and resistence thermometer, and on the basis of this measure- ment the dimensions and distribution of dissipating sources were discussed. Further, as the result of the experimental measurement of eddy diffusivity in fog by streaming the cooled air into fog, it was found that an air current of — 5°c. was the most stable. 34. J. Sugaya: Device of “ Foe Dissipation Car’ and its Calculation One é) 5 To dissipate fog at an airfield, the method of distribution of many movable heat sources was adopted and the equipment of a motor-car blowing out hot air produced by the combustion of heavy oil—that is, “ Fog dissipation car ’’— was discussed. 35. Y. Takahashi and |. Sugaya: Trial Manufacture of “ Foe Dissipation G »”) S) a 2 =) ‘ar According to the condition described perviously in the item 34, a “fog dissipation car ’’ was manufactured for trial whose main structure is composed of a combustion cylinder of heavy-oil, a blower blowing out the mixture of hot air and open air, and its motive power equipment.. The trial car has the power as follows: consumption amount of heavy oil, 60 litres per hour. amount of air blowing, 3.7 m*/sec. temperature Ow Ino aie, TO" C. 36. U. Nakaya and J. Yoshida: Experiment on the Dissipation of Fog by Means of “ Fog Dissipation Car ” The experiment on the dissipation of fog was performed at the coast of Tomakomai by means of the “fog dissipation car’’ discussed previously. The range to be dissipated by the trial car,amounted to 20 m. long, 5 m. wide, und 4 m. high. Further, it was shown that Takahashi’s calculation of eddy diffusion described previously in the item 33 nearly held true. 86 ON THE SECONDARY UNDULATIONS OF TIDES CAUSED BY THE CYCLONIC STORM ON APRIL 1-5, 1936 By M. Nakano, Central Meteorological Observatory, Japan | Abstract] On the occasion of the cyclonic storm which swept along our Pacific coast from-Ist to 5th of April, 1936, conspicuous secondary undulations appeared on the mareograms of tidal stations in various parts of this country. In the present paper is reported the result of investigation of periods, amplitudes as well as the time of occurrence of these conspicuous undulations, and some discussions are made on their relations with meteorological conditions. Figure 1 shows the positions of the tidal stations and the track of the centre of the cyclone, where the points marked with A, x, @, and O show the positions of the cyclonic centre at Oh., 6h., 12h.. and 18h. respectively, and the numerals affixed beside the points give the corresponding atmospheric pressure (in mm. Hg) at the centre. 1.NAHA 2 ABURATU 3.S1IMIDU 4 KATUURA 5. MAISAKA ©. MERA 7. TYQSI 8. AYUKAWA 9. HATINOHE EMG, I, On examining the mareograms at each station it was found that conspicuous undulations of longer periods, ranging from 5m—6m to 30m (proper oscillations of bays), generally began six to twelve hours before the arrival of the centre of the cyclone, whereas conspicuous undulations 87 of shorter periods, ranging from 1m to 2m—3m, generally began somewhat later. This relation is illustrated by Fig. 2, where the time, T, is taken as abscissa, and the distance, A, of the respective stations along the path of the cyclone as ordinates, the origin of A corresponding to the position of the cyclonic centre at 6h. a.m., Ist April. The thick full line represents the course of the centre of the cyclone or, in other words, the relation between the time T and the distance A at the time when the centre of the cyclone attained the point nearest 34000 “Ty ost Mera Marsaka | Aatuura 1500} Suna 1000 to the respective station. As seen from this curve, the travelling velocity of the cyclone was at first small, at the middle stage somewhat large, and later small again. From Aburatu to Hatinohe, however, this travelling velocity is nearly constant and approximates 67 km. per hour. The time points marked with | and | correspond to the beginning and the end respectively of the conspicuous undulations of longer periods (proper oscillations of bays), and the points marked with aN | and , to the beginning and the end respectively of the conspicuous Y ndulations of shorter periods (very long swells). Moreover the marks | G | represent the time of maximum amplitude of the undulations | . . of longer and shorter periods respectively. and 88 Now in order to know the relation between these secondary undulations and the meteorological conditions, the course of different isobars during the course of the cyclone was traced by referring to the ‘Daily Weather Charts’’ and the “ Monthly Reports” published from the Central Meteorological Observatory. The time of arrival and departure of the isobars of 760mm., 755mm., 750mm., 745 mm., 740 mm., and 735 mm. for each station was estimated and was drawn in curves, which are shown in full lines, broken lines, chain-lines, &c., respectively in Fig. 2. - ; From this figure we can recognize that the beginning of the con- spicuous undulations of longer periods, peculiar to each station, coincides nearly with the arrival of 755 mm. isobar. cm O0.06mm I heen 0.05 0.04 0-03 0.02 0.0/ 0.03 hen Scale 4o.02 Figure 3 shows the relation between the range of the secondary undulations and various meteorological elements for some stations. The thick full line (===) shows the range (double amplitude) A (in cm.) of the secondary undulations of longer periods (proper oscillations of bays), the thin full line ( ) the range (double amplitude) B (in cm.) of the secondary undulations of shorter periods (very long swells), the thick broken lines (== == ===<—==<=) the velocity of wind W (in m./sec.) at each station, the chain-line (—- -—--—--) the magnitude of the rate of change of the atmospheric pressure P, the chain-line (—-—--—-—-) the pressure gradient G between the centre of the cyclone and each dG dt tidalystation, and the dotted line (=~ 92") ) the magnitude | of the rate of change of the pressure gradient G. In the following we shall summarize the results obtained from the present investigation :— (1) For stations situated along the Pacific coast of Honsyu, Sikoku, and Kyusyu conspicuous undulations of longer periods (proper oscillations of bays) began six to twelve hours before the time of nearest approach of the cyclonic centre to respective stations, and conspicuous undulations of shorter periods (very long swells or waves of one to three minutes periods) generally began somewhat later. (2) The conspicuous undulations of longer periods peculiar to the stations began about the time of arrival of the 755 mm. isobar at the respective station. (3) The conspicuous secondary undulations snl question seem to have no close relation with the velocity of wind, pressure gradient, or the rate of variation of atmospheric pressure in the vicinity of the tidal station. (4) It seems that the present conspicuous undulations were not produced by the passage of lines of discontinuity and cold fronts or by local showers. Besides, it seems difficult to consider that the microbarographic oscillations in the vicinity of the tidal stations became the prime cause of the undulations. (5) The secondary undulations in question seem to have some apparent relation with the time variation of the atmospheric pressure gradient—the amplitude of the undulations is large when the rate of change of the pressure gradient is large. (6) It seems likely that the present conspicuous undulations were not produced directly by the meteorological changes in the immediate vicinity of the tidal stations, but chiefly by the waves which were produced in some region near the centre of the cyclone, perhaps by some microbarographic change, and propagated toward the tidal stations. (7) As is naturally expected, the amplitude of the present secondary undulations has a close relation with the distance of the cyclonic centre from the tidal station. This relation is closer in the case of the undulations of shorter periods than those of longer periods. (8) There is a tendency for the secondary undulation to be large when the depression of the cyclonic centre is low. A detailed discussion will appear in a publication of the Central Meteorological Observatory in the near future. 90 AY SIDAMIDISIOUCAUE SANUND NC Ole! (CILIRIVAUN, UPPED PMU Re evaNCA OURS: RELATED TO TRADE-WIND RAINFALL IN HAWAII By W. A. Morpy and L. B. LEopoip, Pineapple Research Institute of Hawail [A bstract| A statistical study is made of daily Honolulu radio-sonde data and daily rainfall parameters for days classified as trade-wind days. Variations in the factors of wind velocity, temperature, pressure, humidity, and,stability are tested against variations in the daily average of ten high-rainfall stations and ten low-rainfall stations on Oahu. The method is to compute the variance between the rainfall frequency distributions for each of two or three categories of values of temperature, wind velocity, and so on, testing for significance by using the Fisher variance ratio. The factors expected to correlate best with the amounts of oro- graphic rainfall on trade-wind days, such as wind speed and direction, moisture and stability in the layers below the subsidence inversion, do not show as high value of F as the factors of temperature and pressure at very high levels. Both temperature and pressure on these days show increasing correlation in the higher layers with rainfall. SYMPOSIUM ON CLIMATOLOGY OF THE PACIFIC. REGION PE VENA Ne Ye OKe IVAUNE AEs OVikoe iri “CE NG@RAIL PACIEIC By C. J. SEELYE, Victoria University College, Wellington, New Zealand (A bstract(*)| _ Rainfall information is conveyed by a series of maps covering the region between 10° N. and 30°S. and 150° E. and 150° W. These show the average annual rainfall and its percentage variability, the month of greatest and of least average rainfall, the frequency of wet months (taken as those with rainfalls exceeding 150 per cent. of average) and of dry months (under 50 per cent.), the last being given on a seasonal as well as on an annual basis. Brief mention is made of surface winds in abnormally dry and wet years, of the persistence of dry months, and of several spells of exceptional rainfalls. Throughout the discussion the equatorial dry zone (with its south-eastern extension) figures prominently, as it has a rainfall regime distinct from the rest of the region. Its fluctuations, especially in the east-west direction, appear to- produce substantial changes in the rainfall experienced in surrounding areas, and the im- portance of the westward flow of unmodified Tm air near the Equator is thus endorsed from the rainfall statistics examined. DISCUSSION In answer to a question by Dr. Priestley, Dr. Seelye said that un- fortunately no data were available to investigate whether ocean currents might possibly have been the cause of some of the abnormal periods mentioned. (1) The full paper is to appear in the New Zealand Journal of Science and Technology. 91 In answer to a question by Mr. Mordy, Dr. Seelye stated that, with few exceptions, all the data could be fitted into the pattern shown by the charts. In answer to a question by Mr. Simpson, Dr. Seelye stated that there were no reliable charts for this period on which to base correlations with the intensity of the zonal circulation, nor was there any information available to make a correlation with the intensity of the equatorial trough. Dr. Gringorten remarked that the fluctuations in the northern and southern wet zones appeared to be simultaneous as judged by aircraft in-flight reports. Mr. Green was able to confirm this from his experience at Nandi. Colonel Moorman stated that the back records from the former Japanese mandated islands have been collected and will shortly be published. In answer to a question by Captain Best, Dr. Seelye stated that the distribution of rainfall at any one station was not normal, some curves exhibiting a high degree of skewness. CHIMAT OLOGY] OFS TEL, Ce Niwa eA Cre By J. GENTILLI, University of Western Australia In the Proceedings of the Fifth Pacific Science Congress, held in Canada in 1933, Professor Gerhard Schott published a short paper on the distribution of rain over the Pacific Ocean (Schott, 1933). It was a brief paper because the author had already published a comprehensive study of annual and seasonal rainfall over this ocean elsewhere. The same author two years later published his’ major work on the Pacific and Indian Oceans (Schott, 1935). In 1938 the Weather Bureau of the U.S. Department of Agriculture published an Atlas of Climatic Charts of the Oceans (U.S.W.B., 1938) which, for the Pacific Ocean, was based on 1,183,235 observations by ships scattered over 729 five-degree squares. These observations provide the most valuable and reliable source of material for the study of climate over the oceans, but, while they include average cloudiness and frequency of rain, they cannot give actual rainfall measurements. It is true that from a combination of -the published maps showing the frequency of passing showers, steady rain, rain in whatever form, nimbus, cumulo-nimbus, stratus and strato-cumulus, cumulus, alto- cumulus and alto-stratus, cirrus with cirro-stratus and cirro-cumulus, it may be possible to estimate the actual amount of rain, but the result would only be a guess. One still has to use island observations in order to analyse the actual quantity of rain. Various meteorological offices have kindly made available some excellent material on which the following notes are based. ~ The significance of the rainfall is affected by the temperature at the time of fall and immediately afterwards, because any amount of rain that falls is subject to evaporation, which is a function of temperature and other factors, but principally temperature. A relatively simple way of estimating precipitation effectiveness has been evolved by Thornthwaite (1931), and it is this precipitation effectiveness that has been taken as a basis for research in this case. 92 NUMBER OF MONTHS WITH PE >10 160 170 180 170 160 150 140 Map 1. Because of the tentative nature of this work it has been deemed desirable to limit it to the central Pacific, an area where islands abound and less interpolation is required. Rainfall records are available for many islands, and temperature records for several of them. Whenever necessary, temperature records have been interpolated after having taken latitude and currents into account. Precipitation effectiveness had hitherto been used in the assessment of climatic regions on the continents where it has usefully been correlated with vegetation regions (Thornthwaite, 1933). In this case, however, it was necessary to depart from the usual practice and to use precipitation effectiveness over the ocean as a basis for further research. It was also decided to rely on frequencies and on seasonal totals rather than on annual totals as was customarily done. The main pattern which emerges from the following analysis is more complex than was earlier anticipated (Schott, 1933). There are the well-known dry tongue, which reaches along the Equator as far west as the Gilbert Islands, and the moist tongue, which reaches from the Solomon Islands to Samoa and farther east. However, the eastward extension of the moist tongue is subject to notable seasonal variations. A new region of high moisture is added in the region of Rapa. The Fijis are definitely drier than the New Hebrides, although the distance between the two groups is small and their latitude is approximately the same. 93 10 NUMBER OF MONTHS Z WITH PE >6 160 170 /80 170 160 150 140 130 Map 2. After allowance had been made for orographical effects on the high islands it was found that the frequency of months with a precipitation effectiveness greater than 10 followed a distinctive pattern, as shown on Map 1. There are no months with this precipitation effectiveness along the dry tongue reaching from Beru (Gilbert Islands) to Christmas — Island, widening towards the east to include.Malden Island. This tongue is narrower than that postulated by Schott (1933) on the basis of rainfall alone. The belt of ocean with one to three months of precipitation effec- tiveness over 10 is concentric to the dry tongue, including Nauru, Tonga- reva (Penrhyn), and Pitcairn. This is approximately the area with less than seven months of precipitation effectiveness over 6, as shown on Map 2. Nauru and Ocean Island, however, have three months over 10 and seven months over 6, compared with Tongareva’s and Pitcairn’s three and nine respectively. There is little seasonal variation within the dry tongue. Malden reaches a precipitation effectiveness of 15-4 for the southern autumn (Map 4), falling to 6-1 in winter (Map 6), to 2-4 in spring (Map 5), and rising again to 6-8 in summer (Map 3). The other islands in the vicinity show similar variations, and it may therefore be assumed that the dry tongue does not change its latitude throughout the vear, but rather shows a greater or smaller advance westwards. 94 160. 170 180 170 160 150 140 Map 3. In view of the fact that the prevailing winds are almost invariably easterlies with a weak southerly component (U.S.W.B., 1938) it may be necessary to seek an explanation of the advance and retreat of the dry tongue in the conditions of the water surface at different times of the year. In winter the southern Pacific is under the control of two great anti- cyclones, one centred about 100° W. and 25°S., the other one about 180° E. and 25°S. (Map 7B). The eastern anticyclone is generally recog- nized (Haurwitz and Austin, 1944), the western one links up with the Australian winter anticyclone and loses its identity. It is the eastern anticyclone that gives rise to the steady easterlies of winter between latitudes 2° and 12°S. These easterlies blow over a water surface which is as cool as 16° and 17° c. near the South American shore, and warms up progressively until it reaches 28° c. at about 177° E. along the Equator (Sverdrup and others, 1942). The air mass finds itself constantly warmer than the underlying surface, and its relative humidity decreases, notwithstanding the continuous intake of more moisture from the ocean surface. In summer the same air mass travels over a water surface which varies in temperature between 21° and 28°c. over the same distance. The rise in temperature is only 7° c., as against 12° c. in winter. The moist tongue reaches from the Solomons to Samoa, but its eastward extension varies with the seasons. It always reaches as far as Pukapuka in the Danger Group, where summer is the wettest season, 95 130 ear Nee eal 73. 32 Map 4. followed by spring and autumn. Winter (Map 6) has the lowest precipita- tion effectiveness, less than one-half of that of summer. This seasonal pattern is quite different from the one shown by the Line Islands, of which Malden was quoted as an example. It resembles the seasonal pattern of the Gilbert Islands, much farther west. It may be advisable to seek a common factor underlying these similar patterns. This factor is provided by the wind pattern (U.S.W.B., 1938). In the southern summer (Map 7A) the outflowing Asiatic monsoon causes a deflection of the north-east trades, which are greatly strengthened and are able to advance beyond the Equator as far as 175° W. and 15°S. in February. The intertropical front runs farther north than was postu- lated by Bergeron and other authors (Miller, 1946 ; Haurwitz and Austin, 1944), approximately along the boundary between Papua and the Terri- tory of New Guinea, south of the Solomons, north of the New Hebrides to a point between the New Hebrides and Fiji, then north of Fiji to Samoa and Pukapuka. It is important to note that the western anticyclone of the South Pacific is well developed in summer, and its north-westward winds blow steadily as far as Fiji, which is thus kept relatively dry. These winds do not quite cover the New Hebrides, and thus allow the air masses from the Northern Hemisphere to sweep over these islands at times. In other words, the intertropical front is well stabilized north of Fiji, and moves slightly north and south over the New Hebrides, although its average position in February is just to the north of these islands. 96 0 TO, 20 SOUTHERN, SPRING 5 9, Sf “ ws TES at | m4 24 | | i} c LA eit 160 170 189 170 160 : ko 149 Map 5. ® Conditions show little change in March. By April the intertropical front runs over northern New Guinea, along the Solomons, to the north of the New Hebrides and Fiji. Here again the north-east trades may advance ,well over the New Hebrides, while Fiji is well under the influence of the south-east trades. High precipitation effectiveness is therefore found in autumn over the New Hebrides, and even as far as New Caledonia, whereas precipitation effectiveness is much lower in Fiji (Map 4). _ In winter there is a tongue of high precipitation effectiveness running along the northern side of the Solomons and extending to Santa Cruz (Map 6). The precipitation effectiveness decreases slightly farther east, but the tongue is still clearly recognizable as far east as Manihiki and Tongareva (Penrhyn). The standard works on the subject do not mention the existence of any front, and convection due to heating is out of the question at this time of the year. The explanation here put forward is the formation of shearing fronts due to the convergence of air masses not from opposite directions as usually happens in normal fronts, but from directions forming an angle of 15 or 20 degrees only. These shearing fronts could only result in plentiful precipitation if the winds forming them were steady and strong and if the warmer air mass were quite unstable. They are provisionally shown with the stationary-front symbol on Maps 7A and 7B. 9% 4-—-Pac. Congress b—__+- SURREDM PILIREE ee aaa 160 770 0 770 160 Map 6. The winter distribution of pressure systems over the southern Pacific has already been mentioned above. The eastern anticyclone sends strong winds which give rise to a shearing front between 135° and 145° W. when they meet the winds from the western anticyclone (Map 7B). The result is the relatively high precipitation effectiveness of the Marquesas in winter, much higher than that of the islands farther north or south (Map 6). Between 145° and 155° W. the winds from both anticyclones proceed in a parallel direction (U.S.W.B., 1938), and the precipitation effectiveness falls. Between 155° W., 12°S., and 150° E., 5° S. a much more effective shearing front develops between the westward flow from the eastern anticyclone, the west-north-westward flow from the westward one, and the strong north-westward flow from the Australian’ winter anticyclone under monsoonal influence (Map 78). It is especially over the Santa Cruz and north of the Solomons that the shearing angle grows to nearly 45 degrees, thus giving rise to a much more effective front than was the case farther east. The trades which arise from the western anticyclone continue to reduce the precipitation effectiveness of Fiji throughout the year. The eastern shearing front which affects the Marquesas in winter disappears in the course of spring (Map 5) because the western anti- cyclone is greatly weakened (U.S.W.B., 1938). A new feature develops at this time farther south, between the Society Island and the Tubuai or Austral Islands, a small anticyclone centred at about 140° W. 35° S. 98 INTERTROPICAL FRONT =m DRY TONGVE & COLD FRONT 2a SHEARIHG FRONT MAP 7. This gives rise to a seasonal front between 138° W., 35° S. and 155° W., 97° S., as is well shown by the map of precipitation effectiveness in spring. The highest ‘precipitation effectiveness known for this zone in spring is found at Rapa (Map 5). In the summer the small central anticyclone weakens and moves farther south (Map 3), so that no records are available except some signs of higher nebulosity (U.S.W.B., 1938). In autumn the area of high pre- cipitation effectiveness reappears with greater intensity, extending farther to the north-west to include the Tubuai or Austral Islands as well as Rapa (Map 4). It is especially in late autumn (May) that pre- cipitation effectiveness is high and it is at this time of the year that winds follow a complicated pattern (U.S.W.B., 1938) which has all the require- ments for frontogenesis from Rapa to Tubuai. In winter (Map 7B) the small central anticyclone tends to disappear — between the two great anticyclones and Rapa finds itself just along the line of frontogenesis (135° W., 35° S. to 147° W., 28° S.) while the nearby islands have the usual incidence of fronts from travelling depressions as are found in these latitudes in winter. However high the winter precipitation effectiveness of Lord Howe Island, Norfolk Island, the Kermadecs, and Pitcairn may be it is not as high as that of Rapa, where actual frontogenesis takes place (Map 6). It is interesting to note that a front in the vicinity of Rapa had been postulated by Bergeron (Miller, 1946) and by Haurwitz and Austin (1944). 99 Summing up, the pattern which emerges from the present analysis is as follows :— (a) A dry tongue along the Equator is due to water temperatures. (b) A moist tongue immediately to the south is due to shearing fronts throughout the year, except in summer and early autumn, when it is due to the intertropical front. (c) Shearing fronts are most noticeable in winter, and especially along the north-eastern edge of the Australian anticyclone. (d) A definite frontogenetical area exists in the vicinity of Rapa. (e) A small anticyclone tends to appear between the two great anti- cyclones of the southern Pacific at some times of the year. REFERENCES Byers, H. R. (1944): General Meteorology. New York. Commonwealth of Australia (1940): Results of Rainfall Observations Made in Papua, &c. Melbourne. Etablissements. Francais de l’Océanie (1940-1945) : Reswmé des observations faites Ci ei eehce Fiji Meteorological Office (1948) : Oviginal records. Suva. Haurwitz, B., and Austin, J. M. (1944): Chmatology. New York. Mirzier, A. A. (1946): Climatology. London. New Zealand Meteorological Office (1943): Climatological Notes, South Pacific Region. Wellington. PETTERSSEN, S. (1940): Weather Analysis and Forecasting. New York. ScHoTt, G. (1933): The Distribution of Rain Over the Pacific Ocean (in Proceedings of the Fifth Pacific Science Congress, III, 1933). Ottawa. (1935): Geographie des Indischen und Stillen Ozeans. Hamburg. SHaw, N., and Austin, Evarne (1942): Manual of Meteorology—Vol. Il: Comparative Meteorology. Cambridge. SVERDRUP, H. U.; Jounson, M. W.; and FLEemine, R. H. (1942): The Oceans. New York. ‘THORNTHWAITE, C. W. (1931): The Climates of North America According to a New Classification. (In Geog. R., X XI, 663.) New York. U.S.W.B. (1938) = U.S. Department of Agriculture, Weather Bureau: Atlas of Climatic Charts of the Oceans. Washington. . DISCUSSION The paper provoked considerable discussion, and many present were not entirely in agreement with some of the views put forward. In this connection Dr. Thomson expressed some doubt as to whether the formula for precipitation effectiveness could be applied in the Tropics. He pointed out that the formula was originally worked out only for a section of the eastern U.S.A. He considered, however, that further work should be done to test the applicability of the formula to other parts of the globe. Mr. Simpson expressed his doubts that the low temperature of the sea-surface water was a cause of the dry zone observed near the Equator, but would rather consider the low temperatures of the surface water as a result of divergence in wind flow. Mr. Rose pointed out that a Thornthwaite classification of climate had been attempted in New Zealand and that the formula for precipi- tation effectiveness seemed to have a broad general validity. Dr. Spilhaus pointed out the great difficulty caused by orographical effects on rainfall of mountainous islands and doubted whether these gave any indication at all of the rainfall over the sea. 100 PED eA AE Le DIS RTD UIhON ENT LES -PACIRIC REGION By TAKESHI SEKIGUCHI, Central Meteorological Observatory, Japan [A bstract] The islands of the Pacific do not show any remarkable relief so that we might expect the development of zonal climatic areas, especially with regard to rainfall. Up to the present the most precise information on the rainfall distribution was that published by G. Schott in 1933 Since then more precise and more numerous climatic data have come to hand from many stations in the Pacific. From these data a new rainfall map of the Pacific Ocean can be drawn (Fig. 2). This paper gives a description of the new rainfall map and attempts the classification of the Pacific into rainfall zones. It is pointed out that the rainfall of some of the Pacific islands shows very great variability, and a map of the annual variation of rainfall is presented (Fig. 1). DISCUSSION It was agreed that the map was more reliable in the neighbourhood of the former Japanese mandated islands, but doubts were expressed as to the appropriateness of the values taken for the rainfall of such places as the Hawatian Islands and the region north-east of the Cook Islands. ST PAUL Js. DUTCH HARBOUR MIDWAY HONOKAA BE TSRSSS 20.0 SSE Wis FANNING SY XS MALDEN APIA (SAMOA) AVARUA RURUTU CHATHAM MACQUARIE 1707 wX \ sé cow *&tt4\ YT < 000 l=’ [uve0() 214190 244 $0 d Dy) Thawaas 102 FLUCTUATIONS AND SECULAK TREND OF NEW ZEALAND RAINFALL By C. J. SEELYE, Victoria University College, New Zealand (A bstract(*)] A list of annual rainfall indices for both North and South Island is given, the index being the average over a selection of stations of their rainfall expressed as a percentage of the 1911-40 mean. Accurate indices were obtained from 1911 to date, and with decreasing reliability back to 1852. In the majority of years the dispersion of rainfall amongst New Zealand. stations has a standard deviation from 14 to 19 per cent. The fluctuations from year to year are resolved into a longer period by smoothing, and the residual gives a shorter period. The coefficient of correlation of the former with sunspot number is 0-47 for the North Island and 0-31 for the South and over an average cycle the rainfall moves closely in phase with the sunspots through ranges of 13 and 4 per cent. in the two islands respectively. For the shorter fluctuation there is an average period of. about three years and average range of 21 and 17 per cent. Both period and amplitude are irregular, and there is little similarity between the two islands except at or immediately after sunspot maximum. Using moving thirty year means from the 1863— 1947 indices average rates of decline of 4 per cent. and 2 per cent. per century for North and South Island are obtained. Recognition of a trend requires more critical examination of the indices before 1890 when isolated records cannot be satisfactorily reduced to standard epoch. Assuming the average trend of the island could be applied in such cases most of these earlier indices should be increased by 1 or 2 per cent. and the revised trends become 6-7 and 3-3 per cent. per century. Further knowledge of the three-year cycle over the Pacific region seems desirable if the irregular variations noted are to contribute to any method of long range “forecasting. DISCUSSION In the discussion Captain Best raised the question of the significance of the correlation coefficients given in this paper. Dr. Seelye replied that the graphical representation in his paper gave one more confidence in the correlation coefficients, and although they were not particularly high he thought that they were of significance. Mr. B. W. Collins offered a very interesting contribution from the point of view of a ground-water geologist. The figures given by Mr. Collins showed that the level of ground-water in Canterbury in recent years tended to confirm the findings of Dr. Seelye. Dr. Berlage asked if a similar study with regard to seasonal variation of rainfall should not be undertaken. Dr. Seelye agreed that such a study would be well worth while. In reply to a question by Mr. Mordy regarding the distribution of the stations used to compute the rainfall indices, Dr. Seelye replied that they were selected in the same way as those of the British Rainfall Organiza- tion, in order to give an adequate coverage of the rainfall of the whole country. (4) The full paper will appear in the New Zealand Journal of Science and Technology. 103 DROUGHTS IN NEW ZEALAND By F. Bonpy, New Zealand Meteorological Service | A bstract(*) | This paper discusses several aspects of the occurrence of absolute and partial droughts in New Zealand. The material is derived from the records of forty-six stations, these being selected to give as good a coverage of the Dominion as possible. Absolute and partial droughts were classified according to their duration and expressed as percentages. Absolute droughts, in excess of six weeks, have been recorded at Nelson, North and Central Otago, and in several other places. In twenty-five of the forty-six stations the majority of the recorded partial droughts lasted into the sixth week, Days lying within each absolute and partial drought were averaged by months and years for each of the stations. These averages when con- verted to percentages of the total number of days in the month or year provide a useful means of comparing the geographical and seasonal distribution. Naturally the areas with low rainfall will in general be those most subject to absolute and partial droughts, as is shown by a comparison of a map giving the distribution of droughts with an annual rainfall map. Differences evident in the North Island may be interpreted in terms of rainfall variability showing a close connection between high rainfall variability and high incidence of drought, and vice versa. From the available figures it is possible to recognize at least three types of seasonal variation. In type “ A,” found in the northern, central, and south-western portions of the North Island and in Nelson, Marl- borough, and the North Canterbury Districts, February is the month with the greatest number of days falling within a drought. At this time maximum anticyclonic conditions are normally present affecting the weather of the North Island and large portions of the South Island. Type “ B,” which is typical for the east of the southern half of the North Island, has its maximum in December and January. Heavy downpours connected with the passage of cyclones of tropical and subtropical origin in late summer and early autumn often break up the droughts. Type “C ” gives a maximum in winter and is encountered in South Canterbury and Central Otago. This area is sheltered from rain-bringing westerlies, Central Otago also from south-easterlies, hence the dry winter. Threaten- ed summer droughts are frequently broken by isolated showers of convectional origin. The longest absolute drought recorded at any of the forty-six stations occurred at East Cape during the summer of 1927-1928 and lasted 64 days. The longest partial drought occurred in the winter of 1939 at Clyde. It lasted 176 days, during which 1-68 in. of rain fell. Droughts which have effected large portions of the country since the turn of the century occurred during the following seasons: summer, 1907—08 ; winter-spring, 1914; summer, 1916-17; summer-autumn, 1919; summer, 1927-28 ; summer, 1928-29 ; summer-autumn, 1950; summer. 1934-35 ; summer, 1938-39 ; summer, 1945-46; and summer, 1946-47. A comparison of the average number of days belonging to partial droughts, computed for eighty years with a corresponding series of sunspot figures, shows a tendency of sunspot maxima to coincide within two years with drought minimum. (‘) The full paper, including tables and figures, has been submitted for publication in the New Zealand Journal of Science and Technology: 104. 410 THE MEAN MONTHLY AIR TRANSPORT INTO THE CONTINENT OF AUSTRALIA, AND ITS SEASONAL VARIATION By H. ARAKAWA, T. SAKITA, S. Fuji, I: FuyrnumA and T. Hosino, Central Meteorological Observatory, Japan THE present paper treated the wind conditions around the continent of Australia on the basis of the pilot charts of the Indian Ocean, regularly issued by the Hydrographic Office of the U.S. Navy Department. The charts contain a great amount of information useful to sailors as well as weather men. This paper is a discussion of the wind conditions on the boundary part of the Continent of Australia, of which the representa- tion of the wind is a point of chief interest. As to the interpretation of the wind roses, the following quotation from the text printed on the charts may give the best account. The wind roses in each 5-degree square show the frequency, the direction, and the average force of the winds that may be expected to prevail within that square. At the request of this office the wind percentages: were concentrated upon eight points . . . The-length of the arrow measured from the centre of the circles gives, by means of the attached scale, the number of times in each 100 observations that the wind may be expected to blow from the given point. The number of the feathers indicates the average force of the wind according to the Beaufort scale. The percentage of calms, light airs, and variable winds is shown by the number within the circle 120. /30 _ /40 150 160 170 There are several different scales known as “ Beaufort ’’ in use. That adopted by the Hydrographic Office and Weather Bureau is known as the “ Scott ’’ scale and differs slightly from the English. To get an immediate perception of the actual average air transport ave calculated the resulting mean velocity, representing the average air 105 transport per second after W. Wereskiold’s method(*). First the length of the arrows for each wind rose has been measured by the percentage scale. (Some few gross errors were, however, detected.) The next stage is to get the forces reduced to velocities. We have used simple averages of the limits of the velocities corresponding to each force, the tables being as follows : : | wl | Force | 5) ee | 5 : | 3 Seoul ee (Beaufort). | 0. | Il, | 2. | 3 | 4. | 5. | 6. | i. | 8. | 9. | 10. Velocity -. | 0-67) 2-46) 4-69) 6-93) 9-16)11-40)13-86 16-54)19-67/23-24127- 04 (m. /sec.) | The graphic tables by W. Wereskiold, which give the mean velocity component in m./sec. in the N.-S. and the E.-W. directions were used quite frequently. The resulting components in the N.-S. and the K.-W. directions were found by simple addition and subtraction; the result is written down by two components (N. and E.) for each wind rose. The magnitude of the mean resultant velocity (V) was calculated by the formula V=/ N?+E? and the direction of the mean resultant velocity (a) was determined by the formula tan a = = so the directions.of N., E., S., and W. are given by 0°, 90°, 180°, and 270° respectively. (1) Geof. Publ., Vol. II, No. 9 (1922). 106 The mean directions and velocities of wind were found and drawn in vectorial form in Figs. 1-4. One resultant wind vector, which has been drawn as an arrow, corresponds to each wind rose. The number attached to each vector indicates the region by the five-degree square, and the magnitude and. direction of resulting velocities has been tabulated in table I according to this number. TABLE | July. October . | January. } April. No | V a W a. Vv a i a. (m./sec.). (m./sec.). (m./sec.). (m./sec.). | - | 1 3°34 256 52 BOT 295 34 119.535} 258 40 m1) Dyes AT 2 1:99 315 39 4-21 244 32 4-27 190 50 Ifo ay!) 236 50 3 1-01 213 10 3°24 242 48 3-06 1912 VO) | E69 257 45 4 2-54 29 15 4-42 | 233 11 LO) 229 50 5-13 264 24 5 3-48 272 18 3-35 265 23 1-80 109 20 5°55 277 0 6 6-95 286 36 3°28 259 49 ILS tess} 262 0 1-93 251 16 7 | 4-93 21899 BOAT Ome) 4-90 181 10 0-29 2M Bo) 8 3-49 267 16 4-09 214 56 | 6-83 162 10 a7 211 40 9 3°48 260 33 7:62 185 30 | 7:90 166 10 2:24 179 14 10 2-35 159 40 6275 LOOM seo, 309 10 6-24 169 53 I] 4-42 144 10 5-45 156 12>) 3253 255 0 6-39 158 14 12 8-91 132 16 6-39 142 42 4-34 269 10 6-12 140 6 13 \ 4-76 139 16 4-4] 36916 289 284 10 1-94 185 52 14 9-18 118 15 4-51 Jil. 20 1-90 360 0 5-15 127 50 15 8-78 TENG: Sz 5-38 122 29 4-03 119 50 5-09 oe) © 16 5-46 115 36 6-44 WLS U7 5:20 90 0 5-15 112 20 17 6-24 113 55 5-84 94 25 og) 105 40 4-56 116 19 18 7:49 123) 17 5:4] Oey ale | so 740) 88 40 6-69 NG) 7 19 6-68 124 12 2-48 50 25 4-21 93 50 7°32 117 42 20 5:45 127 56 0:75 46 5 bof Bd 4-70 128 23 2) 5-28 1388 30 3-54 219) 59) SA |i Tho 153 54 22 6-15 101 20 Bis i | ve Ee etal ea O mat 23 2-89 | 134 35 A ieee a, a Wl Rae 24 216 BANG) a6 | Se ec | Be | ie 25 Bea 20! AOU hi asks ian am eee st Pee | 26 3-49 240 50 | Assuming that the air current is the same throughout the lowest 1 km. layer, thé total amount of mean monthly air transport (per second) into the Continent of Australia was found to be as follows :— —-- January, April. July. October. Total flow into the Continent of Australia | 21-05 x 10° | 10-84 x 10° 8-78 x 10)° | 16-96 x 102 m. */sec. m. °/sec. dla YAEL m. °/sec. Total flow out of the Continent of Australia 4-96 x 10° 9-98 x 10° | 24-84 x 10° | 16-32 x 10° Net air-flow into the Continent of Australia | 16-09 x 10° 0:86 x 10° |—16-06 x 10° 0-64 x 10° Length of the coast of Australia used in 9,777 km. 12.127 km. | 1 computation | 3,382 km. 12,352 km: Under the assumptions described above, the net air-flow into the Continent of Australia in January, April, July, and October is estimated roughly, as 16 x 10° m.*/sec., 0:86 x 10° m.?/sec., —16 x 10° m.?/sec., and 0-64 x 10° m.?/sec. respectively. The net air-flow out of the Continent of Australia in July explains the predominant descending 108 motion over this continent and the resulting fair weather. Further assuming that the absolute humidity of the air flowing into the continent is about 10 g./m.*, the total amounts of water vapour flowing into this continent are— For January .. hie IG X< IOS, / See. For April ¥ oa) OPES SCO! © wise. For July i - wo For October .. on » ORE S< HOSS eo Sae, respectively. If these amounts of water vapour are wholly condensed by the converging-ascending motion, the resulting average precipitations over the Continent of Australia are estimated as— For January ~ = 37 s 5 9) OO TaN For March ie ‘ so GAA, For July ah % + For October Ae . oe) Zieauany, Naturally, the air-transport flowing into the continent must be compen- sated by the diverging air in the upper layer over the continent. CLIMATIC CHANGE OBSERVED IN JAPAN By Takeo YAMAMOTO, Ube Technical College, Japan 1. INTRODUCTION A. WAGNER(*) showed the fact that the climate has changed with a tendency for the annual variations of air temperatures to decrease in Europe in the past ever since instrumental observations were established. As for Japan, H. Arakawa(’, *) pointed out that, barring seeming changes due to the expansion of cities like Tokyo, Osaka, and Kyoto, the mean annual temperature of any place has been practically constant during the past fifty years, thereby concluding that the secular change of the Japanese climate is too imperceptible to be affirmed. This is one fact to be noted, but as climatic change ought to be defined in due consideration of variation in the character of all factors bearing on the annual weather conditions, the annualranges of air temperatures observed in Japan, for example, also requests careful study in this connection, and the problems concerning the climate change in Japan are to be reinvestigated. 2. SECULAR CHANGE OF ANNUAL RANGES OF AIR TEMPERATURE OBSERVED IN JAPAN With ten-year means of the data I found that the air temperatures in winter season (December, January, and February) are lowering and in summer (June, July, and August) are rising up to the presént indicating extreme parts around 1900.A.D. in almost all the regions in Japan as shown in “Fig. 1, in which the curves of secular change of winter and summer temperatures are made by smoothing ten-year means by the a + 2b.-+ ¢. 4 I have calculated the annual range of air temperature in each year taking first term of sine series expanded from yearly change of air temperature by the method of harmonic analysis. As will be seen in formula 109 -0.4 | ——agoshil ; ~~~ fu shihi 0.3 -0-4 18990 KOO 310 1920 /930 1440 Fic. 1.—General aspect of secular variation of air temperatures in Japan. Jannval means oF as Lemp. ¥ PESOS K agosh ima. Sn Mae = ee ee ee eee 189° (foo0 190 1920 1930 1940 Fic. 2.—Secular changes of annual ranges of air temperature compared with those of annual means of air temperatures at Kagoshima. 110 air Cermperature Jajnuany Bo) +04 +05 7888 7396 (908 (9/8 1928 1938 Fic. 3.—Secular changes of air tempera- ture and precipitation in January at Hushiki. the following Table I, there exists in the change of ten-year means of annual ranges of air temperature marked and widespread trends such as are never found in the annual mean of air temperatures (see Fig. 2). In order to explain the character of the above-mentioned climatic trends of Japan more minutely I like to begin with the observation data gained at Hushiki, a meteorological observation station along the Japan Sea. Figure 3 shows the curves of secular variations of air temperature and precipitations in January at Hushiki, obtained by smoothing the @ = Gp) SE 6 1 Fig. 4 shows the curves of the secular variation of air temperatures as well as precipitations in the summer season (from June to August) at Hushiki, obtained by the same method as in the case of midwinter. Comparing them one will find to one’s surprise the quite similar form between the curves of winter and summer, the co-ordinate of midwinter . temperatures and precipitations being ‘taken positive respectively downwards and upwards, vice versa in the case of summer. The summer temperatures at Hushiki rise in the same process in which the midwinter temperatures fall, and as for the precipitations the same thing can be _ observed. ; successive five-year mean according to the formula , while 1B +0.4 + 0.3 +0.2 +0.) ny d ular ch ange of i Waceik of the ‘aia High during SUMmer -0-2 Bor} ca Sie! int™m +100 1293 1903 1915 1923 1933 1943 Fic. 4.—Secular variation of air temperature and_ precipitation during summer of Hushiki. The striking contrast between the features of secular variation of summer and winter climate especially of air temperatures as above mentioned is to be found not only at Hushiki, but also in almost all the parts of Japan. I have calculated the correlation coefficient between ten year means of summer temperatures (June, July, and August) and that of winter (December, January, and February) at twenty places(*) scattered on Kyushu, Shikoku, and the Japan Proper, as shown in Fig. 5 the value of the coefficient being 7 = — (0-61 + 0-06). Generally speaking, the climate of Japan has changed, increasing the annual range of air temperatures—that is to say, growing gradually colder in winter and gradually warmer in summer during the past fifty years. (1) Kagoshima, Hukuoka, Hiroshima, Sakai, Kochi, Wakayama, Hikone, Tu, Hamamatsu, Nagano, Choshi, Utsunomiya, Hukushima, Yamagata, Miyako, Mukui, Tsuruga, Hushiki, Niigata, Akita. : 112 +a6s Fic. 5.—Correlation of ten year means of summer temperatures with those of winter temperatures at various places in Japan. 3. THE METEOROLOGICAL MECHANISM OF THE SECULAR TRENDS OF JAPANESE CLIMATE It is a well-known fact that the climate of Japan in winter is chiefly influenced by the Siberian High, and that in summer it is influenced by the North Pacific High. As for the case of winter, the cold air current originating from the Siberian High prevails over Japan Islands, bringing much precipitation in the districts along the Japan Sea by passing over the sea warmer than the continent. The secular trends of air tempera- tures and precipitation in midwinter observed at Hushiki, as shown in Fig. 3, are ascribable to the rise and fall of the intensity of the geostrophic ; en i ) : wind, which is proportional to es —1.e., the pressure difference of two points fixed on the normal line of mean isobar-curves. I have taken up the pressure difference between Nikolsk (long. 131° 57’ E.; lat. 43° 47’) and Asahigawa (long. 143° 22’ E.; lat. 43° 47’) in January, which correlates very clearly in each individual year with the data of air temperatures in January at various places in Japan as shown in Fig. 6. On the other hand, the action centres governing the weather of the Far East in summer exists in the high pressure area over the North Pacific Ocean, the so called North Pacific High. The temperature in 113 ¢ Oo 6 Migate, F2067 £009 Harsdi ki Ps @ Y°OTTLOOT ° Wokayama >» 9 8 F-278t007 Bem .. O a ; 234 5 6 T 8 Sim Fic. 6.—Correlation of air tem- perature in January with pressure differential between Nikolsk and Asahigawa. summer rises due to the air current from the.low latitude zone revolving with the North Pacific High on its right. Using the ledgers of weather charts published at Kobe Marine Observatory, I have investigated the change of the five-year means of pressures of the area within the rectangle, bounded by longitude 180° E. to 130° W. and latitude 25° N. to 50° N. for the period from 1911 to 1935. As shown in Fig. 7, the curve of the secular change of intensity of pressures within the rectangular area, which is obtained by averaging the data of each. section divided by every longitude 5° and latitude 5°, is in good harmony with that of summer air temperatures as well as precipitations at Hushiki. The curves of secular trend of the amount of precipitation observed” in central part of the Japan Proper are shown in Fig. 7; with the increase of the intensity of the North Pacific High, the high-pressure zone extends over the Japan Proper and diminishes the amount of precipitation in the said district, by pushing the isobar-curves northwards, along which depressions tend to proceed(4). The above-described various facts seem to lead us to the conclusion that the Siberian High in winter as well as the Pacific High in summer have been heightened, since around 19004.D., in other words, the 114 Sect chan es ~-0,2 ot gant B aa High ¢€ Necgat Nagano { Meatsumota 7 -497™ ee ee | ee | Cree | (893 1903 1913 1913 1933 1943 Fic. 7.—The secular change of the amount of precipitation during summer season in the central part of Japan proper j intensities of winter and summer monsoons in the Far East have been increasing in the past fifty years, and that is the cause which has widened the annual range of air temperatures in the most part of Japan as I showed in the preceding paragraph. 4. THE SuN’s ACTIVITY AS A POSSIBLE FACTOR ON THE SECULAR CHANGE OF CLIMATE As above stated, it can fairly be concluded that the changes observ- able in the climate of Japan are due to the fact that the monsoons, both in winter and summer, in the Far East are growing active. A. Wagner(5) and others(6) have also referred to the increasing activity of the general circulations ‘of atmosphere in their attempts to explain the trend of climatic change in Europe. Collating all the information available, it is conceivable that the general current of atmosphere over the northern hemisphere has gained in intensity. 115 / a r) +/0 i Say fo) adsl eae ; = ° Ds Misia V8 + SFh ies : 440.5 ; 3 ri w ~ ‘ L S 8 eg Ay ~> Bi Si er 2 ' 4 ema S 5 ‘ | el -O.5 =H wv ' anmue! ra x ie of air temp, oan ssccee Sunspot, ‘S) avm bey s—, -/0O 5 —f'0 [eeerra yawn eeweru area Guard Womw) RWnUD ive Wee ne Keron ee ee CeO TTS | 6670 (889 1890 1900470 1920-1930 1949 Fic. 8.—Comparison of the year running means of the annual ranges of air temperature at Hakodate with those of sunspot numbers H. H. Clayton(7) indicated that during periods of high sunspot activity the pressure is lower in low latitudes and higher in high latitudes, and during periods of low activity higher and lower respectively. I. I. Schell(8) has recently verified the above-mentioned indications. It may not be incorrect to conclude that the global pressure distribution —that is to say, the intensities of general circulations on the earth— is actually influenced by the sun’s activity in itself. As shown in Fig. 8, comparison between the eleven-year running mean of the annual ranges of air temperatures at Hakodate, which has the oldest history of meteorological observation in Japan, and the eleven- year running mean of sunspot numbers proves a surprising accord between terrestrial phenomena and astronomical factors. In my opinion, as the motive power for secular climatic change solar activity in itself ought to be regarded as constituting the most _ possible factor, if not the sole. But it is a mistake, as has often been attempted, to link solar activity directly to climatic factors at all places, for, as the intensity of the general circulation of atmosphere on the earth rises or falls according to change in the solar activity and as the climatic factors at various places change under the influence of the general circulation of atmosphere, for instance, it happens that the amount of precipitation increases in some places and decreases in other places. As will be seen from the following Table II, the secular change in the amount of precipitation in summer at Hushiki and Gifu, in central Japan, and those at Nemuro, in Hokkaido, are going on inversely. 116 5. REMARKS I have presented my conclusion with the reference to the secular change of climate in Japan, attempting to make clear the controlling factors of this change. The problem may be very important related with ‘‘ Weather Forecast.” I wish to express my deep thanks to Dr. K. Wadati, Director of Central Meteorological Observatory of Japan, -who extended me a great deal of kind help. REFERENCES (1) A. WacGNER: Untersuchung der sakularen Anderung der Jahresschwankung der Temperattire in Europe. Gevrl. Beity. Z. Geophys, 20, 134, 1928. (2) H. Arakawa: Is the Climate of Japan Changing? Journal of the Meteoro- logical Society of Japan, 14, 425, 1936. Increasing Temperature in Large Developing Cities. Gerl. Beitr. Z. Geophys, 50, 3, 1937. (4) K. TaxanasHt: On Various Methods for Forecasting Courses and Speeds of Typhoons. Journal of the Meteorological Society of Japan, 17, 1939. (5) A. WaGneR: Untersuchung der Schwankungen der allgemeinen Zirkulation. Geogr. Annalar., 1929, s. 33. (6) R. ScHERHAG: Die Zunahme atmospharischen Zirkulation in den letzten 25 Jahren. Ann. d. Hydy., 1936, -s. 96. (7) Crayton, H. H.: Solar Activity and Long Period Weather Changes. Smith. Misc. Coli. V, 78, 1926. (8) I. I. ScHrrt: The Sun’s Spottedness as a Possible Factor in Terrestrial Pressures. The Bull. of A.M.S., Vol. 24, March, 1943, No. 3. 3) TABLE I—CHANGE OF ANNUAL RANGES OF AIR TEMPERATURES : (Deviation from the mean in © Cc.) Place. | Kagoshima(1). | -Hushiki(2). | Miyako(3). Hakodate(4). Period— 1886-1895 ..- ae 0-04 O06 —0-08 | —0-20 1896-1905 .. eS —1-30 | —0-90 | —]-12 —1-12 1906-1915 .. Set —0-76 | —0-62 | —(Q-8] —0-48 1916-1925 .. a 0:58 0-48 0-44 0:08 1926-19385 .. srl 0-50 | 0-18 0-20 0:18 1936-1946* .. Saal 0-89 1-16 1:35 1-72 Mean seul 19208 MEQ | Del 23-41 Nore—_(1) 31° 34’ N., 130° 33’ B. (2) 36° 47’ N., 137° 03’ E. (3) 30° 38’ N., 141° 59’ E. (4) 41° 47’ N., 140° 43’ E. * Mean of eleven years. TABLE II—AMmoOuUNT OF PRECIPITATION DURING SUMMER (MAY—SEPTEMBER) (Deviation from the mean in mm.) s ; | MiddielPachon japanieropers lll Wronmaide: ace. =| | Gifu(1). | Hushiki(2). | © Nemuro(3). Period— | | 1886-1895 .. : sel == BAe Ps OR + 97-97 1896-1905 / |. geese | +139-81 — 60-58 1906-1915 ie epee | + 61-87 7 oe 1916-1925 Ro leresarou) We 53:49 15. G80 1926-1935 .. Pa 158730) yp 20a 4 36-38 1936-1946* .. : | Sei ew |> = 61-82 +. 6:64 . igen ae nei |) asses Nore.—(1) 35° 24’ N., 136° 46’ E. (2) 36° 47’ N., 137° 03’ E. (3) 48° 20’ N., 145° 35’ E. * Mean of eleven years. Iu THE SEVEN HUNDRED YEAR PERIOD IN THE CLIMATE AND THE AURORA BOREALIS IN JAPAN By Hripeo Nis#ioka, Keio University, Tokyo In 1935 Professor Shida, of the Kyoto University, first brought the 700-year wave of climatic change to light on the annular rings of what we call BENIHI, a kind of cypress about 1,050 years old which grows on Mount Ari-san, Formosa. It was, however, not clear whether this wave existed or not in Japan proper. In 1946 I received a report on the annular rings of a Japanese cypress of about 810 years’ growth at Nagano Prefecture, which was measured by Mr. K. Yamazawa, and also I have measured the annular rings of old columns of Horyu-ji Temple, Nara Prefecture, and of old cedar on Mount Koya, Wakayama Prefecture, of old Zalkova acuminate at Utsunomiya City, Tochigi Prefecture, and so on. 500 Ai 500 1000 1500 TLITT TTL A LE LBS a Aiiinveodii ain PRE-HISTORIC AGE HISTORIC Hd Fic. 1.—The wave of 700 year periodic change of climate in Japan According to these measurements, the fact that a 700-year wave definitely exists in Japan has been discovered. It was, however, about two centuries behind that of Formosa—that is, the peak of the wave means the warm periods in Formosa occur in the tenth century and the seventeenth, but in Japan it is in the ninth and the fifteenth. This difference—viz., about two centuries—between the southern and northern districts will suggest some secrets which probably have relation to the fundamental reasons for both of the 700-year climatic changes. At any rate, it is beyond doubt that the 700-year wave of climatic change has occurred not only in Formosa, but i Japan. I therefore continued to pursue further research in this climatic phenomenon. Such a great change of climate marked on annular rings must bring many other historic proofs, and I could fortunately find several points of evidence in many classics, in archeological discoveries and from botanical and zoological points of view, all of which are shown on the diagram of Fig. 1 and included in its explanation. (A) Shell-fishes (Anadara granosa Linne and Sanguinolaria: olivacea Jay) and fishes (Muraenesox cinereus. Forskal, Tylosurus anastomella Cuvier and Valenciennes and Tatus twmifrons Temminck and Schlegal) living in warmer water than there is at present in Tokyo Bay were taken by the Stone age people for sustenance and formed the shell-mounds of Shimogumi, Shimokuchi, Kayama, Moroiso in Kanagawa Prefecture and other places. 118 (B) The lower shell-stratum of Yoshii and Orimoto shell-mounds in Kanagawa Prefecture contained’ many Anadara granosa Linne, but in the upper stratum there are no traces or very few of them. These facts indicate that the climate and the sea-water dropped in temperature from a previous warmer period. (C) We cannot find shell-fish such as Anadara granosa Linne, but shell-fishes (Natica janthostoma Deshayes, Mactra sachalinensis Schrenck, Cancellaria condulifora Sowerby, Pecten laqueatus Sowerby, Panope japonica Adams, and Neptune arthritica Bernardi) living in cold currents were discovered from shell-mounds such as Takakuneda, Miyadaira, Sakura, and Komatsugawa in Ibaragi Prefecture. (D) The temperature of the climate and sea-water changes again and becomes warm, and Anadara granosa Linne are found in the Fumi- gaoka shell-mound, Kanagawa Prefecture, the Kaminumabe shell-mound in Tokyo, &c. (E) Shell-fishes living in cold water were taken again from the shell- mounds of Kasori, Ichinomiya, and Ishigamidai in Chiba Prefecture, which, from the archeological pomt of view, chronologically belonged to a later type of shell-mound in Japan. (F) Some special kinds of human clay-doll which seemed to be wearing snow-goggles like Eskimos or Siberians to protect their eyes from glare were found from ancient sites in the northern provinces of Japan. (G) Horse-chestnuts were excavated from many ancient sites. There ~ are none of such plants existing in those places at present. We can see these plants in cooler places, such as in high mountains or in the northern provinces. (H) According to the poems in “ Manyo-syu,”’ flowering season of the cherry trees was seen about a week earlier than nowadays. (I) According to the “ Taiheiki,” Vol. 5, Daito-no-miya, an Imperial Prince, ate rice-gruel containing’ horse-chestnuts in the mountains, Nara Prefecture, where this kind of nut at present is hard to get. (J) “ Tosha-Shinko-ki”’ records that Lake Suwa, Nagano Prefecture, did not freeze even in the winter for eight consecutive years from 1511 till 1518. The cherry blossoms bloomed earlier than it does now. (K) “Tonegawa-zushi’”’ (1858) and “Kii-no-kuni Meisho-zue”’ (1851) mention and sketch these facts—namely, that sea-lions came down to the south even to the coast of Chiba Prefecture all the year, and to some islands of Wakayama Prefecture in the winter season. According to “ Setsu-yo-kikan,”’ the water of all rivers at Osaka Province became ice in the winters of 1813, 1822, and 1823. (L) The modern atmospheric temperature not only of Tokyo, but of every part of Japan, is becoming higher than in the past, according to the meteorological observations during this century. _ Then why does the seven hundred year periodicity of climatic change happen? This is a very interesting problem, and I have found recently one of the keys to give a solution to it. Since the seventh century we find Hay) fifty-two records of the appearance of Aurora Borealis (northern lights) in Japan in our old documents such as “* Nihon-shoki,” “ Azuma-kagami,’’ &c. These records are shown in the following table :— List oF AURORA BOREALIS IN JAPAN No. Date. Location. || No. Date. Location. 1 2 Jane, 62114) Nara: 2 —— aml OOlme .. | Kyoto. 2 21 Sept., 683 | Every part. 28 lis} Wiebe. - sls ysyy Se .. | Kyoto. 3 14 Aug., 839 | Kyoto. 29 14 Mar., 1587 .. .. | Kyoto. 4 25 April, 843 | Kyoto. 30 (ASepiswl OSDir. .. | Tokyo, Osaka, &c. 5 — June, 939 | Kyoto. 31 Summer, autumn, winter, 1637 | Tokyo, Kyoto, &c, 6 29 Mar., 1098 | Kyoto. By. — july, 1656 .. .. | Tokyo. uf 29 July, 1119 | Kyoto. 3 ZimOct mG isieer 56) || IRGOUCL, 8 19 Aug., 1150 | Kyoto. 34 ZoeDecmilG93i. .. | Ishikawa. 9 15 Oct., 1150 | Kyoto. 35 Ta Novse i726. .. | Kyoto. 10 17 July, 1152 | Kyoto. 36 16) AE, We) sis .. | Shiga. ‘ ial 13 Dec., 1170 | Kyoto. 37 ifs) IDYO.3, | UB dc .. | Tokyo, Kyoto, &c. 12 12 Dec., 1176 | Kyoto. 3 Nee Seite, AAD oc .. | Every part. 13 21 Dec., 1177 | Kyoto. 39 2b SeptawladOmer .. | Kyoto. 14 26 Dec., 1202 | Kyoto. 40 UWP) Ovens eel oc. Bo |) HSVOUCL 15 28 Feb., 1204 | Kyoto. 41 () Jains, Sirs S. aa @hiba 16 27 Jan., 1205 | Kyoto. 42 L Mars li786) se .. | Nagoya. ity 8 Sept., 1227 | Kamakura. 43 22 Sept., 1810 .. .. | Tohoku 18 24 Mar., 1241 | Kamakura. 44 24y Sept. 1822: .. | Osaka. 19 17 Aug., 1247 | Kyoto. 45 26 Nov., 1855 .. .. | Osaka. 20 7 Aug., 1363 | Kyoto. 46 2 Sept., 1859 .. .. | Wakayama. 21 4 Nov., 1370 | Kyoto. 47 416 Bebs) 1872 5. .. | Shimane, Shizuoka. 22 3 Dec., 1370 | Kyoto. 48 ZoeSe ptm 0S ... | Ehime. 23 — Oct., 1371 | Kyoto. 49 KS} Ooyins WAS g .. | Sapporo. 24 21 Sept., 1440 | Kansai, Aizu. 50 22; 26° Jan:, 1938) 5. .- | Lwate. 25 23 Aug., 1455 | Kyoto. 51 31 Mar., 1940 .. .. | Rishiri. 26 15 Oct., 1486 | Kyoto. o2 Wier ane 5 .. | Anbetsu. | The monthly frequency of the aurora in Japan bears a resemblance to that of the auroree which have been observed in other countries— Norway, Sweden, Denmark, and so on (Fig. 2). It is already known that the aurora increases and decreases its number of appearances every eleven years in accordance with the periodicity of the sun-spots. But now I have found that the frequency of the aurora in Japan has some relation to her 700-year periodic change of climate—that is to say, most of the aurore have been sighted in the century of colder period, and that in warmer period there are few or none. I have also proved that this tendency is-even more conspicious in Korea (Fig. 3). Unfortunately, we cannot get the records of the aurore in Korea documents except - during the period from the eleventh to the seventeenth century. In these records, however, are counted up two hundred and three aurore. At any rate, it is very interesting to know that there exists a definite connection between the frequency of the aurora and the 700-year periodic change of climate in Japan. Because the aurora appears as the result of the influences of electrons from the sun upon the magnetic fields of north and south of the earth in the upper region of the atmosphere, the appearance of the aurora has a close connection with that of the sun-spots as already known. And so the 700-year periodic change of climate may also be due to.some influences caused by the changes in the solar activity. The fact that the frequency of the aurora in Japan has similar periodicity with the climate will provide a serious subject to study on this problem. 120 Pe ee| nl Wael ~~. JABAN [LI Ce = i Nish vokat | SPAN EIANS WAY JHE SLY AWG SPT OCT NOV DE 15 a By ie DENA te ~ “aaey Xa Fie. 2—Comparison of monthly frequency of Aurora on 2D >m ce Am Og > Ba LTT yn 7 | . ae Ma ‘ AAOY aN, ‘ ey 0 4} ob7 47, WAVE OF hi ty oa me 11, TOOYERR PERIODIC 7 Gea Eo WL, G4, ‘eo Dae “CHANGE OF CLIMATE 7% 5 i z] - pppel its Ja 30% (yi) NM SPRAN “i yy y oe H NISHIOKA ¢ LLIN IIOP “ ; PET FL Ll Fic. 3.—Frequency of Aurora in Japan and Korea 121 THE ARID BOUNDARY IN EASTERN ASIA By Eticuiro Fukui, Japan In order to consider the effects of precipitation upon practical problems the absolute amount of precipitation alone is not satisfactory. Especially from the agricultural and pedological point of view, precipitation excess or precipitation minus evaporation has most significance. On the other hand, the evaporation is remarkably influenced by the temperature, so that the precipitation and the temperature are the most important factors to determine the boundary between the arid and humid regions. For this purpose many formule involving the precipitation and temperature have been found. Although these formule apparently are of different types, we can transform them into the same functional expression. CHART OF ARID BOUNDARY W. K6éppen expressed the dry limit by the precipitation and temp- erature. Annual precipitation 7 fem.) on the boundary line which separates the stepp climate from the humid climate is given by the empirical formule y = 2 (t+ a) where ¢ is the annual mean temperature at the station and.a is a numerical constant. 122 Similarly, the annual precipitation 7 on the boundary line between the stepp and desert climate is given by y=tta F. R. Falkner (1938), based on climatological study in Africa, expressed the arid boundary by the following formule ab OtOr 4 —ti- 12 This is the same form as Koppen’s. Emm. de Martonne’s aridity index D, the most famous formula, is given by — Ip ns — t+10 where P is the annual precipitation (millimetre), and ¢ the annual mean temperature (°C.). R. Rang’s rain-factor (“ Regenfaktor’’), based on the pedological point of view, is also the similar form D1 nae t These two formule are generally expressed by le D = —, t+ Bf and D! is considered to be a special case when B = O. Martonne considered that the outer limits of land utilization and agriculture comcide with the line which connects the points where D is 20. : Hence if we express P by centimetres instead of millimetres, the upper formula becomes P= 2(¢ +8) which is the same as Koppen’s. C. W. Thornthwaite called the ratio of precipitation to evaporation by the name of “ P-E ratio”’ and empirically expressed it by Pl el Pe Nae E == || ]lo5) (=) where P is the annual precipitation (inch) and F the annual mean temperature (°F.). If we choose the unit of millimetre and centigrade instead of.inch and fahrenheit respectively ; P P ot eae Ceo Now we define the dry limit where the annual amount of precipitation equals the annual evaporation, or P—E ratio is 1-0, the upper formule becomes P = 3-6 ¢ + 12:2) This is also similar in form to K6ppen’s, except that the numerical constants differ a little. Hence the formula devised by many authorities reduce to the same form. But the numerical constants must be different with respect to the individual regions and not unique in the wide area of the world 123 Especially in eastern Asia, the climatological conditions are very different from other continents and the above-mentioned formule are not applicable by themselves. In eastern Asia evaporation is observed at few stations, and ample material is not obtainable. Now the observational data are collected as much as possible in Japan, Manchuria, China, and East Indies. Through previous study we ascertain that the annual evaporation is related not only to the temperature, but also to the amount of pre- cipitation, but the mutual correlation is not the same with respect to the individual regions. So we can express the annual amount of evaporation E by the linear function of temperature ¢ and precipitation P. E=a+bt—cP The constants a, 6, and c are determined by the method of least ‘squares in each region, and the following results are obtained. Japan : E=790+-32-8/—0-03P Manchuria: E=—1375-+-50-7¢—0-09P China =—3506—— Iie O-4 Ol East Indies: E=449+-297—0-13P Theoretically the arid boundary may be chosen where the amount of annual evaporation equals that of the precipitation. But practically the amount of evaporation measured by instruments in general use in Japan and other countries is too much as compared with the real value. ‘Sometimes it reaches twice the evaporation from the field surface. Moreover, a part of rain-water runs down into the ground and it is clear that the precipitation equal to evaporation does not give the arid boundary. However, as these details are not completely known, I assumed temporarily that the arid boundary is located where the annual amount of precipitation is half of the annual evaporation. Only in the East Indies, where the Wild’s atmometer is used, the boundary is taken where the annual amount of precipitation is equal to that of evaporation. Thus the annual amount of precipitation P on the arid boundary line is given by the following formule. Japan: P=387-+-15:88 Manchuria: P=206-+18-5t China -R—1463==497 East Indies: P=397 --25:6¢ So, if the actual amount of precipitation at any place is larger than the calculated value P, it belongs to the humid climate and vice versa. For example, the calculated value P in the East Indies is 1,040 mm., and actually no station belongs to arid climate. The whole of Japan also belongs to humid climate, while a part of Manchuria and China represents arid climate. The boundary line is shown in the map. The northern half of China and the eastern part of Manchurian mountainland belong to arid region. Actually this boundary line agrees well with the distribution of plants and geographical land- scape—for example, the northern limit of rice-cultivation. 124 SYMPOSIUM ON RESEARCH NEEDS AND TECHNIQUES IN PACIFIC METEOROLOGY CONVECTION CURRENTS IN THE ATMOSPHERE OVER A SOURCE OR EAT By Sir GEOFFREY TAYLOR, Cambridge University | Abstract} This paper shows how the heat in a vertical convection’ column spreads out and how high it penetrates when a given supply of heat is released into an atmosphere with a given vertical distribution of temperature. The studies were carried out partly in connection with the dissipation of fogs on aerodromes by supplying heat, and partly during work on the atomic bomb at Los Alamos. DISCUSSION Mr. Hutchings pointed out that Sir Geoffrey’s results would be very useful in the problems of orchard heating for frost protection, while Dr. Spilhaus pointed out that they could also be very useful in the problems of waste disposal. Mr. Simpson gave an interesting discussion on aeroplane flights over the volcanoes of Hawaii, and the results obtained in this way for the temperature distribution seemed to agree qualitatively with Sir Geofirey’s conclusions. Mr. Priestley remarked that Sir Geoffrey’s analysis showed the excellent results that could often be obtained by very simple methods. CONTROLLED ALTITUDE BALLOONS AND VERTICAL MOTION De the IGE AlMOSPHP RE By ATHELSTAN F. SpitHaus, University of Minnesota [A bstract| ; Flights with high altitude balloons controlled so as to fly at constant pressure surfaces are described, and certain features of the trajectories of the balloons are discussed.’ During several flights it was noticed that the barographs carried by the balloons recorded oscillations with periods between approximately one and ten minutes. Since these periodic height variations cannot be attributed to the mechanism maintaining the level of the balloon, they must be attributed to real oscillations of the atmosphere. The lengths of the observed periods agree very closely with those computed from the observed lapse rates of temperature. The vertical velocities associated with these oscillations range up to 1,000 ft. per minute. DISCUSSION In answer to a question by Mr. Priestley, Dr. Spilhaus said that at present the control was not sensitive enough to measure very accurately small vertical velocity, such as, for example, that due to subsidence. 125 One point of interest mentioned by Dr. Spilhaus was that the trajectories of the balloons do not agree very closely with the trajectories computed from the geostrophic winds. The deviation was always towards regions of lowest pressure. Dr. Spilhaus mentioned that oscillations observed in the pressure-recording apparatus carried by the balloon had been observed on a number of occasions, but it is not yet certain whether they are oscillations of the atmosphere or of the balloon. GLOBAL TRANSPORT OR ABAD VAN DE MOMENT wiv By C. H. B. Priestrey, C:S.1.R., Melbourne, Australia [A bstract) Global transport of mass, heat, water vapour, momentum, vorticity, &c., are irregular processes whose irregularities are on the scale of cyclonic and anticyclonic disturbances. A quantitative study of these transports is required before we can approach a full understanding of the average distribution of these elements, and, further, of the variation in distribution with season and differences between one year and another. Probably the first part of the problem to be faced relates to the mean distribution with latitude. In this the meridional transport is the significant quantity. Within any latitude zone there are processes occurring which left to themselves, would effect a more or less continuous loss or gain of the elements concerned—for example, a high-latitude zone would cool in virtue of an excess of outgoing over incoming radiation, a zone in the westerlies would slow down through surface friction, and so on. Relative to the magnitude of the non-conservative influences, the mean conditions in any latitude zone change, if at all, very slowly. In a study of the mean latitudinal distribution it may be adopted as a working principle that the loss or gain of heat, momentum, &c., is compensated by transports from adjacent zones. In the case of mass, where no non-conservative process is involved, the mean transport across any latitude must be zero. The technique for evaluating these transports has been described elsewhere (see references), together with a discussion of the results obtained from upper-air data at Larkhill covering a period of two years. Further evaluations have been made from. a year’s observations at Norfolk Island (29° S. latitude) and some isolated two-monthly periods at various stations in or near 10° latitude in the Western Pacific Region. The wind data available did not go above 400 mb. with sufficient regularity to permit evaluations above that. level; so the results are indicative rather than quantitatively exact. Certain tentative conclusions may be _ drawn :— (1) A reversal in the troposphere of the eddy-flux of heat, a typical feature at Larkhill, is evidenced also at Norfolk Island.. (2) The percentage of the total eddy-flux of heat which takes place in latent form increases from about 50 per cent. at Larkhill to about 70 per cent. in latitude 10°. (5) Great care must be taken to obtain representative data in low latitudes, and more than one ascent per day may be necessary for an accurate evaluation. 126 (4) The mean eddy-flux of momentum found for the year at Norfolk Island was 0:16 x 10° dynes/cm., in such a sense as to exert an eastward pull on the tropical zone. From this result the eddy-flux of momentum, or total Reynolds’ stress across latitude 30°, does not appear to maintain the surface easterlies on the equatorial side nor the wide belt of westerlies to pole- ward. For the maintenance of these mean zonal flows we require a far larger poleward flow of westerly momentum across this critical latitude, and this momentum transfer must inhere in the mean flow pattern. A toroidal circulation, with . poleward component of flow at the level of maximum wind (jet stream), would supply a transfer in the mght sense. The danger of the geostrophic wind assumption in these studies is to be emphasized. (5) The total eddy-flows of heat in all these latitudes are of the mght sign and magnitude to compensate for the radiation losses and gains. But since mean toroidal flows, which are necessary for the mass and momentum balance, must bring about a large net flow of heat (see references), it is clear that the mean tempera- ture and moisture distributions are not to be explained in terms of eddy-transport alone. REFERENCES Priestley, C. H. B.: U.G.G.L. (Oslo), 1948. Quart. Jour. Roy. Met. Soc., Jan., 1949. DISCUSSION In reply to a question by Mr. Andrew Thomson as to whether stations on meridians or on parallels are more useful, Mr. Priestley rephed that, ideally, both were required, but in the event of only a few stations being available those on different parallels of latitude would be most useful. In answer to a question by Mr. Hutchings, Mr. Priestley said that the unavoidable slight errors in temperature given by radiosonde data were not a serious limitation in this work. What was required was continuity in time. ; NEW METEOROLOGICAL INSTRUMENTS By ANDREW THOMSON, Controller, Meteorological Service of Canada | Abstract] 1. The Meteorological Service of Canada has recently developed the Gill hydrogen generator which will produce about 100 cu. ft. of hydrogen in about eight minutes at a maximum pressure of 3 lbs. per sq. in. The process employed is to add water at a controlled rate to a mixture of flake caustic soda and aluminium turnings. The reaction produces much heat and steam, which is quickly removed by passing the gases through boiler tubes filled with a cooling solution. After the reaction is completed the residue can be washed out easily, and within two minutes the generator can be made ready for generating another charge of hydrogen. 2. There has also been. developed (along the lines of the Robitsch pyrheliometer) a solar radiation instrument which will record mechanically the total amount of solar radiation falling on a horizontal surface. A 127 maximum discrepancy of 5 per cent. has been found between Eppley instruments and the new pyrheliometer, and this amount can be reduced while sealing the record. A seven days’ record is obtained on a chart placed on the conventional spring-driven drums revolving once a week. DISCUSSION In reply to a question by Mr. Ewing, Dr. Thomson said that the hydro- gen generating instrument could probably be adapted for use with ferro- silicon instead of aluminium. With regard to the pyrheliometer, Dr. Spilhaus suggested that it would be advantageous if it could be adapted to stand the rolling that takes place on weather ships which at present affects the accuracy of observations taken aboard these vessels. With regard to observations in the Arctic, Dr. Priestley raised the question of how one might distinguish between falling and drifting snow, and in reply Dr. Thomson said that no practical method had been found of making this distinction. J AUSTRALIAN EXPERIMENTS. IN ARTIFICIAL -RAIN FORMATION By E. Bowen, C.S.I.R., -Austraha EXPERIMENTS on the artificial production of rain by the dry-ice process have been conducted by C.S.I.R.’s Division of Radiophysics since January, 1947. The main purpose of the investigation is to obtain a proper understanding of the physical processes which occur when dry ice is dropped into subfreezing clouds. The experiments are carried out by C.S.1.R. personnel in aircraft of the Royal Australian Air Force whenever suitable clouds exist in the vicinity of Sydney. These are nearly always found within about 200 miles, mostly over. land, but sometimes over the sea. The majority of the tests have been made with cumulus cloud, as this is the type most frequently encountered in New South Wales, and it has been found by experience that deep cumulus clouds give the heaviest precipitation. Experiments have also been made with shallow stratus and alto-cumulus cloud, and although precipitation is often induced, in few of these cases has it reached the ground. The quantity of dry ice used has varied, from 50 Ib. to 300 Ib. dispensed at a rate from 10 1b. to 30 1b. per mile but there is no evidence to show whether different quantities produce different effects. The dry ice is broken into fragments, the majority of which have an effective diameter of about | cm. Before an experiment is performed, measurements are made of the clear air temperature and humidity in the vicinity of the selected cloud and careful observation made to ensure it does not already contain large drops or ice particles. In some cases flights are made through the cloud before and after seeding with dry ice and observation made of the type of drops and particles encountered and of the vertical air velocity. Visual and photographic observations are made from outside the cloud, and in some cases they are supplemented by 10 cm. and 25 cm. air-borne and ground radar sets. 128 NUMBER OF SIGNIFICANT EXPERIMENTS Thirty-eight complete experiments were made up to 25th August, 1948. In the majority of these rain was observed to fall from the selected cloud after it had been seeded with dry ice. The most con- vincing proof that this was brought about by the dry ice is the great number of occasions on which the top of the cloud was observed to change from water drops to ice particles and on which precipitation fell from the cloud shortly after seeding, while similar clouds in the vicinity showed no such change. A full description of the experiments and of the main results is being published shortly in papers by Squires and Smith in the Australian Journal of Scientific Research. DEDUCTIONS FROM THE OBSERVATIONS In making deductions from the experiments, eighteen of them have been rejected either because the prevailing weather conditions made observation difficult or because there was some doubt whether the rain which fell was in fact caused by the seeding process. In the remaining twenty the observations were adequate and the conditions were suffi- ciently stable and clear-cut for the results to be known with certainty. The main deductions which can be drawn from these limited data are as follows :— (a) The Effect of Cloud Temperature—It is found that the chances of successfully producing rain increase as the temperature of the top of the seeded cloud decreases below zero. Of the twenty tests being considered, precipitation was produced in fifteen cases and quite definitely not produced in five, as detailed in the table. ws . . ercentage Cloud-top Temperature. Bee Bee otie: of Positive | esults. | 0to— 3... 2 2 50 = 424i = 7 a4 3 2 60 — 8to —I11.. 5 0 100 == 112) 160) 15) os 5 0 100 — JG; toe 9S 0) 0 ays —20 to —23 .. 0 1 0 Total 15 5) 75 Four of the five failures occurred between 0 and —8°c. All ten experiments between — 8° and — 16° c. were successful, and there was a single unexplained failure at —20°c. Although temperature has been chosen as a convenient parameter for estimating the probability of success it is obvious that the growth of ice nuclei in the cloud is influenced by a number of other factors, including the degree of supersaturation, the total water content, and the time for which the nuclei are exposed. It is not suggested that temperature is the sole controlling factor. Any of the above either individually or collectively might influence success or failure. 129 5—Pac, Congress (6) Interval Between Dropping of Dry Ice and the Appearance of Rain. —In each of the experiments careful observation was made of the time- interval between dropping the dry ice and the first appearance of pre- cipitation or rain from the base of the cloud. If this is plotted against cloud thickness, there is a distinct tendency for the interval to increase with increasing cloud depth. It appears that the time-interval is in two parts—a gestation time of about ten minutes and an additional time which is a function of cloud thickness and might therefore be related to the rate of fall of precipitation within the cloud. (c) Rough observations have also been made of the intensity of precipitation and when plotted against cloud thickness it is found, as one might expect, that there is a distinct tendency for rain intensity to increase with cloud thickness. CONCLUSIONS The number of occasions on which the top of cumulus clouds have changed from water drops to ice particles and on which precipitation has been observed to fall from the base of the cloud after being seeded with dry ice while similar clouds in the vicinity remain unchanged is convincing proof that rain can be induced to fall artificially. The chances of success are found to improve with decreasing temperature of the cloud top and are greatest at temperatures between —8° and —16°c. It appears that the interval between seeding and precipation from the base of the cloud is a function of cloud thickness and that the intensity of precipitation is also a function of this thickness. DISCUSSION Mr. Mordy, of the Pineapple Research Institute of Hawaii, gave an account of the experiments being conducted by the Institute, and described the techniques that had been developed. Mr. Mordy urged caution in the interpretation of these results which were in the process of evaluation. Mr. Andrew Thomson, of Canada, said that in Canada many similar experiments had been carried out, particularly with regard to the pro- duction of snowfall. He said that in clouds at temperatures below freezing rainfall always resulted, while clouds at temperatures above freezing gave no rain. The maximum amount of rainfall measured was in the vicinity of two-tenths of an inch. Some experiments had also been made in Canada using silver iodide instead of dry ice, but it was found that the silver iodide was not nearly so effective in the free air as it had been found to be in experimental cloud chambers. Numerous cases had occurred also of dry ice causing the formation of clouds in clear air and the production of holes in strato- cumulus clouds. Mr. Simpson, U.S. Weather Bureau, Hawaii, described similar experi- ments in the United States and stated that although results had been rather negative up to the present, the experiments were still being actively continued. In answer to a question by Dr. R. G. Simmers, Mr. Mordy stated that in Hawaii most of the experiments had been on geographically persistent clouds. 130 In reply to a question by Mr. Unwin, Dr. Bowen stated that there were no obvious reasons for the few unsuccessful cases that had occurred in his experiments ; in fact, the appearance of the cloud in the successful cases had not differed materially from the cloud in the unsuccessful tests. In reply to another question he said that there was a possibility of seeding the cumulus type of cloud from below by making use of the up-currents that are always present in these clouds. He believed the experiment had been tried, but this method was not used in Australia. THE BEHAVIOUR OF WATER IN ITS VARIOUS PHASES AT LOW TEMPERATURES AND ITS APPLICATION TO METEOROLOGY [A bstract| By B. M. Cwitone, Victoria University College This paper describes in some detail a series of experiments on the properties of water, particularly with regard to phenomena of condensa- tion. Various different characteristics possessed by certain metallic surfaces and their effects on the condensation of water vapour are discussed. The properties of silver iodide are also discussed, and some insight is given into the effectiveness of these nuclei in the seeding of clouds for the production of rain. A FORM OF POTENTIAL GRADIENT SONDE APPARATUS By K. KREIELSHEIMER, Auckland University College [A bstract| The method of modifying the Bureau of Standards’ Radio-Meteoro- graph for the measurement of the potential gradient in the atmosphere is explained. The method is based on the current due to point-discharge under the influence of the electrostatic field surrounding the earth. Various demonstrations are given to show the effect and the extensions required to the method to record both small and large gradients with sufficient accuracy. The calibration of the sonde and the factors affecting the measurements are discussed in detail. The research is concerned particularly with the disturbed conditions due to thunderclouds and the charge distribution within these clouds. ON THE SEGREGATION OF THE SEA-SALT COMPONENTS AND IMSOBIOR IDUS IO SIUSU ITN ION SUS, EUR By KEN SUGAWARA, SHINYA Oana, and TADASHIRO Koyama, Nagoya University, Japan [A bstract(*) | It was shown that the chemical composition of the wind-borne salt from sea varies so that Ca/Cl and SO,/C1 increase horizontally, as it recedes from sea beach towards inland, and also vertically, as we go from sea-level upwards. The horizontal variation was proved in two different ways—the one, by the comparision of the chemical analyses of more than one hundred rain samples from three different stations, differing in distance from sea, and the other, by that of the salt which (1) A fuller account will be published in Bulletin of the Chemical Society of Japan, Vol. 22, No. 2. 131 was caught by pine-needles from the air. The vertical variation was shown by the comparison of three different kinds of meteorological water substances,—the ordinary rain-water from 500-1,000m., the fog-ice from the summit of Mount Fuji (3,376 m. high), and the water of thunder- storm, originating at a height of 4-15 km. The cause of such distribution of wind-borne salt in the air seems to lie in the partial crystallization of the wind-borne particles of sea-water by evaporation, with production of at least two kinds of daughter particles. The one, hygroscopic in nature and consisting mainly of Na, Cl, Mg, &c., is unstable and falls down earlier from the air, while the other, crystalline in nature and consisting mainly of the sulphates of Mg and especially of Ca, is stable and thus remains longer in the air. As to the processes of the earlier falling down of the unstable com- ponents, two kinds of way were pointed out—the one the selective washing by rain, and the other the selective capturing of the unstable components by various extrusions on the earth’s surface, for instances, edifices, shrubs, woods, &c. PROGRESS OF METEOROLOGICAL INVESTIGATIONS IN JAPAN SINCE 1939 By Kryoo WapbatI, Central Meteorological Observatory, Japan THE special feature of the meteorological investigations since 1939 is the strong tendency to application in consequence of the war. Many papers have been published until the year 1941, but the number of publications began to diminish thereafter owing to the Pacific War. In 1943 the publication of papers with subjects relating to war increased temporarily, but since 1944 research activity was almost stopped until 1946. Though it is now recovering to the pre-war condition, there are many difficulties left to be overcome. Meteorological investigations are made mainly by the scientists of the Central Meteorological Observatory and partly in the Tohoku, Tokyo, Kyoto, and Kyushu Universities, where the professorship for meteorology is established. On the other hand, the Low Temperature Research Laboratory in the Hokkaido University and agricultural experimental stations belonging to the Ministry of Agriculture and Forestry are performing meteorological studies of their concern. As the societies established for the meteorological study the following are to be mentioned : the Meteorological Society of Japan, the Marine Meteorological Society, the Agricultural Meteorological Society, and the Japan Society of Snow and Ice. The most remarkable progress made since 1939 should be found in the project of long-range forecasting, especially that for few days. From 1939 through 1943 K. Takahashi analysed weather changes over Japan. He also studied the method to extrapolate the tracks of highs and lows a few days and showed the possibility of forecasting covering a few days. In 1940 H. Arakawa found the importance of wind aloft on the fore- casting for a week, and studied statistically the variation in the at- mospheric circulation. In 1943 Y. Nakata tried to extrapolate com- plicated variations as in daily pressure and temperature, dividing them into short and long periodic components. Since 1946 A. Fukuoka devised to analyse pressure oscillations into stationary components. Since 1943 M. Ogawara investigated the long-range forecasting by means 132 of comparing method of similar weather charts, while T. Yazawa and others studied long-range forecasting by means of five-day mean weather charts and classification cards. With respect to seasonal forecasting, weather stations in the Tohoku district are co-operating under M. Morita, Director of the Sendai District Central Meteorological Observatory since 1941, in relation to the bad harvest in this district. The results obtained are published in the Journal of the Connecting Society in the Tohoku Meteorological Organi- zation. In these investigations, making use of periodic changes of climate and the relation between climate and drift-ice, remarkable progress has been made in the technics of forecasting, but with respect to scientific or physical basis of the method further studies are yet necessary. Studies on lows and typhoons were made in relation to the daily weather forecasting by T. Otani, H. Fuchi, S. Ooma, N. Yamada, and K. Takahasi. In 1942 S. Syono treated the lows from the point of view of vortex. H. Arakawa (1941) and Syono (1947) discussed the instability of Siberian anticyclones. In connection with aeronautics, a number of investigations on the upper air meteorology were made, of which special stress was laid upon the improvement of observational instruments. Since 1937 researches on radiosonde and radiotracking were made by D. Nukiyama, H. Yuasa, Y. Shirai, and K. Isono. At present the radiosonde of wave-length variation type is being used. This has been compared with the U.S. radiosonde of frequency modulation type, and it was proved that the accuracy is almost the same for both instruments. Radiosonde and radiotracking are being utilized since 1938 and 1943 respectively. More- over, various sonde instruments for cloud observation, icing observa- tion, &c., are constructed experimentally since 1943. In 1944 D. Nukiyama, K. Tsukamoto, and others began to establish the automatic weather station. Concerning the aeronautics, in 1938 H. Arakawa studied the wintet bad weather of Japan Sea side by radiosonde observations. Later, on the same subject, studies were made by aeroplane observations by the Army Weather Bureau. The heavy snowfall in Japan Sea side is caused by winter monsoon. Studies concerning this problem have been made during the period from 1943 to 1946 by K. Sugiyama, K. Kunu, T. Kawamoto, and others, and the importance of local front has been found as a result. During the years from 1939 to 1944 a synthetic study of cumulonimbus was planned by the Ninth Special Committee for the Protection of Thunderbolt Damage, Japan Society for the Promotio:. of Scientific Researches. In summer of these years S. Fujiwhara, D. Nukiyama, Y. Kodaira, H. Hatakeyama, S. Syono, S. Sakuraba, and others, con- cerning various branches of this study, were despatched to Maebashi and executed this plan. The results obtained were made public by D. Nukiyama, S. Syono, Y. Kodaira, S. Sakuraba, and others. On the other hand, M. Abe studied the development of cumulonimbus by means of moving pictures. At the time the direction-finder for atmospherics constructed by A. Kimpara was also utilized for the study. During the period 1942 through 1943 many studies were made on the weather in. tropical latitudes by the forecasters despatched to those districts. The results obtained were reported by H. Fukuda, K. Hirasawa, S. Daidoji, 133 and K. Fujita, and published, though in mimeographed copies. By these studies the following facts were revealed: (1) in the tropical latitudes the streams of air flowing out from the anticyclones in temperate ~ latitudes form a kind of converging line with a band of cumulonimbus along it, and (2) a weak high develops over the Equator which has great influence upon the weather in the equatorial region. On the other hand, kK. Uwai studied the formation of typhoons on the equatorial front, and T. Otani investigated in 1946 the mechanism and origin of rainy season in the tropics. Concerning fog, an investigation on a large scale was made in 1944 at Hokkaido, by Y. Yoshida, K. Fukutomi, and Y. Miyake, under the leadership of U. Nakaya, of the Hokkaido University. By this, precise measurement of meteorological elements were made ascending to the height of 1,200 m. above the ground by means of a big captive balloon. The state of temperature inversion, diameter, and number of fog particles with their absorbing power for the solar radiation, &c., were investigated and many important results were obtained. This investigation had for its object the artificial dissipation of fog. Also in the same year observa- tions of radiation fog were made by S. Sakuraba, Y. Matsudaira, and Y. Shibata, and a part of results thereby obtained were reported by Sakuraba. In relation to the explanation of visibility, aeroplane icing, and precipitation mechanism, investigations on the hydrometeors as rain, snow, fog, and dust particles were made during the period from 1940 to 1943 by Y. Takahasi, K. Ito, I. Imai, and others. In theoretical aspects G. Yamamoto studied evaporation adopting the theory of boundary layer in 1941, and T. Hagiwara treated the evaporation from rain-drops since 1946. In 1941 and 1942 U. Nakaya studied the “ frost heaving” of the ground, while in 1941 experimental studies of artificial avalanches were made near the Shimizu Pass in the Mikuni Mountain Range by the Ministry of Transportation. In addition to this, R. Saito investigated various properties of snow on the ground. The studies on these subjects were mainly published in the journal Seppyo (The Ice and Snow). In 1939 and 1940 Y. Kato and T. Sato, of the Tohoku University, made an absolute measurement of insolation intensity. In 1940 and 1941 Y. Daigo, M. Nakahara, and E. Fukui studied the correlation between crops and weather, animal phenology, and the climate of Asia respectively. At the agricultural experimental stations of the Ministry of Agriculture and Forestry microclimatological studies since 1943 and studies on the noxious insects of rice were performed from the meteoro- logical point of view. H. Hatakeyama, S. Suzuki, A. Kimpara, and T. Asada made a long study on the relation between fires and weather conditions. Owing to the results obtained by this study, fire warning based upon the weather conditions was put into practice all over the country since autumn of 1947. Also the study of K. Wadati on the air current accompanying cyclones and that of S. Syono on isallobaric winds are to be mentioned here. Moreover, there are many investigations on climatology and meteorology, of which “ the World Meteorological Data,’ “the Meteorological Data of Eastern Asia,’ and “the Aero- nautical Weather Charts,” published by the Central Meteorological Observatory in 1942, 1943, and 1944, are regarded as representative. The following is the list of publications which appeared in this period, most of which are in Japanese. In this list, among those publications treating the same subject, only the latest one is mentioned. 134 List OF PUBLICATIONS WHICH APPEARED IN THIS PERIOD 1939— H. Arakawa: Investigation of Monsoon by Radiosonde Over Toyama City. Report of Aerological Meteorology, 2, 158-181. Upper-air Current and the Long-range Weather Forecasting. Weather and Climate, 7, 444-445. S. Ooma: On the Development of Cyclones in the Neighbourhood of Japan. Journ. Met. Soc. Jap., 18, 243-256. 1941— H. Arakawa : Statistiche Untersuchungen atmospharischer Zirkulationsschwan- chungen. Met. Zeit., 5, 183-184. Stability of Cyclonic Current. Journ. Met. Soc. Jap., 19, 171-175. M. Nakahara: Investigations of the Animal Phenology in Japan. Journ. Met. Soc. Jap., 19, 381-387. Y. Daigo : Studies on the Relation Between Yield of Chief Crops and Weather Factors in Japan. Journ. Met. Soc. Jap., 19, 301-313. S. Syono: Studies on Atmospheric Disturbances. Journ. Met. Soc. Jap., 21, 443-449. 1943— Y. Nakata: On the Periodic Fluctuation of Air Temperature. Journ. Met. Soc. Jap., 21, 402-409. K. Takahasi: Dynamic Climatology in Japan. Journ. Met. Soc. Jap., 21, 27-37. K. Uwai: On Equatorial Fronts in the South Seas. Restricted Report of the Meteorological Studies, 4, 1-92. H. Arakawa: On the Invasion of Equatorial Air Mass Which is the Cause of Heavy Rain in the End of Baiu. D. Nukiyama and S. Syono: Occurrence of Thunder and Upper-air Observa- tions. Report of Aerological Meteorology, 6, 1-32. S. Fujiwhara and Others: Report of Special Thunder Observation. Memoirs of the Cent. Met. Obs. of Japan, 21, 1-320. H. Arakawa: Seasonal Change of Lows Originated in the Neighbourhood of Japan. Sea and Sky, 23, 393, 400. S. Sakuraba: On the Energetics of Vertical Lability. Journ. Met. Soc. Jap., 21, 501-505. 1944. None. 1945— U. Nakaya and Others: Studies of Fog in Hokkaido. Technical Academy, Conference of Mobilization. 1946— M. Ogawara: Studies on the Long-range Forecasting Based on the Statistical Method. Temporary Report of Studies, 6. S. Sakuraba: Studies on Cumulonimbus. Temporary Report of Studies, 4. S. Isigura: Summary of the Study on the Forecasting of Chilo Simplex’s Generation. Report of the Agricultural Experimental Station of Aichi Prefecture. M. Kato: Considerations From the Agricultural Meteorological Point of View on the Relation Between the Condition of Cultivation, and the Generations of Chloropo Oryzella and the Water Temperature of Irrigation. Matsumushi, 1. 1947— A. Hukuoka: On the Analysis of Long-range Meteorological Phenomena Into Stationary Oscillations. Journ. Met. Soc. Jap., 25, 11-24. M. Ogawara : Stochastic Method of Forecasting. Temporary Report of Studies, 24. S. Sakuraba: Investigation of the River Fog. Temporary Report of Studies, 28. S. Syono: On the Mechanism of Generation of Cold Waves. Report of Geo- physical Institute, Tokyo Univ. S. Ogiwara: Evaporation of Rain Drops. Journ. Met. Soc. Jap., 25, 1-11. H. Hatakeyama: Fires and the Weather. (Monograph), pp. 112. 135 OCEANOGRAPHY REPORT OF THE STANDING COMMITTEE ON OCEANOGRAPHY REPORT BY HE .CHATRMAN VOR {iEE INTERNATIONA COMMITTEE ON THE OCEANOGRAPHY OF THE PACIFIC By Tuomas G. THompson (Chairman of the Standing Committee), University of Washington OVER a decade has passed since the present chairman of the International Committee on the Oceanography of the Pacific presented his report to the Sixth Pacific Science Congress which was held in the United States. The international committee at that time was well organized, due largely to the magnificent efforts of Dr. T. Wayland Vaughan, the previous chairman. Most of the members of this committee were chairmen of their respective national committees, and much had been done by them to promote numerous oceanographic investigations in many parts of the Pacific. Since that time we have lived through the greatest war in history. For over six years the efforts of the scientists of the warring nations were diverted to problems of immediate military or national importance, and recently to the perplexing problems of reconstruction. This period through which we have passed has also witnessed marked tendencies for social and economic changes due to the advances in science and technology. The remarkable achievements in aviation have literally produced a shrunken world. The distance from New Zealand to North America, for example, is no longer measured in weeks, but now in hours for traversal. Seattle and Vancouver are closer to Auckland to-day than they were to New York and Montreal twenty years ago. The United Nations Organi- zation has come into being. Within its structure are commissions vitally concerned with human progress through education and scientific research. We, gathered here and representing the scientists interested in the greatest of all the oceans, are most desirous to play a part in furthering the functions and accomplishments of the world organization by giving special attention to the Pacific. During the years of conflict many trends in scientific thought and endeavour were catalyzed. Huge sums of money were made available for research. Programmes of investigation were planned and initiated to a degree almost undreamed a decade ago. The results of these investi- gations used at the time to further the subjugation of an enemy can now be applied in the cause of peace for promoting human welfare and to stimulate the acquisition of further knowledge. Scientists of various specialties as well as nationalities learned to plan and work together toward solutions of complex problems. The results obtained emphasized again the importance of team work. Some months ago the chairman of this Committee on the Oceano- graphy of the Pacific made attempts to reorganize his group in anticipation for the preparation of a report to the Seventh Pacific Science Congress. It was found that some of our colleagues had died, others had retired and still others were of the opinion that they were no longer in a position to 136 speak with authority for their countries or their organizations. The prospects were rather discouraging. However, after correspondence with Dr. Gilbert Archey, Secretary-general of this Congress, a plan of operation was initiated, and I am most grateful to Dr. Archey for his advice and suggestions. There was considerable exchange of correspondence with various governmental authorities, research organizations, and individual scientists in the several countries. Many of the letters received in reply told much the same story—namely, reorganization still in progress to meet peace- time conditions, difficulty of securing equipment and personnel, unsettled conditions, extensive programmes for oceanographic research still in the planning stage, and generally the hopeful anticipation for funds. However, excellent reports were received from many, and these are given in the Appendix attached hereto. Since the meetings of the Sixth Pacific Science Congress much con- centrated attention has been given to the oceanography of the Pacific. This resulted, to a large extent during the war, from the continuous demand of military authorities for general oceanographic knowledge, for details concerning the currents in different parts of the ocean, for the necessity of predicting sea swells and waves, for requests for information concerning the variations and the depths of the thermoclines of many areas, the distribution of temperature and salinity gradients, and the nature of the topography of the ocean bottom in many localities. There was also a demand for information as to the distribution and abundance of fish as a source of food in the several areas. The means of presenting some of these results as well as reports of special oceanographic activities and research programmes of many laboratories will be through the excellent programme arranged by Mr. A. W. B. Powell, organizing chairman of the Division of Oceanography, and likewise the representative of New Zealand on the International Committee. This programme may therefore be considered as part of the report of the International Committee on Oceanography in its attempt to give to the Congress a comprehensive understanding of the recent advances in the oceanography of the Pacific. Undoubtedly the chief factor that has aided in the acquisition of oceanographic knowledge has been the improvement and development of many interesting and useful instruments. Some of these instruments were devised and perfected during the war at the Woods Hole Oceano- graphic Institution in Massachusetts working in co-operation with agencies of the United Kingdom as well as those of the United States. It is interesting to refer to records of earlier meetings of this Pacific Science Association. There are statements there made lamenting the lack of soundings in all parts of the Pacific beyond the continental shelves. It is stated that there was one sounding in deep water for each ten thousand square miles of ocean. The time, labour, and expense involved in securing just one sounding was considerable, and even the accuracy of the soundings available was questioned. The fathometer, an instrument developed during the past several decades in the United States and Great Britain, was further perfected during the war. Sound travels through sea-water at nearly 1,500 metres per second. The fathometer operates on the principle of measuring the time-interval required for a sound emitted from the hull of a vessel to travel to the ocean bottom and there be echoed back to the vessel, 137 where it is picked up by the hydrophone. The impulse received will be amplified electrically and recorded by a stylus moving over a roll of recording paper, the ruled graduations of the paper translating the time-interval into the depth of water under the vessel, or the impulse may be registered by a rotating disk the time-interval required recording as the depth on the rotating disk. Thus by the flick of an electric switch the fathometer is caused to function and the depth of water under the moving vessel recorded in a few seconds. Hundreds of thousands of soundings have been obtained, abysmal chasms and troughs have been charted, and many seamounts have been discovered. Several papers to be presented later will undoubtedly treat the fathometer in more detail and the corrections necessary to be applied to the observed readings for proper geological interpretation. The intensity of the impulse received by the hydrophone will also indicate to a trained observer much about the nature of the ocean bottom. The fathometer has often been used by fishermen for locating schools of fish as the sound is reflected from the backs and sides of the fish, thus indicating the exact depth at which the fish are and the distance from the sea bottom. The bathythermograph is an instrument devised by Dr. A. F. Spilhaus and developed by him and his associates at the Woods Hole Oceano- graphic Institution. Originally it was intended to serve as an instrument for detecting the depth of mixing of the surface waters of the sea by the wind. However, the instrument as now used presents an excellent portrayal of the temperature gradient down to depths of about 150 metres and clearly indicates the depth of a thermocline when one exists. The instrument is being further developed so that records of the temperature gradients to even greater depths may be obtained. The bathythermograph consists of a cylinder with a heavy brass nose- piece. Within the cylinder are sylphon bellows attached to a slide carrier into which a smoked-glass slide is inserted. A stylus, which moves over the slide, is connected to a bourdon tube, which in turn is attached to a coil of copper capillary tubing. The copper tubing contains xylol, and the expansion or contraction of this liquid gives a means for noting thermal changes. The sylphon bellows is a spring that will be compressed 1 in. with a tension of 320 Ib. The adapter, carrying the smoked-glass slide, is firmly secured to the sylphon bellows and moves with the pressure, the indication of depth, on the long axis of the instrument. The stylus, fitted to the Bourdon tube, moves with the temperature change on the transverse axis. A change of 0-1° F. can be detected. Each instrument must be carefully calibrated in a pressure tank at known temperatures and pressures. At present there are two institutions in the United States equipped for calibration of the bathythermograph— namely, the Woods Hole Oceanographic Institution and the Scripps Institution of Oceanography—and in Great Britain at the Teddington Laboratories. The bathythermograph has the decided advantage of being used while a vessel is underway. The observations may be made just as rapidly as the slides can be adjusted, the instrument put in place, then dropped to a given depth and hauled in again. In practice the instrument functions to a depth of about 150 metres, giving a continuous curve showing the changes of temperature with the depth. Within a few hours much detailed information on the nature of a water area can be 138 readily and easily obtained by a number of casts with the bathythermo- graph, and in a far more detailed manner than by the classical methods of reversing thermometers. The exact depth of the thermocline is directly ascertained. Much more information on the bathythermograph will undoubtedly be given by Dr. John P. Tully, of Canada, in the paper he is to present. The salinity-temperature-depth-recorder is a magnificent instrument likewise developed at the Woods Hole Oceanographic Institution, in co-operation with the Bristol Company, for the study of coastal waters and the waters of estuaries where there are considerable changes in the temperature and salinity gradients. During the summer of 1948 Dr. Alfred C. Redfield, of the Woods Hole Oceanographic Institution, and Dr. Clifford A. Barnes, of the Oceanographic Laboratories of the University of Washington, used the instrument with marked success in the study of waters of Washington Sound, which includes the San Juan Archipelago in the State of Washington. These waters are characterized by cold oceanic water that has been upwelled off the coast of Washington and British Columbia and is carried through the Strait of Juan de Fuca northward into Washington Sound. From the north there flows during the summer months the much warmer surface waters from the Strait of Georgia, which represent dilution by the Fraser River. The instrument has also been used by the Oceanographic Group attached to the Pacific Biological Station at Nanaimo, British Columbia, for the study of the waters of the estuaries of the west coast of Canada. The instrument consists of a submersible “ head’’ containing the measuring elements assembly and a deck mechanism fitted with a com- puting and amplifying system for “‘ processing ’’ and recording the measurements. The “ head’’ can be lowered to depths of nearly 200 metres. It contains a resistance thermometer to measure the temperature, electrodes for conductivity, and a Bourdon tube element for pressure. These instruments continuously relay the measurements to the deck mechanism, which computes salinity from temperature and conductivity and translates pressure into depth. The temperature and the mechani- cally computed readings of salinity and depth are recorded simultaneously in lines of different coloured inks on a synchronized paper-strip chart. Temperature with the present instruments available can be measured over a range from —2-0° c. to 32° c. with an error not exceeding 0-1° c. ; salinity throughout a range of 20°/,, to 40°/,, with an error not exceeding 0-3°/,,. The maximum depth error is approximately 2 metres over the range of 185 metres. Vertical profiles of water structure can be taken by lowering the sensitive head of the instrument from a drifting vessel. By towing the head of the instrument just below the surface a horizontal view of the water structure can be obtained along a ship’s course. The quick response and the continuous recording features of the S-T-D adapt it particularly to obtaining the overall pattern of water structure and thermal changes in coastal waters. Coring Devices: Mention should also be here made of the several forms of apparatus used in securing long cores from the floor of the ocean depths and which are bound to play an important role in geological exploration. The first successful device for securing long cores showing the structure of the ocean floors was developed by Dr. Charles S. Piggott, formerly of the Geophysical Laboratory of Washington, D.C. Very recently Dr. Kullenberg, following suggestions of Dr. Hans Pettersson, 139 the Swedish oceanographer, has materially improved the core sampler. With the Piggot sampler cores of 6 ft. to 12 ft. were obtainable, while it is understood that cores up to 50 ft. in length may be secured with the Kullenberg apparatus. It is obvious that these core samplers are a tremendous advance for collecting samples of the ocean bottom over that of putting a chunk of lard on the end of a sounding lead or by the use of a grab sampler. The underwater camera is another remarkable piece of apparatus that has been recently employed and is being further developed by Dr. Maurice Ewing, of Columbia University, working through the Woods Hole Oceanographic Institution. Pictures of the ocean floor and the life thereon have been readily obtained to depths of approximately 200 metres, and last year Ewing was successful in getting pictures to far greater depths. A current meter developed by Commander Roberts, of the United States Coast and Geodetic Survey, is a convenient device for recording coastal currents by remote control over a considerable period of time. The instruments are attached to secured buoys placed in the area where the desired measurements are to be made. At given intervals, depending upon the velocities of the current, the rotator of the current meter makes a contact which produces a radio wave. This radio wave can be picked up at a shore station and recorded mechanically some miles from the anchored buoys. Improvements continue to be made in various types of gear used for collecting biological material, and especially for making quantitative measurements. Here, however, the conditions are vastly more com- plicated, and no advances as revolutionary as the instruments of physical oceanography have been experienced. Information concerning the tides of the Pene area has been materially increased, and the advances that have been made will be given in a paper by Mr. E. C. McKay, of the United States Coast and Geodetic Survey. The nature and the prediction of sea swell and waves has received much attention both from the theoretical and practical standpoint from many oceanographers, particularly those of the United Kingdom and the United States. Much more will be heard on this very important subject through papers that will be presented to this congress. The sea offers much to challenge the chemist and the chemical engineer for producing many types of materials to resist the corrosive and solvent action of sea-water and upon which the organisms living in the sea will not prey and destroy. Many studies on the chemistry of sea-water have been made, especially on the occurrence and distri- bution of some of the elements occurring in small quantities. Interest is being manifested currently in the existence of the isotopes of the various elements in sea-water and marine organisms. Papers to be presented to future congresses of the Pacific Science Association will undoubtedly contain much on the distribution of isotopes and also upon the utilization of radio-active tracers applied particularly to the study of marine organisms. The recovery of common salt, sodium chloride, from sea-water is one of the oldest of industries. This compound, so necessary to life, is also one of the basic raw materials of modern commerce, for it or the elements or compounds derived from it are necessary for the manufacture 140 of hundreds of other substances and materials. Hundreds of thousands of tons of sodium chloride continue to be taken from the sea each year. The technological advances of recent years has caused the erection of enormous plants for the recovery of various compounds of magnesium and bromine from sea-water. In several localities, using very efficient evaporators, water itself is being distilled from the sea and sodium chloride, together with compounds of magnesium, potassium, and bromine, recovered from the brines. With the ever-increasing population of the world the problem of sufficient food supplies is becoming acute in many quarters of the world. Since the cessation of hostilities considerable impetus has been given to the exploration of the sea, particularly of the Pacific, as a source of future food by groups within the United Nations Organization. By treaty between several nations various international commissions have come into being to study fishery resources and to write regulations ensuring intelligent use of these resources. The importance of vitamins to the well-being of man is now universally known. Products of the sea, particularly fish-livers, have supplied great quantities of these spark plugs of nutrition. I well recall some years ago when my colleague Dr. W. F. Thompson, then in charge of the International Halibut Commission, urged the halibut fishermen to preserve the fish livers for sale to pharmaceutical houses. At first the suggestion was considered rather idiotic by the fishermen. To-day, however, the money derived from the sale of halibut livers more than pays the full cost of operation of a fishing-vessel. By-products of the fishing industry are being extensively used as the source of fish-oils, cattle food, and fertilizers. Thus with increasing knowledge of the sea and its products, coupled with advances in technological processes, man is learning to use more effectively the material available to him in the sea. However, in no manner has he attempted to exploit the sea as he has the land. Scientific farming of the land has given rise to greater productivity ; animals have been bred to give greater quantities of milk, or of meat, or of wool. Many and better plants, unknown to our grandfathers, have been created. All of this has come about by an orderly process of research and education, fostered by basic research in the fundamental sciences. Attempts to make the sea more productive, to produce better and more useful marine plants, fishes, and mammals have scarcely been made. Large areas of land were unproductive because of lack of water, but by building dams and bringing water the deserts, rich in nutrient materials were made to bloom and produce. There are vast expanses of ocean unproductive because of lack of nutrient salts, yet from oceanographic studies it is known that a few metres below the thermocline of these barren areas and out of contact with the life-giving energy of the sun are unlimited supplies of nutrient salts. Perhaps some day means may be devised whereby these rich waters will be brought nearer to the surface to promote growths of phytoplankton upon which the fishes and mammals of the sea may graze. The potential energy of the rivers of land areas has been converted to useful electrical energy, but the enormous potential energy available within the sea yet remains to be utilized. Exploration of the continental shelves, using geophysical instruments, is being conducted in many quarters in the search for oil and minerals. 141 The chairman of this committee desires at this time to present the following recommendations for consideration by the Seventh Pacific Science Congress :— It is reeommended that— 1. The several countries adhering to the Pacific Science Association, in which there are extensive facilities for oceanographic research, be requested to form a National Committee on the Oceanography of the Pacific, providing that such a committee does not already exist. 2. Each National Committee on the Oceanography of the Pacific shall name one of its members to serve also as a member of the International Committee on the Oceanography of the Pacific of the Pacific Science Association. 3. The several countries adhering to the Pacific Science Associa- tion in which a national committee on oceanography does not exist be requested to appoint a scientist for service on the International Committee on the Oceanography of the Pacific. 4. The Pacific Science Association shall name the chairman of the International Committee on the Oceanography of the Pacific. 5. The International Committee on the Oceanography of the Pacific shall be empowered to function during the interim between congresses in order to facilitate oceanographic investigations in all countries bordering on the Pacific, to aid in the exchange of oceanographic information, and to assist students and investigators desirous of pursuing their studies and investigations beyond their national borders. 6. The Pacific Science Association request that the Inter- national Committee on the Oceanography of the Pacific be represented on the International Committee of Oceanography set up by the Combined Unions of Biological Sciences and of Geodesy and Geophysics. 7. The Pacific Science Association request that the Inter- national Committee on the Oceanography of the Pacific be repre- sented on any commissions dealing with oceanography within the United Nations Organization. OCEANOGRAPHIC STUDIES MADE BY ARGENTINA By PEpRo S. CasAL, Sociedad Argentina de Estudios Geograticos THESE studies are of great importance to us because the continental shelf which borders our coast is very extensive ; there is a warm current which comes from the north and meets other cold ones (from the ““Malvinas’”’ and the Antarctic) and, besides, the tides of the Pacific and of the Atlantic mutually influence each other in the southern part,: producing physical and biological phenomena which it is necessary to determine with precision. The large Antarctic icebergs sometimes invade the continental shelf for reasons which are as yet unknown. At first we oriented our studies: to the hydrographic mapping of the coast. This has required many years of work because the coast is approximately 5,000 kilometres long and is open to the Atlantic. This necessitates an earnest study of the tides whose amplitude is of great importance to the life in the ports.- Although at the mouth of the Plata River the, amplitude of the hightide is only | metre, more or less, in some ports on the coast the amplitude. 142 is from 12 to 14 metres. In these ports the boats cast anchor at high tide near the coast in order to stay high and dry when the cargo is taken off. In this manner the hulls can be cleaned during the time the ships carry out their operations of loading and unloading by means of horse- wagons, or some other means. We are dealing here with ports or bays in Patagonia, with low density of population, where it is convenient when possible to avoid the use of motor-boats for the transferring of merchandise, animals, &c. We have already installed some important geodetical tide gauges and we plan to have six distributed in the most convenient coastal ports. The tide-gauge net will be completed with other apparatus of the “ patron ” type of which twenty instruments will be installed and twelve or more of the portable type will also be installed. Many of these instru- ments have been in operation for some time, and what is lacking is going to be integrated. This material has been acquired from the United States. The immediate needs of our country in oceanography lie within the Great Continental Platform, and therefore our greatest oceanographic efforts are concentrated here. Thermometers—We utilize reversing thermometers, &c., of the classic type. The same can be said with regard to the dredging and the apparatus used to collect specimens from the bottom in such a way as to preserve their stratification. The dredging which has given us the best results is on the smooth ocean floor, although in certain places the results have been satisfactory on the rough ocean floor. The extractions from the ocean floor have not in general given us good results as specimens of stratification, and a new type is being studied at present. In order to obtain certain organisms which live in the sand or mud, some years ago we designed an apparatus which gave us good results and is easy to set up in the same oceanographic vessel. It is used by towing it slowly. Soundings.—We utilize the acoustic ones and also the sounding-lines in dealing with stations where we wish to determine the oceanographic elements at different depths. Current Meters —We utilize those of simple construction which can be made on board, or the modern type “‘ Gurley,” Eckman, Idrac, which give us the intensity of the currents at different depths with the corre- sponding photographic record. Physical-chemical Elements of the Sea-water.—These are determined in the laboratories on land; the oceanographic vessel only collects the samples. Biological Stations.—In the case of our oceanographic vessel, “‘ Patria,’’ we have a rudimentary laboratory in the open air and another below deck. but the most important part of the work is done in the laboratories on land with data brought from the ship. On our continental shelf we de not have nearby ports for work of this type, except in certain sectors. The same situation exists south of the Strait of Magellan to the Argentinian Antarctic sector. Plankion.—The collection of this important element, which gives us an indication of the biological wealth of certain zones, is made with known methods and nets, but its detailed study is made on land. 143 The Government of Argentina is stimulating oceanography, the study of which lies in the hands of the Navy. At the present various Argentinian officials are studying oceanography in the United States in order to acquire the methods and experience of that country. COMMONWEALTH OF AUSTRALIA: OCEANOGRAPHY OF Ribs PACIETE By H. Tuompson, Chief of Division of Fisheries, Marine Biological Laboratory, Cronulla, New South Wales In Australia most of the oceanographical research since 1939 has been done by the Division of Fisheries, Council for Scientific and Industrial Research, though some small biological problems have received attention in the Departments of Zoology in the Universities of Sydney, Adelaide, Tasmania, and Western Australia. The Hydrographic Branch of the Department of the Navy undertook survey work, particularly in the northern Australian area, during the war. The Bureau of Meteorology, working in conjunction with the Royal Australian Air Force, produced considerable material on weather conditions in the whole area. _ Much of the oceanographical work of the Division of Fisheries of C.S.I.R. between 1939 and 1942 was done by M.V. “ Warreen,”’ the research vessel of the Division. She worked particularly in the waters of south-east Australia, where extensive hydrological and planktological programmes were carried out. The results of the hydrological work are in manuscript form, but portion of the material is to be presented to the A.N.Z.A.A.S. meetings in Hobart in January, 1949. After 1942 the programme was greatly curtailed because M.V. ““ Warreen ’’ went on active service, and only a small staff was left to do this work from land-based stations. Since the war the exploratory work of the Division has been increased, and with four research vessels operating the oceanographical programme will be greatly extended. The following vessels will be working during the remainder of the current year (1948-1949, June) :— 1. F.R.V. “ Warreen,” working in Western Australia, particularly on exploratory fishing tests, but also undertaking oceanographical research. 2. F.R.V. “ Liawenee,” working in Tasmanian Waters on the biology of barracouta, shark, and crayfish, with a hydrological programme to support the biological studies. 3. M.V. “H.C. Dannevig,’’ working for six months off the New South Wales coast, undertaking biological research on the trawl fishery of New South Wales and carrying out a hydrological programme at several stations on the coast from Coff’s Harbour to Eden. 4. F.R.V. “Stanley Fowler,’’ undertaking pearl-shell investigations in the Thursday Island (Torres Strait) area, when a biological survey will be made, and methods of cultivation studied. All of these vessels will work primarily on fisheries biological pro- grammes, but in each case hydrological observations will be made and plankton hauls taken at regular stations. Our oceanographical research in the whole area will concentrate on four main problems :— 1. The Assessment of the Productivity Cycle in Australian Coastal Waters.—This will be done by long-term collection at frequent intervals, preferably monthly, of physico-chemical and biological data at stations 144 adjacent to laboratories equipped to do the necessary analytical work. The physical investigations will be concentrated on circulation, mixing, and light-penetration studies. The chemical investigations will be con- centrated on the level of abundance, production, and degeneration cycle of a number of key nutrients, such studies to be linked with similar in- vestigations into the chemistry of bottom deposits and of the adjoining estuarine and fluviatile waters. The biological investigations will be devoted to a study of the annual and seasonal level of abundance and of the growth cycles of a number of key organisms and plankton groups. Up to the present, investigations on this problem have been carried out in the South-east Sector, so that the collection of the chemico-physical data, with the exception of submarine light penetration, has been done over a period of five years in the case of the initial station off the site of the Laboratory at Port Hacking, and for a shorter period at a number of later established stations. The data from oceanographical investigations have been supple- mented by an extensive estuarine programme which has been carried out for approximately five years. Steps are now being taken to collect the light penetration data and to begin a chemical analysis of bottom deposits in this sector. In the South-west Sector a similar level of investigation has been reached, although, owing to the nature of the shelf, the sampling stations have been extended into section lines at each point of the investigation, and an estuarine programme has been carried out at the same time. In both sectors plankton sampling has been confined mainly to surface, with occasional oblique and vertical hauls, using standard N70 “ Discovery ’’ nets. A considerable extension in the study of diatoms and bottom flora and fauna will be necessary to supplement the biological information now available for these areas. 2. The Study of the Circulation Trends in Australian Waters.—In the South-east Sector data were collected by F.R.V. “ Warreen”’ prior to 1942, although the working of section lines was not commenced until August, 1940. Owing to wartime exigencies these section lines could not be worked sufficiently wide to enable sampling in the core and beyond the east Australian current system. For these reasons, although the broad details of onshore circulations are known in this sector, considerable supplementary work is necessary to supply this missing information. In the South-west Sector, F.R.V. “ Warreen ”’ has commenced a deep- sea programme of oceanographical research, working 100-mile section lines as frequently as possible in selected areas. 3. The investigation of the productivity aspects of upwelling in the North- west sector.—The only oceanographic data available for this area have been collected by Japanese pearlers, and these indicate that the centre of occurrence of the upwelling occurs about lat. 20° S. in the spring period, and is distributed over about 150 to 200 miles on the continental shelf. _ A certain amount of preliminary data will be collected by “ Warreen,”’ but a deep-sea vessel capable of independent working would need to be based on Broome or Darwin to work section lines at regular and frequent intervals, to give data on the physical processes of upwelling. 145 4. The Study of the Oceanography of Australian Waters in General.— At present very little data are available for the Australian section of the area to the north of the Continent. Work could be most easily carried out from a deep-sea vessel based at Darwin and working between North- west Cape in Western Australia and Brisbane in Queensland. This work should preferably be integrated into an overall programme for the Timor, Arafura, Java and Banda Seas by international agreement. A fully- equipped vessel, containing both biological and chemical laboratories, would be needed to do the work. GREAT BRITAIN By G. E. R. Deacon, Admiralty Research Laboratory, Teddington, Middlesex N. A. MacxrintosH and H. F. P. Herdman published a paper, “ Distri- bution of the Pack-ice in the Southern Ocean,’ Discovery Reports, Vol. 19, pp. 285-296, Cambridge, 1940, in which they give the mean position of the northern edge of the ice based on all the observations made by the Discovery Committee’s ships, whale-factories, and other expeditions. They discuss the advance and retreat of the northern boundary of the pack-ice, and give a rough idea of the latitude in which the ice-edge is likely to be found in any particular month. N. A. Mackintosh has published “ The Antarctic Convergence and the Distribution of Surface Temperatures in Antarctic Waters,” Dis- covery Reports, Vol. 23, pp. 177-212, Cambridge, 1946. He tabulates all the crossings of the Antarctic convergence by the Discovery Com- mittee’s ships and uses all the continuous thermograph records to construct charts of the surface isotherms in the Southern Ocean for each month. They give a more realistic picture of the temperature distribution than could be obtained by averaging the surface temperature observations made in each 1° or 5° square, and show how the isotherms crowd together near the Antarctic convergence. It is found that the great majority of the crossings of the convergence fall within 75 miles of the mean position. H. F. P. Herdman has published “‘ Soundings Taken During the Discovery Investigations, 1932-39,’ Discovery Reports, Vol. 25, pp. 39— 106, Cambridge, 1948. He gives a new bottom chart of the Ross Sea, questions the existence of a submarine connection between New Zealand and Macquarie Island, and gives new information about the bottom topography near the Balleny Islands. He gives a brief summary of a large number of profiles obtained in the neighbourhood of the South Shetland Islands. It is noted that the echoes are always weak in the neighbourhood of the Antarctic convergence ; two possible causes are mentioned: the mixing of the water masses in the boundary region, and the presence of a very soft deposit of diatom ooze. G. E. R. Deacon, in a paper on “ Water Circulation and Surface Boundaries in the Oceans,” Quarterly J. R. Met. Soc., Vol. 71, pp. 11-25, 1945, has emphasized the importance of the Antarctic convergence as a biogeographical boundary and has shown how the stratification of the bottom oozes in the boundary regions between red clay, globigerina ooze, diatom ooze, and glacial sediments can be used to obtain information about the interrelated decrease in the flow of the Antarctic surface and bottom currents since the Glacial Period. 146 THE INTERNATIONAL COMMITTEE ON OCEANOGRAPHY, SET UP BY THE COMBINED UNIONS OF BIOLOGICAL SCIENCES AND OF GEODESY AND GEOPHYSICS By Lieut.-Colonel R. B. SEYMOUR SEWELL, Secretary, the Zoological Laboratory, Cambridge, England EXCERPTS TAKEN FROM THE MINUTES OF THE MEETING HELD IN THE ROOMS OF THE ROYAL SOCIETY OF LONDON, BURLINGTON House, LONDON, ON 22ND AND 23RD May, 1947 Members— Appointed by the Unions— Dr. C. von Bonde, Department of Commerce and Industry, Central Street 216, Pretoria, South Africa. Dr. Charles Fish, Professor of Zoology, Rhode Island State College, Kingston, R.I., U.S.A. Professor B. Helland Hansen, Det. Geophysisk Institut, Bergen, Norway. Dr. Harald U. Sverdrup, Director, Scripps Institute of Oceano- graphy, La Jolla, U.S.A. Professor Hans Pettersson, Oceanografiske Institutet Stejberg- storget S., Goteborg, Sweden. Professor J. Proudman, F.R.S., The University, Liverpool, England. Professor Dr. H. Boschma (Convener), Rijksmuseum van Natuurlijke Historie, Leiden, Holland. Co-opted Members— Lieut.-Colonel R. B. Seymour Sewell, C.I.E., F.R.S., The Zoological Laboratory, Cambridge, England. Professor Louis Fage, Institut Oceanographique, 193, Rue Saint- Jacques, Paris, Ve. Professor W. J. Dakin, Department of Zoology, University of Sydney, Sydney, Australia. Dr. E. C. Bullard, F.R.S., Department of Geodesy and Geophysics, Cambridge. Members Present— Dr. H. Boschma (Convener). Professor Hans Pettersson, of Sweden. Professor Proudman, of Liverpool. Dr. R. B. Seymour Sewell, of Cambridge. The meeting was also attended by Professor F. J. M. Stratton, F.R.S., General Secretary of the Conseil International des Unions Scientifiques. Dr. H. Boschma was elected as Chairman of the Committee and Dr. R. B. Seymour Sewell was appointed Secretary. It was decided to consider the co-optation of additional members to the Committee— Dr. Ph. H. Kuenen, of Holland. Dr. Bullard, F.R.S., of Cambridge. Dr. Louis Fage, of the Musee d’Historie Naturelle, Paris. It was proposed that Dr. Dakin, of Sydney, Australia, should be co-opted. This was agreed to. 147 The Committee considered proposals put forward by Professor Hans Pettersson, which were as follows :— It is proposed that future investigations of the deep ocean bed by means of new technique, developed during the war years, shall be organized on an international scale in order to prevent overlapping of individual efforts and in order to concentrate the work on problems of outstanding importance. As problems of this nature, falling within the realm of geophysics, the following may be mentioned :— A. Deep coring in the deeper basins of the oceans and also across and near ridges like the Central Atlantic Ridge; also along lines converging towards active or recently extinct volcanoes, and towards atolls and areas where recent elevation or subsistence of the ocean-bed is suspected ; also along the continental slope of regions like the “ De Geer ’”’ line and near broken off mountain chains. Special attention should be given to coring along border lines between different kinds of sediments. B. Measurements of the thickness of the sediment by means of echo-sounding in the above localities, and also where former land connections are suspected. Especially needed are comparisons of the thickness of the sediment in the Atlantic Ocean as compared with the Pacific Ocean, which may supply evidence for or against Continental drifting. C. Measurements of the geothermal gradient in the basins and the deeps, especially where the rate of sedimentation may be expected to show very low values. D. Suggestions for the biological programme in deep-sea research— (1) Design of experimental apparatus (grabs, &c.) for the investi- gation of the bottom fauna. (2) The study of the invertebrate fauna in great depths. 3) The microfauna of the detritus layer. ) Metabolism in animals living at temperatures below zero. ) Quantative study of animal associations on the oceanic slopes. ) The fauna of the abyssal plains and deeps. ) ) ) — 4 5 6 7) Pelagic micro-organisms. 8) Ecology of the foraminifera. The nutrition of deep-sea organisms. 9 It is recommended that work on similar lines to the above should be undertaken by any oceanographic institute that may be founded in the future. The Committee considered a proposal put forward by Dr. R. B. Seymour Sewell for the foundation of an Institute of Oceanography for the study of the Indian Ocean, which was as follows :— In the report of the Preparatory Commission (Natural Sciences Committee) of UNESCO (vide Science and UNESCO: International Scientific Co-operation, page 33) it is recognized that ‘“‘ Those carrying out work for the International Council for the Exploration of the Sea should be associated with UNESCO as well as with FAO,” and they further recognized that Asiatic waters have never been covered. It was to remedy this great gap in our knowledge that at the meeting of the Committee on Oceanography and Fisheries of the British Commonwealth Scientific Conference, held at the Royal Society’s Rooms in June-July, 1946, I suggested the formation of an Institute of Oceanography for the Indian Ocean, and the Committee passed the following resolution :— “The Specialist Committee urges on the Governments of the countries bordering the Indian Ocean the desirability of close co-operation in studying the oceanography of that ocean. It suggests that such co-operation might be greatly facilitated by the establishment of an Institute of Oceanography in a suitable location, under the joint control and support of the Governments concerned.” (Unfortunately at the present moment certain of those Governments are in a State of flux, notably India and the Dutch East Indies.) By the recommendations of the Sub-Commission on Natural Sciences of the General Conference (1946) of UNESCO, the Secretariat is instructed (in para. 10, (i) ) “ to explore the possibility of the foundation of new international laboratories,’’ one of which is specifically mentioned—namely, (h) Oceanography and Fisheries of the Indian Ocean. 148 There is an enormous area of the Indian Ocean, especially the region to the south of the Equator to about lat. 40° S., of which we know practically nothing ; and the investigation of this region is highly desirable from the point of view of pure scientific research ; but perhaps the greatest claim for the support of such a project comes from the very intimate relationship that exists between oceanography and fisheries. In the publication ‘“‘ Science and UNESCO: International Co- operation ’’ (page 54) it is noted that of the four basic needs for the non-industrial countries, such as India, which the Economic and Social Council will be taking into consideration, the first is ‘‘ Increased production of food per man-power per day,’ and this is one of the prime concerns of FAO. Around the Indian Ocean a number of Governments have realized that in the present state of the world’s and of local food supplies it is essential that the fisheries should be improved and the methods of fishing be brought up to date and modernized. In order to ensure that this increased exploitation of the fisheries will not be carried on in an unscientific and harmful manner India has recently adopted a scheme for the establishment of a Central Fishery Research Institute with Fishery Research Laboratories on each coast, east and west. In addition to India, South Africa, the Islands of the Indian Ocean (Mauritius and Seychelles), Ceylon, and Malaya all have their Director of Fisheries and are carrying out research into their own local problems. In each of these areas a certain amount of pure oceanographic, as well as fishery, observations will of necessity be made, but in order to co-ordinate and correlate the work of these isolated fishery researches it is essential that there should be an Oceanographic Research Institute that would carry out researches in those areas that lie beyond the range of the local fishery research vessels. In this way we should be doing something to co-ordinate scientific knowledge and economic development. The committee considered proposals submitted by Dr. C. von Bonde, of South Africa, which were as follows :— It is difficult to formulate plans for discussion at the proposed meeting, but the following matters appear to be of importance to our work in South African waters :— (a) Practical work at sea is being held up at the present moment owing to the severe shortage of oceanographic instruments, deep-sea thermometers, and glassware for chemical analyses of sea-water. It is suggested that the International Council for the Exploration of the Sea in Copenhagen be requested to arrange for the immediate manufacture and means of distribution of such apparatus. (6) Methods of chemical analyses of sea-water should be standardized and printed in English, French, and German, and such publications should be available to marine laboratories throughout the world. (c) Anything that can be done to standardize oceanographic routine practice at sea would be an advantage. (d) Co-operative work between different marine laboratories as a means of collecting simultaneous observations at sea on specific problems through- out the oceans of the world should be encouraged, but particular emphasis should be made in regard to problems affecting immediate increases of fish products, having regard to the world shortage of food proteins and fats. I wish to suggest that a member of the International Council for the Exploration of the Sea, Copenhagen, Denmark, be also co-opted. Dr. Boschma submitted a series of proposals that had been sent to him by Dr. Kuenen. Dr. Kuenen’s proposals were as follows :— 1. Sedimentation in shallow seas, especially inland seas and shelf areas. These form the closest analogy to fossil sedimentation basins, in which most ancient sedimentary rocks were deposited. So far more attention has been given to deep- water deposits, but from the geologist’s point of view the systematic investigation of an inland sea is of at least equal interest: nature and distribution of the sedi- ments, wave and current action, organic content, &c. 2. The morphology of the Atlantic continental slope of Europe especially to ascertain faults, submarine canyons, &c.('). 3. Dredging to carry forward the investigations of Bougart’s tracts of sub- merged beach conglomerates at depths of 50 to 400 metres on the continental slope. 4. If Pettersson’s programme is carried out, his results will be of outstanding importance in formulating a programme for further work(?). 5. Geophysical investigation of the continental slope and deep-sea floor. 149 6. Under-water photography as developed in the U.S.A. during the war. If the technique could be applied to greater depths, that would be of outstanding poe eee Current and silt measurements close to the bottom under varying circum- Sree especially during rough weather and along breaks in slope. This would teach us more of the transport of sediment and the existence of new-depositional environments. 8. Chemistry of sea-water, especially the problem of solution and precipitation of lime (bottom water, surface layer). 9. Chemical analyses of sediments, both of bulk samples and individual samples, for geochemical investigations. 10. Radioactive age determination of log samples. 11. The influence of organisms on the deposition of fine particles. 12. The compilation of a new world chart. Addenda (1) Sounding of the European continental slope will require the co-operation of hydrographic surveys. An outstanding problem is to carry the investigation of a few submarine canyons right out to the deep-sea floor to ascertain whether they end in a “‘ delta’ or otherwise. Position finding by radar might solve the problem of locating the position of soundings. (2) Many thousands of samples will have to be taken from the cores and examined regarding mineralogical, radio-active, chemical and physical properties. Professor Hans Pettersson urged the very great importance of inter- national co-operation, especially in deep oceanic work ; he emphasized that the determination of the age of cores by means of radio-active measurement can only be done in deep-sea sediments. Professor Proudman called the attention of the Committee to the oceanographic investigations that could be undertaken by the meteoro- logical observation vessels and the necessity for the co-operation of the International Association (of Physical Oceanographers) and_ their collaboration with the International Committee on Oceanography. Such vessels would provide opportunities for continuous observations in more or less fixed positions. The British vessels would probably be able to carry out observations on the surface water, and possibly each country concerned in the scheme would organize certain researches for its own vessels. The Committee discussed the possibility of the re-establishment of the Oceanographic Institute at Monaco as an operating Oceanographical Laboratory. Dr. Boschma submitted to the Committee a report by Dr. Margaretha Brongersma-Sanders, of Leiden, Holland, on the occurrence and causation of mortality in fish on the coast of South-west Africa (particularly Walvis Bay) associated with the presence of “red water,’ and urging the desirability of carrying out research into certain phenomena in this region. A precis of the report follows :— In some of the bays on the coast of South-west Africa (especially Walvis Bay) and sometimes in the neighbouring open sea there is a periodic mass-mortality of fish, which always occurs in the southern summer (December). In the same area there is a peculiar bottom sediment, characterized by a high organic content, great quantities of H,S. gas and a nearly complete absence of living organisms, other than anzrobic bacteria; in this deposit are numerous fish remains and a very high percentage of the skeletons of diatoms. This azoic area extends from Cape Cross to south of Conception Bay (lat. 21° 20’—-24° 30'S.) and from near the coast- line out to about the 77 fathom line, a width of about 25-30 miles... The azoic area is separated from the shore by a coastal belt in which the bottom is fine grey sand and there is an absence of H,S. The active cause of the mortality i is by many attributed to the H,S gas, , but: the origin of this gas is in dispute. It may be either (1) carried down as;sulphur com- pounds from the land by rivers, or (2) due to the reduction of sulphates in the sediment by anerobic bacteria. 150 Dr. Brongersma-Sanders puts forward a third suggestion—namely, that the mortality is attributed to the presence of ‘‘ red-water,’’ caused by the presence of large numbers of Dinoflagellates, associated with up-welling water. Similar phenomena of up-welling water, large numbers of Dinoflagellates, and fish-mortality occur in other regions (e.g., California, Peru—Chile, and perhaps the South coast of Arabia), and a similar area seems to have existed in past geological times in the northern Caucasus. The Walvis Bay azoic sediment shows a remarkable resemblance to certain bituminous fish-shales. The action of the Dinoflagellates may be attributed to either (1) the production of a toxin or (2) asphyxiation by the mechanical clogging of the gills. In California there seems to be a close connection between the total number of Dinoflagellates and a toxicity of the mussels, the shell-fish themselves being resistant to large quantities of the poison that is probably produced by the Dinoflagellates. The following studies should be carried out :— A. A quantitative and qualitative study of the plankton throughout the year What oceanographic peculiarities are associated with the occurrence of “red-water’’ ? What is the extent of the “red-water’”’ in different years, and does it coincide with the azoic area ? B. A study of the bottom sediment to determine its nature (Guttja or Sapro- pelium) ; the nature of the enclosed organic compounds; the presence of certain metals, such as Cu, Ni, Va, Mo, &c. Determination of the organic carbon and nitrogen from the top layer and at deeper levels of the sediment. Does the O,/H,.S boundary lie at the surface or at some distance below ? C. Is the fish mortality due to a toxin, related to the paralytic shell-fish toxin, that is produced by the living Dinoflagellates, and does paralytic poison- ing of man from eating mussels during the summer occur on the South- west African coast ? Professor Hans Pettersson suggested that UNESCO should be approached and be asked whether it would consider the appointment of an Assistant Secretary, who, working under the Secretary, would keep in touch with “ liaison ”’ representatives in all countries that are interested in oceanographic work and so keep the Committee informed regarding any oceanographical investigations that were being carried on or were contemplated in both the physico-chemical and biological branches, The following resolutions were passed :— 1. The International Committee on Oceanography have heard with very great interest Dr. Hans Pettersson’s account of the Swedish plan to study the deep ocean bed and its fauna, and of the possibility of a further extension and continuation of this work through co-operation between the Scandinavian Countries— Sweden, Norway, and Denmark. The Committee considers that such investigations are of the greatest value from the scientific point of view; and that they would benefit from international co-operation and should be organized on an international scale. 2. The International Committee on Oceanography noted with great interest the proposal (contained in para. 10 (fA), of the Digest of Directives, Sub-Commission on Natural Sciences, UNESCO General Conference, 1946) to explore the possibility of founding an Oceanographical and Fisheries Laboratory for the Indian Ocean. The Committee consider that the creation of an Institute of Oceanography for the Indian Ocean would be of the greatest value for the advancement of our scientific knowledge of this region. They also consider that such an Institute would probably lead to considerable economic advantages for all countries bordering on this ocean, and earnestly trust that means will be found for the establishment of such an institution. The Committee also hope that, if and when the constitution of such an institution is being considered, full advantage will be taken of the experience gained by the International Council for the Exploration of the Sea. 151 EXCERPTS TAKEN FROM THE MINUTES OF THE MEETING HELD IN OSLO, Norway, 19 AucGustT, 1948 Members present— Professor H. Boschma (Chairman). Professor Louis Fage. Professor J. Proudman. Dr. Harald U. Sverdrup. Lieut.-Colonel R. B. Seymour Sewell (Secretary). Visitors who attended the meeting— Drs jeoN} Carruthers: Mr. Jens Smed. Dr. Johan T. Ruud. Lieut.-Commander J. R. Lumby. Dr. F. S. Russell. Dr. N. A. Mackintosh. Dr. H. Blegvad. Captain C. D. Meaney. Dr. Helge Thomsen. Dr (Gy EMRe Deacon: Dr. J. D. H. Wiseman. Mr. John B. Hart. CONSIDERATION OF MATTERS ARISING OUT OF THE MINUTES OF PREVIOUS MEETING The Present Position of the Oceanographic Institute of Paris and its Oceanographic Laboratory at Monaco.—Professor Louis Fage explained the present position of the Institute. He pointed out that at the present time it is very difficult for physical oceanographers to find suitable laboratories in which to carry on their studies; there are much better facilities available to marine biologists. Professor Fage pointed out that there was before the Commission a proposal to set up an inter- national committee of experts in order to encourage the foundation of many more oceanographic stations all over the world, but he thought that existing stations should have a prior claim to help. He had discussed the present position of the Oceanographic Institute of Paris with Dr. Joseph Needham, the representative of UNESCO at the meeting of the International Union of Biological Sciences, and it was agreed that UNESCO ought to help. He therefore proposed that the Commission should transmit his report to the Conseil International des Unions Scientifiques and should recommend that UNESCO should be asked to give SER financially to the Oceanographic Institute at Monaco. This proposal was discussed, and it was unanimously agreed to support Professor Louis Fage’s proposal. It was decided that a letter should be sent to the Secretary of the International Association of Physical Oceanography to inquire whether that Association will support such a resolution, and if they agree to do so, that the resolution should be sent to UNESCO through the Conseil International des Unions Scientifiques. 152 The Action to be Taken Regarding the Appointment by the International Council for the Exploration of the Sea of a Representative on the Com- maission.—It was proposed and carried that the Secretary should be instructed to write to the International Council for the Exploration of the Sea and ask them to appoint a representative. Consideration of a Note, Drawn Up and Circulated to All Members of the Commission, on the Need for Establishing Marine Biological and Oceanographic Laboratories in Various Parts of the World.—The Secretary drew attention to the fact that FAO have formulated a comprehensive scheme by which the oceans and seas are divided into seven regions, in each of which it is proposed to establish an International Council on the lines of the International Council for the Exploration of the Sea, and that steps had already been taken to set up such a council for South-east Asia. The Secretary also informed the Commission that a proposal for the establishment of a marine biological and oceanographic laboratory in the Kei Islands had been brought before the International Union of Biological Sciences at their meeting in 1947, and that a Com- mittee, of which he was Chairman, had been appointed by the Union to consider this project. This Committee had reported that, owing to lack of necessary facilities, it was considered impracticable to set up a permanent laboratory in these islands, but that if a parent laboratory could be established somewhere in the South-east Asian area it might be possible to have a subsidiary temporary laboratory in the Kei Islands. Professor H. Boschma informed the Commission of the very great opportunities that exist in the area round the Kei Islands for the study of the deep-sea fauna, which here thrives in as shallow a depth as 200-400 metres. Professor Louis Fage urged that a resolution should be sent to UNESCO, as suggested in the Secretary’s note, urging the establishment of a marine biological and oceanographic laboratory in this area. He pointed out that the Food and Agricultural Organization at the | meeting of international representatives that had been convened in the Philippine Islands in February last had delegated the research in a number of different branches of study to different Scientists or Scientific Institutions located in widely separate localities, as, for example :— Hydrology to the Marine Laboratory at Batavia. Taxonomy and Systematics of Fish to Dr. S. L. Hora, the Director of the Zoological Survey of India, at Benares, India. Fish Migration to Dr. Herklots in Hong Kong. Fishery Technique was to be studied in the Philippine Islands. Such an arrangement he considered to be quite impracticable. Dr. Carruthers (Visitor) pointed out that one could only study the migrations of fish if one was in the same area as that in which the fish were present. Professor Louis Fage submitted the following resolution to the Commission :— “ That this Commission request UNESCO to approach the Food and Agriculture Organization and get an international conference summoned to discuss the necessity of establishing a marine biological and oceanographic station in each of the areas into which FAO proposes to subdivide the oceans, if no such laboratory already exists; and that representatives of those organizations that are interested in this branch of research, such as the Australian Council of Industrial and Scientific Research, the International Council for the Exploration of the Sea, &c., as well as representatives of the various laboratories in the different areas, should be invited to attend.” This resolution was carried unanimously. Consideration of a proposal submitted by Professor Romanovsky for the establishment of a “ Review of Oceanography ”’ :— Professor Louis Fage pointed out that a very similar proposal was being brought before the present meeting of the Association d’Oceano- graphie Physique by Dr. P. Green. By this proposal it was hoped that the Association d’Oceanographie Physique would resolve to establish an inclusive, periodical bibliography on physical oceanography and its border fields, preferably in co-ordination and combination with a biblio- graphy on marine biology. Sucha publication would cover most of the ground suggested by Professor Romanovsky, the main exception being the absence of special articles. Dr. F. S. Russell (Visitor) suggested that there were already in existence a number of journals in which such special articles could be published, and Dr. Blegvad (Visitor) pointed out that the International Council for the Exploration of the Sea in their publications gave a bibliography of a number of papers on marine biology and oceanography. Dr. Sverdrup considered that it would be of great value to investigate the problem of how world-wide literature on this branch of science could be got together, and he suggested the appointment of a committee to go into the matter. Professor Proudman suggested that the Commission should nominate several biologists and should ask the Council of the Association d’Oceanographie Physique to include these biologists in the committee that is to be appointed by the association to consider the proposal of Dr. Green. This proposal was adopted, and the following Biologists were nominated by the Commission :— Professor Louis Fage, Lieut.-Commander Lumby, and Dr. Ruud. It was resolved that the Commission could not support Professor Romanovsky’s proposal. OCEANOGRAPHIC ACTIVITIES OF THE U.S. COAST AND GEODETIC SURVEY 1939-1949 By Rear Admiral L. O. CoLBert, Director, Washington, D.C. THE oceanographic activities of the Coast and Geodetic Survey in the Pacific area, between the years 1939 and 1949, embraced three fields— hydrographic surveying, tide and current work, and nautical charting. 154 HyDROGRAPHIC SURVEYING The principal hydrographic operations were carried on in Alaskan waters. A total of approximately 244,000 miles of sounding lines were run covering an area of 154,000 square miles. Prior to World War II Coast and Geodetic Survey vessels in Alaska had completed charting a large percentage of the waters of south-eastern Alaska and had made good progress in charting south-western Alaska. With the outbreak of the war the waters in the vicinity of the Aleutian Islands became strategically important, and the bulk of the hydrographic work was concentrated there. Since the close of the war these surveys have been extended, and hydrography has now been completed in an area extending 60 miles on either side of the island chain from longitude 170° E. to the general vicinity of Kiska Island. A comprehensive survey has been initiated in the Bristol Bay area and along the Arctic coast of Alaska, where little is known of the depths of water, the character of the ocean bottom, or the behaviour of tides and currents. The programme of deep-sea sounding-lines across the Gulf of Alaska by Coast and Geodetic Survey vessels while en voute to and from their west coast bases was interrupted during the war years. Work was resumed in 1945, and has since been extended into the north Pacific Ocean. This extensive project has added greatly to our oceanographic knowledge of the area. Many unknown submarine features have been discovered and more complete data obtained on known features, notably the Aleutian Trench. In 1947 an uncharted seamount was found in latitude 51° N., longitude 143° W., which rose to a depth of 460 fathoms from surrounding depths of over 2,000 fathoms. Off the Pacific coast of the United States hydrographic operations were practically suspended during the war years. Since 1939 approxi- mately 33,000 miles of sounding-lines were run covering an area of 6,500 square miles. Hydrographic surveys were started in the Midway Island area in 1941, but were abandoned after the attack on the Hawaiian Islands. In the course of the hydrographic operations numerous observations were made for the determination of temperature and salinity of sea- water. In addition, magnetic stations were occupied and the data obtained have contributed to the maintenance of isogonic charts of the ocean areas. Several notable developments in hydrographic techniques made during the past ten years will have significant effects on the collection of oceanographic data in the Pacific and elsewhere. Graphic recording fathometers were adopted by the Bureau in 1940 as standard equipment for hydrographic survey parties. This equipment greatly expedited operations in shoal waters. Greater accuracy in echo soundings are being achieved by improvements in the time-measuring device and in operational techniques. Shoran, a wartime electronic development for pin-point bombing, has been adapted by the Coast and Geodetic Survey for locating a ship’s position in hydrographic surveying at distances of 50 to 75 miles from shore. The first surveys using this method were made in the western Aleutians in 1945, and has since been extended to other areas. Shoran has completely replaced the former radio acoustic ranging method. Another electronic method, known as the electronic position indicator, 155 has been developed by the Survey to extend offshore hydrographic surveys beyond the limits of Shoran. This equipment was tested under service conditions in 1947, and distances up to 225 miles from shore have been measured. The new distance-measuring devices will make possible more rapid extension of offshore surveys and more accurate oceanographic investi- gations in the regions of the continental shelves and beyond. TIDE AND CURRENT WORK The programme of collecting, analysing, and publishing tide and current data for the Pacific area was considerably expanded since 1939. Two factors contributed to this stepped-up programme. The war in the western Pacific being largely amphibious in nature, our armed forces required information on tides and currents for their over-all planning. As a result, numerous tide gauges were established and current surveys conducted in strategic areas, and a large number of special predictions were prepared. The accumulation of tidal observations has been analysed harmonically and constants determined for 144 places in the Pacific Ocean. Much of this material has now been incorporated into the tide and current tables. Special tide and current tables are still being published for the Philippine Islands as well as for Japan and China. For 1949 the tables, together with the regular tide tables for the Pacific and Indian Oceans, contain daily tide predictions for 104 places and tidal differences for about 2,500 places, as compared with 49 and 1,800 respectively for 1939. Daily current predictions have been added for thirteen places. The second factor responsible for the increase in the tidal work of the Bureau has been the programme of co-operation with the Latin American countries, inaugurated in 1941, and with other Government agencies in the western Pacific. The Bureau is now maintaining forty- eight automatic tide gauges in the Pacific. The accumulation of tidal data will not only provide much-needed original information for the prediction of tides, but will contribute greatly to the development of tidal knowledge in the Pacific. A comprehensive current survey of Puget Sound, using the newly- developed radio current meter, furnished the basic material for two recently published tidal current charts for the northern and southern parts of the Sound. A number of current surveys were made in San Francisco Bay and in Alaskan waters. A revised edition of Tidal Current Charts, San Francisco Bay, and a pamphlet based on five months of current observations in San Pedro Channel, California, were issued. Comprehensive current surveys of the various passes along the Aleutian Island chain and of the passages through the San Juan Archipelago in Washington are planned. Since 1943 the Coast and Geodetic Survey has been systematically making observations for temperature and density of sea-water at most of its tide stations. Publications giving the results of these observations are revised every two years. Studies are under way for the development. of a general warning system for seismic sea waves. Three steps have thus far been taken : a chart has been published showing the time required for a seismic sea wave to reach Honolulu from an earthquake epicentre in the Pacific ; a local sea-wave detector, which utilizes the arrival of the first part of 156 the seismic sea wave for alerting the area, was developed and placed in operation at Honolulu and at Hilo; and a chronological file of seismic sea-wave data has been set up. In addition to these steps, the warning system, when fully developed, will involve rapid co-operation on the part of seismological observatories, tide stations, and communication networks. NAUTICAL CHARTS The experimental chart, No. 51014, which the Coast and Geodetic Survey published in 1939 for the southern California area has important significance in oceanographic studies. This type of chart is characterized by many depth curves which bring to light submarine features not readily discernible on the conventional type of chart where many soundings are shown, but only few depth curves. Practically all of the Pacific coast charts follow this new pattern and it is being applied to the charts in other areas where information is available for the accurate delineation of the submarine topography. PAPERS PREPARED FOR PACIFIC SCIENCE CONGRESS The two following papers were prepared for presentation :— Tidal Investigations in the Pacific, by E. C. McKay. A Seismic Sea Wave Warning System for the Pacific, by W. B. Zerbe. UNERED re SEADES DIVISION ZOF OCEANOGRAPHY >) Tir HYDROGRAPHIC OFFICE, UNITED STATES NAVY THE following excerpts are taken from the annual report of the Hydrographic Office :— Collection and Dissemination of Oceanographic Data The oceanographic programme continued at an increased rate the implementation of the more or less routine tasks included in the programme. These tasks, in part, include the collection and maintenance of the files of basic oceanographic data; compilation, analyses, and preparation of this data for inclusion in reports, manuals, and publications; standardization of the methods for observation and reporting of oceano- graphic information by both governmental and non-governmental] agencies ; preparation of reports in answer to requests for oceanographic informetion from military and non-military activities; participation, through procurement of equipment and personnel, in Navy-sponsored expeditions and representation on numerous committees and panels concerned with oceanography and related sciences. Numerous new programmes were initiated. One such programme is concerned with oceanography and allied studies in high latitudes. Studies relating to physical characteristics, distribution, and movement of sea ice were started and are continuing. The development of new specialized equipment, rather than the modification of present equip- ment, was instigated ; codes and reporting forms to assist in standard- ization of methods of recording ice data were prepared and issued, and such related items as the preparation of an ice glossary, in several languages, were initiated. 157 Another programme of interest was the standardization of hydro- graphic and oceanographic observations aboard naval vessels. This programme has already resulted in considerable benefit to the Navy, this benefit resulting not only from more accurate data, but also from the greatly increased quantities of information pertaining to sonic soundings, horizontal and vertical sea temperature distribution, sea and swell, sea ice, aids and hazards to navigation, and harbour and port facilities. Library Facilities.—The library has increased its collection of scientific and technical works, especially those pertaining to the field of oceano- graphy and allied sciences. The library at present consists of over fifteen thousand publications, pamphlets, and periodicals on the subjects. of geography, hydrography, oceanography, navigation, physics, and chemistry. In February, 1948, all branch Hydrographic Offices were equipped with modern “ reference libraries ’’ of the latest books and publications on navigation and related subjects, as a means of improving the services of the branch Offices to the Navy, the Merchant Marine, and the general public. Oceanographic Surveys.—The first requisite for an understanding of the various oceanographic phenomena, such as currents, sea and swell, and temperature, salinity, and density distribution, is adequate geo- graphic and seasonal records related to these phenomena. This necessitates a continuous programme of observation which must, of necessity, be conducted at sea. Every source of basic data must be exploited. As the Office did not have its own laboratory and ships for conducting these observations, other activities, both governmental and non-governmental, domestic and foreign, were called upon to supply these data. The results of these programmes, in part for the collection and reporting of basic oceanographic data are indicated in the table below. Quantity Source of Data. Type of Data. (Approximate). Surface vessels of the U.S. Fleet .. | Bathythermograph records | 4,000 records. Submarines Me ag .. | Bathythermograph records 1,700 records. Merchant Marine Bic .. | Surface current, tempera- | 40,000 records. ture, and sea and swell records Vessels of the U.S. Fleet .. | Sea and swell observations 1,500 records. The records listed in the above table by no means represent the total of the data received. Arrangements were made for oceanographic technicians to accompany Navy-sponsored expeditions to the Arctic and other areas of strategic importance. The Hydrographic Office observers sent to the Antarctic in 1947-48 were trained in collecting oceanographic data. These technicians carred out a detailed and compre- hensive programme of observations, and their results are embodied in reports submitted to this Office. In addition, privately-operated research vessels, both domestic and foreign, observed and reported many diversified types of oceanographic data. 158 Development and Procurement of Equipment.—tin order that the basic oceanographic data may be collected in a most usable form and in the most expeditious manner, specialized oceanographic equipment is necessary. The Office played an active role in the development of new types of such equipment and in the improvement of existing equipment. Also, a comprehensive list of equipment and supplies, with the possible source of procurement, was compiled and furnished to interested activities, Forty-three deep-sea reversing thermometers were received from Richter and Weise in Germany, and an order was placed for an additional seventy. The Woods Hole Oceanographic Institution completed their thermometer calibration chamber, the first of its kind in the United States, and all Hydrographic Office thermometers are now being calibrated. Some thermometers were received from Woods Hole Oceanographic Institution, after calibrated, and issued to United States Navy Electronics Laboratory for co-operative use. Various other types of sampling equipment, including bottom samplers, Nansen bottles, bathythermographs, and sample bottles were procured for use aboard naval vessels by the technicians. Two hydro- graphic winches of special design, incorporating hydraulic control and a constant tension device were ordered. A new type of stream-lined oceanographic sounding weight was designed and four were ordered. Considerable effort was expended in design, development, and pro- curement of equipment for use in the Arctic. Contracts were let for the manufacture of several pieces of this equipment, including a field kit for testing the mechanical properties of sea ice. Contracts with Oceanographic Laboratories.—Because of the present limited personnel and the lack of facilities required for observations and research it was impossible to conduct all of the projects within the Office. Consequently a portion of the funds available for the oceanographic work were used to support contracts at the Scripps Institution of Oceano- graphy, La Jolla, and the Woods Hole Oceanographic Institution, Woods Hole, Massachusetts. A considerable quantity of basic data was procured by these con- tractual agencies, both by personnel aboard their research vessels and by their technicians designated to accompany Navy-sponsored expeditions. Specifically, studies concerned with the hydrography of the North Atlantic, which includes bottom sediments, temperature, salinity and density distribution, and transparency measurements ; character- istics, distribution, and movement of sea ice ; fog forecasting techniques ; waste disposal at sea; Pacific Ocean biology and the deep scattering layer were received. A total of fifty technical reports was received from the contractors during the year. In addition to the observational programmes undertaken by the contractual agencies, the procurement of oceanographic data is imple- mented by their development and construction of equipment. During fiscal 1948 current meters, bottom-sampling devices, water-sampling devices, and continuous recording equipment for salinity, temperature, and depth measurements were among the items under development or construction. 159 The bathythermograph slides received from units of the Fleet and other governmental and privately-sponsored surveys are processed by the contractors. A total of over ten thousand processed bathythermo- graph records was received by the Office during the year. Compilation of Oceanographic Data.—Once the data has been received by the Office it must be processed so that it may be filed and be readily accessible for use during the preparation of charts, manuals, and reports. Some types of data, received in tabulated form, are filed without further processing. Other types of recorded information such as that on the sea and swell forms and the Special Observer’s Logs are punched into IBM cards for ease of filing and sorting. The bathythermograph records, which number approximately two hundred thousand, are photographic copies of the originals. During fiscal 1948 the entire collection of bathythermographs were refiled by global quadrant, one degree quadrangle and by month. Bibliographic Files—One important phase of the oceanographic compilation programme is the acquisition and maintenance of a biblio- graphic file. This file includes not only the card index, cross referenced to subject, author, and area, but also, whenever possible, copies of the technical papers and reports, either published or manuscript. Oceanographic Publications—The end products of the survey and compilation programmes are the publications. As the types of data concerned with the oceans cover many basic fields of science, the resulting publications are also varied, both in type and subject. Examples of these publications include current, sea, and swell and temperature atlases, sonar, bottom sediment, density and temperature charts; reports, for general or specific areas, relating to currents, sea, and swell, currents, sea ice, &c., and various other technical and popular studies relating to all phases of oceanography. Oceanographic Conferences.—As this Office is responsible for all oceano- graphic work conducted by the armed forces it is necessary that close liaison be maintained among all activities concerned. These activities, in part, include the Research and Development Board, the Bureaus and Offices of the Navy Department, the Army and the Air Forces. Also other governmental agencies, such as Fish and Wildlife Service, the Coast Guard, and non-governmental activities such as the various oceanographic laboratories and universities, must be frequently consulted. The most practicable way to maintain this laison and co-operation is through conferences of interested personnel. During fiscal 1948 personnel from this Office attended a total of 118 conferences which met in Washington, Baltimore, Seattle, San Francisco, Woods Hole, and other localities on oceanographic matters. Liaison on Oceanographic Matter —Through co-operation with other agencies, both governmental and non-governmental, domestic and foreign, the amount of oceanographic data received was considerably increased. Reporting forms were supplied to the Swedish research vessel the ‘“‘ Albatross’’; close liaison was maintained between the Fish and Wildlife Service and the Division resulting in a mutual exchange of data ; tidal information was procured from the Coast and Geodetic Survey. Considerable information was obtained from oceanographic laboratories and activities in foreign countries. 160 Prt ALAN HANCOCK FOUNDATION FOR: SCIENTIFIC RESEARCH By IRENE McCuLtock, University of Southern California, Los Angeles, California Art the Allan Hancock Foundation for Scientific Research at the Uni- versity of Southern California, Los Angeles, California, most of the emphasis will continue to be placed on marine biological research in the fields of Invertebrate Zoology. Some oceanographic research under the direction of Dr. K. O. Emery and assistants will centre on the eleven partially closed basins off southern California in an attempt to find the mutual dependence of sea-water characteristics and diagenesis with the hope that knowledge of environ- ments existing at present in the basins will lead to better understanding of the conditions of petroleum accumulations in the Los Angeles oil fields. A thorough core sampling programme of the various deep basins on the Continental Shelf off southern California is planned in connection with oceanographic work. New coring apparatus is in process of con- struction and should be available for this work by the end of 1948. Along with extensive programmes in the field of marine invertebrate research, the limited research programme in oceanography and sedimenta- tion studies, much time and thought will be placed on the development of equipment, directly connected with the ship and otherwise, the possibilities of television from ocean bottom to the ship, and the use of a benthoscope for direct observation of ocean bottoms around the islands off southern California. Some time will be spent on developing more effective nets for obtaining animal populations, including fish. THE PACIFIC OCEANIC BIOLOGY PROJECT By CHARLES J. FisH, Woods Hole Oceanographic Institution EXCEPT in Japanese home waters, Palau and Bikini, there has been relatively little research on the biology of pelagic ocean populations of the central and western North Pacific. There remains a dearth of data on the interaction of biological processes and the environmental factors involved in. their production, distribution and fluctuations, particularly in tropical areas. Such major problems, involving multiple controlling factors, require the combined services of a group of experienced investigators in a carefully. co-ordinated long-range programme. Following the termination of the war a Pacific Science Conference in Washington, on 6th to 8th June, 1946, recommended to the National Research Council the organization of a Pacific Science Surv ey. Oceanic biology was one of the subjects proposed and endorsed by the Conference. However, as recommended, oceanic biology problems in the central and western North Pacific “ .. . . should not be attacked before a thorough survey has been made of the information accumulated by our own agencies during the war, gathered by our allies or contained in captured Japanese documents. The first step toward approaching many problems should, therefore, be an examination and critical analysis of that information.”” It was considered especially important that Japanese data be reviewed in the light of recent developments in marine biology in other countries. 161 Q—Pac. Congress The first phase of the programme was instituted on Ist September, 1946, by the Woods Hole Oceanographic Institution with a grant from the Office of Naval Research, the designated objective being to assemble and analyse available data and thereafter to formulate a comprehensive field programme. Subjects specified for attention were— 14 (1) Character and distribution of plankton as related to features in physical and chemical oceanography and to the natural resources of the sea ; 2) Distribution and growth rates of reef-building corals ; 3) € ) ) Causes and occurrence of phosphorescent waters ; 4) Regional distribution and biology of fouling organisms ; ) ( ( ( (9 Character and prevalence of sound producing marine animals ; and (6) Poisonous or otherwise dangerous marine animals. A staff of six marine biologists and technical assistants first compiled a 5 Isosvareiie card index, with abstracts, of some ten thousand titles. A set of 4,098 Japanese nautical and oceanographic charts were next catalogued and titles translated. To further facilitate the use of Japanese material a glossary of Japanese hydrographic terms (approxi- mately four thousand words) and a comprehensive Japanese ocean- ographic dictionary have been prepared by Rodney Notom1. Analysis of data and preparation of reports on the assigned subjects are now well advanced. Five scientific reports have so far been completed :— (1) “Sonic Fishes of the Pacific.”’ by Marie P. Fish. Available data on sonic members of forty-two families of teleosts are presented with an extensive bibliography of literature on the subject. The seasonal and regional distribution of subsurface noises attributable to fishes have been charted from records in Submarine War Patrol reports. * Practical Aspects of Coral Reef Growth,” by Gordon A. Riley. A consideration of the present status of knowledge on Pacific reef growth and the environmental:factors involved, with a classified bibliography of pertinent publications. (3) “ Phytoplankton of the Western North Pacific,” by Gordon A. Riley and Ruth von Arx. Quantitative distribution. of Tamtos and certain of its environmental factors, including surface temperature, transparency, and the surface concentra- tions of phosphate, nitrate, nitrite, and silicate. The report is based largely on Japanese data which have been averaged by five- degree squares over periods of three months “for charting purposes. : (4) “ Fouling in the Western Pacific,” by Louis W. Hutchins... The area treated in this report is somewhat larger than in others of the series, fo permit incorporation of important data on the Hawaiian and Solomons— New Hebrides regions. Much of the information has been derived from a study of unpublished results of Navy-sponsored investigations and a large file, of data on ship, net,’and mine fouling acquired in the course of war-time operations. = bo wee 162 (5) “ Poisonous and Otherwise Dangerous Marine Animals of the Western Pacific,” by Charles J. Fish and Mary C. Cobb. A review of inedible, venomous or ferocious species of coelen- terates, molluscs, echinoderms, elasmobranchs, teleosts, and reptiles, based on published records and unpublished military documents. The following reports are in preparation :— (6) “ Bioluminescence in the Western North Pacific,” by Charles J. Fish. Regional and seasonal occurrence and the biology of the organisms involved. (7) “Sonic Marine Mammals of the Pacific,’ by Marie P. Fish. Existing information on the production of subsurface noise by mammals, the character of the sounds produced, and distribution records charted from Submarine War Patrol reports. (8) “ Zooplanktor of the Western North Pacific,’ by Charles J. Fish. Quantitative and qualitative analysis of available data on zooplankton correlated with environmental factors. To this end the methods of presenting the quantitative distributional data are being made as nearly uniform as possible with those - used in the report on phytoplankton. As originally planned, the comprehensive biological oceanography field programme, closely correlated with physical oceanography and high seas fishery research programmes now under development, would begin upon completion of the present studies. It is now evident, however, that before any major expansion in this field can take place new personnel must be trained. Provision is therefore being made for the training of a limited number of carefully selected graduate students for basic research in biological oceanography. 163 REVIEWS OF PACIFIC OCEANOGRAPHY REPORT ON THE OCEANOGRAPHIC LABORATORIES OF THE UNIVERSITY OF WASHINGTON By Tuomas G. THompson, University of Washington THE Oceanographic Laboratories of the University of Washington comprise the main laboratories situated on the campus of the University in Seattle and the field laboratories near the town of Friday Harbour on San Juan Island in Washington Sound. The laboratories in Seattle are housed in a three-storied brick building, funds for the construction and equipment of which were provided by the Rockefeller Foundation in 1930, and are well equipped for research in the various branches of oceanography. A circulating sea-water system is maintained at a temperature of 9° c., the average temperature of the waters of Puget Sound. The Friday Harbour laboratories are situated on a 480 acre tract with about two miles of shore-line. There are about a dozen buildings in the area, half of which are one-storied buildings of hollow tile con- struction and well equipped with all modern laboratory facilities. At the present time ten cottages with housekeeping conveniences are under construction for use of scientists and their families throughout the year. Much of the activities of the field laboratories centre around the summer quarter, when about one hundred persons are in residence. This number includes members of the staff, advanced investigators from a number of institutions, and graduate students, and also members of families. Tents are used for living quarters in the summer, and a central building serves as a mess hall. . The professorial staff consists of thirteen persons, two of whom devote full time to the work of the laboratories, one being the resident scientist at Friday Harbour. The other eleven members, including the director, are also affilated with one of the following departments : botany, chemistry, fisheries, geology, meteorology, microbiology, physics, or zoology. ‘The research interests of the staff and their graduate students centre around various problems in oceanography as related to their several specialties in the fundamental sciences. With the entry of the United States into World War II many of the staff were called into service or to other war duties. The Seattle labora- tories were taken over by the United States Navy, and the Friday Harbour laboratories were changed to a training school for the United States Coast Guard. The research vessel, “ Catalyst,’ which had been especially constructed for oceanographic work from funds granted in 1932 by the Rockefeller Foundation, was converted to a patrol vessel for use in Alaskan waters by the Coast Guard. After the war it was two years before the laboratories began to operate again to capacity. An Act of the United States Congress provided for the replacement of the research vessel, but currently two small vessels are charted, the plans for the research vessel still beg only on paper. 164 An oceanographic survey of Puget Sound, Washington Sound, and the Strait of Juan de Fuca is being conducted under the supervision of . Dr. Clifford A. Barnes, Associate Professor of Oceanography. This survey is a continuation of a series of long-range studies of the inland waters of the State of Washington and the coastal system. The objectives of this survey are to obtain a rigorous picture of the circulation within the Strait of Juan de. Fuca and Puget Sound and the exchange of these waters with contiguous water masses, including the open ocean; to assess the effects on the system of external influences such as tides, meteorological conditions, and river run off; and, where possible, to interpret the internal conditions, including the physical, chemical, and - biological regimes in the light of the overall physical oceanography. Drs. Alfred C. Redfield and William L. Ford, of the Woods Hole Oceano- graphic Institution, participated actively during the summer of 1948 m the survey. Research effort has been largely concentrated on obtaiming three- dimensional circulation patterns using the Salinity-Temperature-Depth Recorder (S-T-D). This device, developed at Woods Hole, will con- tinuously record the temperature of the sea-water and depth of sub- mersion of the sensitive element when towed or lowered from a ship. Although the reliability of the measurements is somewhat less than obtained from normal water-bottle techniques it is adequate to establish local gross circulation patterns and to define temporal changes that could not be readily observed by other means. The salinity of local waters varies from about 34°/,, near the bottom of the Strait of Juan de Fuca to near zero in the upper layers off mouths of rivers and provides a most useful index for determining the limits and tracing the movement of local water masses. Two fisherman type craft of 50 ft. and 55 ft. in length, operating out of the laboratories at Seattle and Friday Harbour, have been used for field-work. Continuous surface records have been made for approxi- mately 4,000 miles cruismg on seventy-eight trips, and in excess of one thousand lowerings have been made for vertical structure. Surface circulation patterns for the period July to September have been charted for flood and ebb tides in Washington Sound between the Straits of Juan de Fuca and Georgia and in the immediately adjacent waters of these Straits. An insight has been obtained of vertical structure and processes in this primary mixing zone of Fraser River effluent with ocean water. During September the area of investigation was extended sea- ward in the Strait of Juan de Fuca to within 30 miles of the open Pacific, and also to the head of Puget Sound. During the period October to December investigations were largely confined to the Puget Sound - Hood Canal system with numerous measurements being made in the entrance to Puget Sound, Admiralty Inlet, a critical constriction and mixing zone which restricts water exchange with the open Strait. The local circulation pattern is characterized by an incoming supply of relatively dense saline water upwelled from moderate depths of the Pacific entering the coastal system on the bottom of the Strait of Juan de Fuca and by a surface current of relatively fresh water from riyer run-off and precipitation flowing seaward on the surface. Wind and oscillating tidal effects are superimposed on the circulatory system to accelerate mixing and vary the net water exchange. Prime mixing zones normally occur at or near vertical or lateral constrictions in the 165 channels, mixed water flowing seaward superficially on the ebb and landward at depth on the flood. The irregular nature of the submarine topography, and effect of earth’s rotation, act on the moving water masses to give apparently anomalous density distribution and com- plicated flow patterns in which currents of different strata vary in both magnitude and direction. Model studies of critical areas are being initiated to supplement field observations. Although prototype conditions cannot be exactly scaled in any practical model it is expected that these studies will give a continuity and a flexibility not readily obtained in the field. Dr. C. L. Utterback, Professor of Physics, has been concerned with the radium analysis of sea-water, bottom samples, and organic material. He is extending his studies to include uranium and possibly thorium. The extensive radium analyses which have been made by him and other investigators and some very meagre data from questionable uranium analyses indicate a considerable departure from, radioactive equilibria. Thus the amount of radium in sea-water, 0-8 x 10~!® grams per gram of sample would be supported by 0-24~-° grams of uranium per gram of sample. The indications are that sea-water contains four to five times as much uranium as is necessary to maintain the radium balance. It is improbable, in the case of sediment washed by water, that radioactive equilibrium exists, but the unbalanced can be determined. The dis- tribution of radioactive material in marine plant and animal matter will probably give information as to the reason for the unexplained ratio of the radioactive products of disintegration. While the concentration of radium is such that rather accurate analyses have been made by the ionization method, the quantities of uranium present are extremely minute and new techniques are being developed for its determination. Considerable attention is being given to the nature of fogs, parti- iculanly sim’) the Seattle Yarea,Wiby. Di Bhi hss Churchrperotessormmon Meteorology. Serial ascents of a delicate low altitude meteorograph below a tethered balloon are made hourly during foggy conditions. The results show that in radiation fog the lapse rate ‘hankes from inver- sion to wet adiabatic as the fog thickness increases vertically. Plans are being initiated for the investigation of a number of characteristics ‘of the summer fogs which occur off the Washington coast. He is alsa planning to make extensive observations with the bathythermographs during the course of a year in the north-east Pacific to determine detailed thermal structure in the upper layers of ocean water and compute the heat loss and gain in opposite seasons. Dr. Rex J. Robinson, Professor of Chemistry, and the writer are engaged in studies on the distribution and methods of analysis for a number of the elements occurring in sea-water. At the present time refinements in the methods for the determination of potassium, strontium, and fluorides are receiving attention. A paper on the distribution of various nutrient salts, dissolved oxygen as well as the temperatures and salinities of the waters of Puget Sound, W ashing ton Sound, and the Strait of Juan de Fuca over a ten-year period is in preparation. A study is also in progress on the preferential adsorption of certain ions in sea-water in freshly forming ice crystals. Paired with this investigation is another dealing with a phase rule study on the deposition of the salts in sea-water by frigid concentration. Dr. Robinson is also occupied with a study of the determination and distribution of phosphorous in organic compounds dissolved in sea-water. 166 Present methods for the determination of plant pigments lack sensitivity and fail to give estimations of the different pigments present. A method using a small sample is being developed and can be standardized for comparison of results. The Tswett chromatographic method is being applied by Mr. Francis Richards. Small amounts of pigment are concentrated and compared with similarly adsorbed pigments of known amount. Preliminary results indicate that amounts of pigment too small for accurate colorimetric comparisons may be compared in this _way. A modification of the Harvey pigment standards, in which not only the concentration of the two coloured inorganic salts, but also their ratio o each other, is varied, offers a standard of greater versatility than the original Harvey standards. However, it appears that it will be better to report pigment values as percentage absorption in well- defined bands of the visible spectrum. This method is being developed for a chemical estimation of phytoplankton. Inv thes field of* biochemistry, Dr: Parl RK. Norns, Professor of Biochemistry, and his students have been engaged in several series of researches dealing with nutrition, vitamins, enzymes, and metabolism of marine organisms. Ready for publication are papers dealing with the purification and properties of the pepsin of halibut, albacore, yellow fin tuna, and blue fin tuna; the occurrence of arsenic in marine organisms ; the composition of marine alge and the seasonal occurrence ef laminarin in brown alge of the Puget Sound area, including the enzymetic hydrolysis of the carbohydrates of alge; and the nutritional requirements of young salmonoid fish. A long-range programme is being initiated by Dr. W. H. Blaser, Associate Professor of Botany, dealing with the distribution and characteristics of the alge of the Puget Sound and Washington Sound areas, together with considerable attention to physiological studies of some of the marine plants. Dr. Arthur W. Martin, Professor of Zoology, is.continuing his investigations on the circulatory phenomena of fishes. Blood volumes have been described in a number of species, great changes taking place in the blood volume during pregnancy of viviparous fishes. The characteristics of the hemoglobin of the young of viviparous fishes have been shown to conform to those of fetal mammals. The dynamics _of fluid exchange between the circulating blood and the tissue fluid are at present being investigated. Dr. Dixy Ray, Assistant Professor of Zoology, is examining early developmental processes in the coelenterates, the current form being the scyphistomae of Cyanea capillata. Her students are investigating hew mesozoans from the urimary tract of Polypus hongkongensis, the morphology of the tectibranch Phylla ply ysta taylort, and the classification of intertidal chitons. Dr. A. H. Whitely is pursuing work upon the mechanisms of energy transfer in the developing egg, with special emphasis upon the utilization of high-energy phosphate bonds. He is now in a position to follow the overturn of tagged phosphorus atoms in the metabolic cycle of the common invertebrate eggs. At the Friday Harbour laboratories continuous meteorological and tidal records, generally obtained by mechanically recording devices, are under the supervision of Dr. Emery S. Swan, Assistant Professor of Oceanography and Resident Scientist, together with quantitative studies of the seasonal variation of the temperature, salinity, and various 167 % nutrient salts of the sea-water near the laboratories. A study of -the shell secreting organs of the serpulid worms has just been completed and currently he is engaged in a statistical investigation of the relation- ship of growth indices to environmental factors for several species of clams. Dr. Erling J. Ordal, Associate Professor of Microbiology, is working on (1) the morphology and physiology of bacteria occurring on marine plants and animals, and (2) bacteria which cause disease in fishes, particu- larly salmonoid fishes. The School of Fisheries of the University of Washington has under construction on the Seattle campus a large fisheries laboratory, the site of which is immediately adjacent to that of the Oceanographic Laboratories. Thus located, considerable exchange of information is anticipated with Dr. Richard van. Cleve, the Acting Director, and Drawn, Delvacy nepiesentariyel or the School of jaisnoates on the oceanographic staff. The Library of the University of Washington is among the larger libraries of the United States. Through its inter-library loan service any volume or journal is readily obtainable. It also maintains a branch library at Friday Harbour which is housed in a special building. The publications of the Oceanographic Laboratories comprise the Publications in Oceanography in which longer or more detailed articles appear, and the Reprint Series. It is the policy of the laboratories to encourage as much as possible publication of the results of oceanographic research. in the standard scientific national journals. A large number of reprints of articles so appearing are purchased for the Reprint Series and used for inter-library exchange. SUMMARY OF DISCUSSION A short discussion followed, in which Dr. Deacon asked whether it was true that a commercial process was available for the extraction of potassium. from sea-water. Dr. Thomson replied that one project was under way in the United States, but that he had no information as yet as to actual results. OCEANOGRAPHIC CONTRIBUTIONS- OF MARINE BIOLOGICAL LABORATORIES ON THE PACIFIC COAST. OF NORTH AMERICA By Ropert C. MILrer, California Academy of Sciences, San Francisco THE investigation of the sea is a difficult and expensive undertaking. Only a few institutions can afford to maintain a research vessel of sufficient size to carry on work for weeks or months in the open sea. It is to be hoped that the number of such institutions may be increased and the funds available to them augmented. In the meantime, however, it is desirable to emphasize the role in marine inv estigations of seaside laboratories not equipped for full-scale oceanographic work. The marine biological laboratories, often housed in modest quarters and nearly always with inadequate funds, have made a large number of significant contributions to our knowledge of the sea, and several of them have in the course of time developed into laboratories devoted primarily to oceanographic research. 168 That has, in fact, been the history of all the oceanographic institutions on the Pacific Coast of North America. The Scripps Institution of Oceanography of the University of California began its history as the Scripps Institution for Biological Research. The University of Washing- ton Oceanographic Laboratories became successor in interest to the Puget Sound Biological Station. In 1911 the University of Southern California opened a small laboratory on a pier at Venice, California, where summer classes were carried on until it was destroyed by fire in 1921. A continuous thread of events can be traced from this modest beginning to the present extensive programme of the Hancock Foundation. It is not anticipated that all or most of the marine biological labora- tories will develop into oceanographic institutions. Some of them may ; but in any case all of them are in a position to contribute significantly to the sum total of our knowledge of the sea. It is the purpose of this paper briefly to review the nature and scope of such contributions by laboratories on the Pacific Coast of North America, other than those definitively engaged in oceanographic work. Historically the California Academy of Sciences, established in 1853, was the earliest centre of marine research on the Pacific Coast, and its Proceedings, publication of which began in 1854, contain various early contributions to ichthyology, malacology, meteorology, and the study of ocean currents—one of the latter, the Davidson Current,: being named after George Davidson, President of the Academy from 1872 to 1887. Since the turn of the century the Academy has conducted a number of sea-going expeditions, with vessels obtained for a limited time either with Academy funds, by private philanthrophy, or through the co-operation of State or Federal agencies. The Steinhart Aquarium, erected in 1923, provides facilities for the study of the life-history, behaviour, and physiology of marine organisms. The Hopkins Marine Station of Stanford University established in 1892, is regarded as a centre of research in physiology and experimental. biology, rather than oceanography. It has, however, made numerous substantial contributions to the latter science. As examples, one may mention the work of Jordan and Gilbert on marine fishes, Fisher on Asteroidea, Bolin on both littoral and deep-sea fishes, G. M. Smith on marine alge, and Skogsberg on temperatures in Monterey Bay in relation to currents. The Pacific Biological Station, Nanaimo, B.C., was established by the Biological Board of Canada in 1908, mainly as a centre of fisheries research. In that connection it has had occasion to carry on a great deal of fundamental research on the life-history and ecology of marine organisms, both vertebrate and invertebrate. In recent years its work has extended increasingly into the field of physical oceanography, as evidenced by the recent publication of six volumes of mimeographed reports on temperature, salinity, and density at several stations from Dixon Entrance to the Strait of Juan de Fuca. Tully’s studies of the mixing of fresh and salt water in coastal areas have opened up a field that may profitably be explored by institutions lacking facilities for deep-sea work. 169 * The Bureau of Marine Fisheries of the California Division of Fish and Game, whose laboratory at Terminal Island was established in 1921, has expanded rapidly into sea-going investigations, and one or more of its vessels are presently being equipped for full-scale oceanographic work in connection with the investigation of the California sardine. It is likely that the corresponding State agencies in Oregon and Washington, conducting excellent work in the investigation of marine fisheries, will find it increasingly necessary to expand into the oceanographic field. The United States Fish and Wildlife Service.is conducting large-scale investigations in the Pacific area. It is not possible in a report of this scope even to detail those being carried on along the Pacific Coast of North America. The Service has been active in the investigation of substantially all important Pacific Coast fisheries, and has given attention to improvement of methods, gear, &c., for the collecting of the eggs and larve of pelagic fish, and the collection of other plankton organisms. One should not omit reference to the important work of the U.S.S. ‘““ Albatross,” which spent much time between 1901 and 1917 in Pacific Coastal waters. The survey of San Francisco Bay, 1912-1913, is out-: standing. _ The Laguna Beach laboratory of Pomona College, established in ~ 1911, the Coos Bay laboratory, established in 1937 under the Oregon State System of Higher Education, the Pacific Biological Station estab- lished by the College of the Pacific at Dillon’s Beach, California, in 1947, and the laboratory established the same year at Anacortes, Washing- ton, by Walla Walla College are primarily teaching laboratories for the training of undergraduate students. Doubtless the research aspect will be increasingly developed as time goes on. However, it should be remarked that the training of undergraduate students in marine science is in itself an important end, and not at all to be minimized. From these laboratories may come many oceanographers of the future. In conclusion, it may be stated that many of the problems of ocean- ography relate to the interaction between sea and land. Littoral ecology is a field of major importance, in which the marine biological laboratories are in a position to make a unique contribution. Every item of infor- mation contributes to the sum total of our knowledge of that vast, amazing complex that is the sea. SUMMARY OF DISCUSSION That oceanography was at present being treated from the point of view of the whole range of the subject was emphasized by Dr. Foerster, who remarked that Marine fisheries, for instance are being developed at the Pacific Biological Station, Nanaimo, as well as other oceano- graphical and biological projects, although handicapped by shortages of personnel and equipment supply. Dr. Hubbs pointed out that Dr. Miller’s review was intended to be exclusive of the work of the University of Washington Oceanographic Laboratory and the Scripps Institution, which would be reviewed later. A tribute to the large numbers of small fishing craft, and to the invaluable help continually received from fishermen was paid by Dr. Frances Clarke. Dr. Johnson concluded with an appreciation of the werk of the U.S. Navy, particularly the Navy Electronics Lakoratory. “170 REPORT ON THE MARINE RESEARCH WORK OF THE ALLAN HANCOCK FOUNDATION By JouN F. KESSEL, School of Medicine, Los Angeles - | Abstract] The biological survey of the Eastern Pacific from San Francisco to San Juan Bay, Peru, which has been due to-the able assistance and co- operation of Captain Hancock with his“ Velero III,’ has established to date approximately 1,650 shore and dredging stations. This work is shallow water on the whole with the major part being done in depths under 100 fathoms. Much time has been consumed in getting the large collections properly housed in Hancock Hall, in negotiating and trans- ferring to the Pacific Coast the taxonomic reference library of the Boston Society of Natural History, and the training of advanced graduate students to begin the study for taxonomic monographs of the faunas and floras of the area. Eighty-two separate reports, ranging from descriptions of new species to monographs, have been. published. SUMMARY OF DISCUSSION Dr. Emery supplemented Dr. Kessel’s general review with some remarks of interest to marine geologists on the bottom sediments and on the physiography of the area. He described a series of basins, eleven in all, extending outwards beyond the coast, each with different bottom depths and different grades of sediment. Those nearest the shore had coarsest sediments and were widest and flattest, with increasing ir- regularity and fineness of sedimentation on proceeding seawards. ‘The history of these basins was thought to be of importance in the interpre- tation of the Los Angeles basin. Work was described on the intersection of the salinity and temperature curves in the various basins, and the sediments in the Los Angeles basin were stated to be of particular importance from the point of view of oil prospecting. OCEANOGRAPHIC DEVELOPMENTS IN THE HAWAIIAN AREA By Ropert W. Hiatt, University of Hawaii HISTORICAL INTRODUCTION It is my purpose to present a review of oceanography in the Hawaiian area and to examine critically impending developments which, for the first time in our history, portend concentrated analyses of a localized, subtropical island area. Oceanography as a science had its inception in Hawaii one hundred and seventy years ago when Captain Cook and his staff of scientists visited the Archipelago near the end of the eighteenth century. For the next half-century a series of notable explorers and investigators visited Hawaii and returned to Europe with collections of the flora and fauna and copious notes on hydrographic features of interest to mariners. The first intensive investigation was made by Americans of the U.S. Exploring Expedition of 1838-42. This was followed by the first great oceanographic expedition to circumnavigate the globe, the ‘“‘ Challenger ’’ Expedition of 1873-76. In 1902 the U.S. Fish Commission steamer ‘“‘ Albatross ”’ visited Hawai for the primary purpose of investigating the deeper waters about the Archipelago. Thus, although the waters reach great 171 depths about Hawaii, it is as Edmondson (1959, 593) states,“ . . . an obvious fact that we began investigation of the marine fauna of the Pacific on the. bottom and worked up.”’ In November, 1947, the Swedish Deep-Sea Expedition, under the direction of Dr. Hans Pettersson, visited Honolulu and occupied several stations in the vicinity of the Archipelago. The U.S. Navy has collected many bathythermograph records and depth soundings in the Hawaiian region which are being processed by the Scripps Institution of Oceanography. SHORESIDE LABORATORIES One of the most significant developments in oceanography in Hawati is the establishment of the Hawaii Marine Laboratory. This laboratory, under the general control of the University of Hawaii but operated in close co-operation with the University of California, was made possible by the generosity of Edwin W. Pauley and four associates, owners of Coconut Island in Kaneohe Bay. Available on Coconut Island now ‘are several excellently constructed tidal ponds varying in length from 40 ft. to over 600 ft. These ponds are walled with cement or coral blocks and are separated by an elaborate system of metal screen gates. On shore are several banks of sunken tanks and glass-fronted aquaria which range in capacity from 100:to 10,000 gallons. Excellent docking facilities and a marine railway capable of handling boats up to 50 ft. in length are part of the physical plant. To supplement these unrivalled outdoor facilities the present net house on the dock will be enlarged and divided into laboratory rooms. Plans have been made and partly implemented to install the most modern equipment to facilitate the most exacting research. We trust that the importance of this station will expand and that its benefactors will increase their interest commensurate with the growth of the undertaking. Plans are being formulated for the erection of a large laboratory and administrative centre for the vast Pacific Oceanic Fishery Investi- gation established to conduct research on the pelagic fishery resources in the central Pacific area. This laboratory will be situated on the campus of the University of Hawaii where close co-operation between the scientific staffs of both organizations will be effected. The now universally recognized relationship between basic oceanographic studies and applied fishery programmes will be implemented by enmeshing an intensive oceanographic programme with the fisheries investigation. Laboratory facilities, floating facilities, and a large technical staff of oceanographers will thus be stationed in Hawaii. FLOATING FACILITIES The “ Salpa’’ is owned and operated by the University of Hawaii and is the station vessel of the Hawaii Marine Laboratory. A diesel- powered, 46{t. boat, the “Salpa”’ is outfitted for in-shore and short off-shore work around the main Hawaiian Islands. It carries a winch to operate plankton nets and dredges to medium depths, the latest type of both compressed air and self-contained diving apparatus, and fishing gear for several types of fishing operations. A feature of great utility is a 500-gallon live-well, through which sea-water is circulated at 100 gallons a minute, which serves to return specimens to the laboratory alive. : 172 The “ Makua,”’ operated by the Division of Fish and Game of the Territorial Board of Agriculture and Forestry, is a 65 ft. diesel craft which has been converted to a general purpose fishery and oceanographic ° vessel with a 3,000 mile cruising range. It carries winches for deep-sea dredging and net hauls as well as for both bathythermograph observations and light plankton hauls. Sufficient Nansen bottles and reversing thermometers to initiate the programme of physical oceanography are on hand. The “ Makua’”’ also carries an improved type of live-well in which the water may circulate at 400 gallons a minute. . The conversion of the three vessels to be operated by the Pacific Oceanic Fishery Investigation in the pelagic fishery investigation is in progress. One of this trio of vessels will be converted into an oceano- graphic research vessel. The remaining vessels will be outfitted mainly as fishing craft. This fleet, in addition to.the vessels mentioned above, will comprise a concentrated supply of research vessels in Hawaii and the central Pacific which should provide abundant physical facilities. RESEARCH PROGRAMME The current research programme can best be presented in three phases, although all are closely integrated :— Physical Oceanography.—The Scripps Institution of Oceanography has issued recently completed reports on the analysis of bathythermo- graph records and echo soundings taken in Hawalian area during and subsequent to the war. These reports describe the diurnal and seasonal variation in sea temperature and vapour pressure, the variation in salinity, and the bottom contours for several miles out to sea in the vicinity of Kaneohe and Hilo. A long-period wave-recorder or tsunami recorder, designed at the Scripps Institution, has been installed in the Hawaiian Islands. This device suppresses by hydraulic filtering short-period wind-waves and swell and very long-period waves such as the tides. This instrument has a Maximum sensitivity of periods of one hour and is designed to cut out tides of a mean range of 15 ft. It will record waves primarily in the period range from six minutes to six hours, and of amplitude of less than | in. as well as tsunamis of amplitude of 6 ft. to 8ft. The study of such records will lead to results of considerable geophysical interest, and an instrument in the Hawaiian Islands is particularly desirable because of the frequency of occurrence and magnitude of tsunamis there. With the completion of the Hawaii Marine Laboratory the Univer- sity's research plans will be implemented. These comprise a study of those aspects of oceanography peculiar to this subtropical region. Broadly speaking, the physical oceanographic programme may be called a study of the ecology of the near-shore and off-shore waters around the islands of Hawaii and the study is readily divided into three parts: (1) ecology of the in-shore waters (?.e. primarily the waters inside the reefs of Kaneohe Bay), (2) ecology of the transition region beyond the reef, (3) ecology of . the oceanic waters. These subdivisions are established for the following reasons: the very near-shore waters have their endemic faunal and floral populations but these waters are also nursery grounds for much of the food of pelagic fishes. Within many of the near-shore areas there is a rapid exchange of 173 water with the outside, and it appears possible that a considerable amount of the organic matter present off the reef area is produced on and inside ‘the reef. The region directly beyond the reef is another ecological sub- division, distinct in character from the oceanic water at greater distances from the shore. How far the near-shore effects reach is unknown. Simi- larly, it is not known if the off-shore waters are uniform or if variable conditions related to external influences such as variable winds or upwelling are commonly encountered. A brief outline of the programme contemplated at the Hawaii Marine Laboratory is outlined in Pacific Science (Hiatt, 1948, 67). The Hawaiian Tuna Packers Corporation is entering the field of fundamental oceanographic research where results are likely to lead to immediate applications beneficial to the industry. Scheduled for installa- tion on their research vessel in the very near future is a submarine detector unit and oscilloscope with which they plan to study the sounds made by skin friction of pelagic fish. This apparatus will record vibrations up to 100,000 cycles, and it is hoped that sufficient differentia- tion can be observed between the several species of tuna and other tuna- like fish so that the detection of individual species by the oscilloscope record will be possible. The practical applications of such a device are obvious where at least four species of tuna occur, some of which are much more desirable than others. A second project of great significance involves the use of sonic means to herd fish either by repelling or attracting them. Considerable data on the response of fresh-water fish to sounds of various frequencies are available, but to my knowledge little or nothing is known about this phase of behaviour of pelagic species. Interaction of Biological Processes and Their Controlling Factors.— Experience of the last few years has demonstrated conclusively that fundamental oceanic biology, concerned with the interaction of biological processes and the multiple controlling factors involved in the production, distribution, and fluctuation of marine populations requires the combined efforts of a group of experienced investigators participating in a carefully co-ordinated programme of basic research. A programme of this nature forms the essential liasion between physical oceanography and fisheries biology, but distinct in scope and in personnel requirements. Kesults of such studies provide the basis for regional productivity, a subject grossly misunderstood in tropical and subtropical oceanic waters. An investigation of the production of food by plankton in Hawaiian waters was initiated this year by oceanographers at the University of Hawaii in co-operation with fishery biologists at the University and the Division of Fish and Game. Further co-operation and considerable expansion of the programme is anticipated when the staff of the Pacific Oceanic Fishery Investigation is established at the University. The over- all objective of the study is to analyse the production of food, by plankton, for higher animals in both the neritic and oceanic provinces of the sea adjacent to Hawaii as related to the complete environment. First, an investigation of the zoo-plankton production involving both qualitative and quantitative studies will be made, with the latter aspect resolved in terms of organic material per unit volume of water. The study will embrace the food chains consisting of microplankton, macroplankton,. and the food of fish as related to geographic, seasonal, and bathymetric 174 distribution. Second, an investigation of the geographic, seasonal, and bathymetric distribution of the phytoplankton will be made. Third, an investigation of the currents, © fertilizer salts,’’ oxygen concentration, and the penetration of light, all factors which influence photosynthetic activity in the water, will complete the project. This undertaking is of great significance both to the fundamental concepts of oceanography in the tropics and to studies of commercial fisheries. It will coincide with the programme recommended by the Pacific Science Conference (Pacific Scz., 1 (1) 59, 1947), with the pro- gramme of physical oceanography to the initiated at the Hawaii Marine Laboratory (Hiatt, 1948), and with the pelagic fisheries investi- gation to be undertaken by the Pacific Oceanic Fishery Investigation in the central Pacific. There is neither sufficient staff nor funds available at present to launch the complete study, but a “ pilot operation ’’ to define major trends for later investigation was initiated this year. We expect it to show whether there is a marked variation in the plankton seasonally, bathymetrically, or geographically ; to produce many of the larve of fish and invertebrates important in piecing together life-histories now being studied ; to indicate what food organisms are available to pelagic fish ; and to assay the contribution of the reef and shore fauna to the pelagic realm surrounding the Islands. Other active research projects which dovetail into this major study include (1) a study of the relation of the reef and shore fauna to the economy of the neritic and oceanic regions, (2) a study of the life-histories of fish having pelagic larval and post-larval stages, (3) a study of the life cycles of invertebrates important in the food-chains leading to fish of commercial importance, and (4) a study of the food and feeding habits of pelagic fish in the Hawaiian area. Applied Oceanography.—Aside from naval uses, applications of oceanographic information have been and are being made principally in fishery biology. Four agencies are co-operating closely in carrying out this phase of the work. The Co-operative Fisheries Research Statt of the Territorial Division of Fish and Game and the University of Hawaii has been engaged in various aspects of fishery research for the past three years. Present projects comprise (1) a study of the biology of ‘the tuna baitfish (Engraulis purpureus) in which the distribution, population trends, reproductive cycle and potential, localized endemism (racial studies), age and growth, food and feeding habits, and methods of catching and holding are receiving most attention, (2) a study of pollution in Hilo Harbour which has virtually removed this port as a tuna fishing centre because of the rapid mortality of baitfish held in bait wells under present conditions, (3) a study of experimental trolling techniques for tuna in which deep trolling in relation to the thermocline is being tried for the first time, (4) a study of the occurrence of egg, larval, and post-larval forms of the tunas in the high seas of the Hawaiian area, (5) a morphometric study of statistically proven characters of Hawaiian tunas to ascertain the racial composition of the stock and to compare Hawaiian tuna with tuna, reputedly conspecific, in other sections of the Pacific, and (6) several studies on invertebrates, including ecological succession on developing coral reefs, the sponges of Hawai, and the snapping shrimps of Hawai. This latter study 145 may prove of considerable value in demonstrating that Hawaii is the most suitable area for more detailed studies of the role of the snapping shrimp in the production of underwater noise in the sea (Johnson, et al, 1947). Many fishing-vessels in Hawaii are installing recording fathometers for spotting schools of fish at various levels above the bottom. Phenomenal catches have been made using this instrument as a seeker. The sonic research vessel of the Hawaiian Tuna Packers is being equipped with modern devices to analyse schools of fish horizontally and vertically by echo sounding, and should experiments prove the practicability of speciating tuna by skin friction noises and herding them by sonic beams, a new era in catch methods will be ushered in. The extensive programme of the Pacific Oceanic Fishery Investigation will include a considerable amount of fundamental as well as applied physical and biological oceanography. The staff of the U.S. Weather Bureau in Honolulu has been active in devising means of forecasting swell and wave heights by analysing © daily weather maps. Thus far they have been highly successful, and on several occasions warnings have been broadcast to operators of small craft and to occupants of homes near the tide line of impending danger to equipment in time to effect measures for safety. Bibliographic ; Analyses of Oceanography in the Pacific—Of con- siderable importance in establishing and assessing research programmes on oceanography in the Pacific is the exhaustive analysis of literature and unpublished documents on Pacific oceanic biology which is being carried out under Navy contract at the Woods Hole Oceanographic Institution. When the project is completed a firm basis for planning future investigations will be available. Several members of the staff of the University of Hawaii are engaged in translating from the Japanese Utinomi’s Bibliographica Mucronesica (1944). Sections dealing with invertebrate zoology, oceanography, and limnology are nearing completion. The chordate section including that on fish has been completed and published by Fisher (1947). The translated bibhography is expected to be published by the University of Hawaii Press. HAWAII AS A LOCALE FOR INVESTIGATIONS IN TROPICAL OCEANOGRAPHY Space will not permit me to annotate as fully as 1 would wish some of the more fundamental problems which, when solved, will enable us to understand the tropical seas as well as we do our temperate waters. With respect to the general biological economy of tropical and sub- tropical seas we must study (1) the quantities, rate of growth, and food complexes of the organisms present, (2) the role of bacteria in various locations in the warm sea, (3) the tropical and subtropical plankton compared with temperate plankton in regard to organic content, metabolic rate, seasonal fluctuation in abundance and position bathymetrically, and its efficiency factor in foodchains. Many vexing problems in the distribution of the Indo-Pacific fauna eastward will not be solved until we learn more about the ecology of the larval phases of littoral species, the span of their larval existence, and the ocean current system responsible for their transportation. I need not point out the great need of taxonomic studies on the marine fauna and flora of central Pacific areas. 176 Of monumental importance is the need for an accurate analysis of the scattering layers or false bottoms found so abundantly at depths of a few hundred fathoms in many areas of the Pacific. The most recent accounts of vast stretches of such layers are reported by the staff of the Swedish Deep-Sea Expedition aboard the “ Albatross ’’ (Pettersson, 1948). Scattering layers with rough borders which return echoes characteristic of comparatively large and densely packed organisms were found repeatedly when crossing the bands of convergence bordering the equatorial countercurrent. Below these areas of convergence cores taken with the piston core sampler (Kullenberg, 1947) varied from nearly pure radiolarian ooze to nearly pure globigerina odze, indicating strips of highly productive ocean area. That this reflective layer may be related to a vast, untapped deep sea fishery is by no means outside the realm of probability (Chapman, 1947; Hahn, 1948: 104; Pettersson, of. czt.). In regard to physical oceanography the effects of oceanic islands on currents, upwelling, and regional productivity are rather easily studied in Hawaii. Studies on penetration of light in clear oceanic water and studies on submarine photography are especially applicable. Various aspects of submarine geology associated with volcanism and erosion are easily accessible for investigation. We are aware that an efficacious programme in oceanography resides in a carefully co-ordinated effort in which many agencies with experienced personnel and specialized equipment participate. We look to the newly organized U.S. Committee on the Oceanography of the Pacific to provide the guiding hand in devising a co-ordinated approach to the vast problem. Thus we recognize a twofold responsibility in Hawaii—first, to undertake portions of the programme for which we have personnel and equipment ; and, second, to provide working space and facilities for personnel of co-operating agencies. With the assurance that the University and associated institutions in Hawaii are vitally interested in mid-Pacific oceanography and are striving to further research in this sphere to the extent of their facilities, suggestions for co-operative efforts with other institutions in the Pacific are indeed welcome. REFERENCES CHAPMAN, W. M. (1947): The Wealth of the Ocean. Sci. Mon., 64 (3), 192-197. Epmunpson, C. H. (1940): The Relation of the Marine Fauna of Hawaii to That of Other Sections of the Pacific Area. Sixth Pac. Sci. Cong., Proc., 3, 593-598. FisHerR; H. I. (1947): Utinomi’s Bibliographica Micronesica : Chordate Sections. Pacific Sci., 1 (3), 129-150. Haun, J. (1948): Woods Hole Oceanographic Institution. Turtoy News, 26 (4), 98-104. Hiatt, R. W. (1948): Preliminary, Note on the Oceanographic Program of the Hawaii Marine Laboratory. Pacific Sci., 2 (1), 67-68. Jounson, M. W.; Everest, F. A.; and Youne, R. W., (1947): The Role of Snapping Shrimp (Crangon and Synalpheus) in the Production of Underwater Noise in the Sea. Biol. Bul., 93 (2), 122-138. IXULLENBERG, B. (1947): The Piston Core Sampler. Suwenska Hydy. —Biol. Kom. Skriftery III, 1 (2), 1-4°. Pettersson, H. (1948): The Swedish Deep-sea Expedition. Pacific Sci., 2 (4), 231-238. Utinoul, H. (1944): Bibliographica Micronesica/Scientie Naturalis et Cultus. 208 p. Hokurytikan Pub. Co., Tokyo. aC (TE SUMMARY OF DISCUSSION Dr. Johnson inquired whether marine geology was to be included within the Hawaii project. Dr. Hiatt replied that there was no submarine geologist at Honolulu at the present time, but that it was hoped to provide facilities in the programme for geology as soon as sufficient interest developed. In answer to a query about wave recording, it was stated that tide measurements were to be made, but that there was no particular work about to be commenced on waves. REVIEW OF CANADIAN PACIFIC OCEANOGRAPHY SINCE 1938 By Joun P. Tutry, Pacific Biological Station, Nanaimo INTRODUCTION Until 1943 oceanography on the Pacific Coast was sponsored by the Fisheries Research Board, and was directed entirely to fisheries objec- tives. From then until 1947 the facilities were diverted to naval purposes under the direction of the National Research Council. In 1946 the Joint Committee on Oceanography was formed by pooling the requirements and allotments of the Fisheries, Navy, and National Research Council in this field of research. Atlantic and Pacific Oceanographic Groups are established with headquarters at the respective biological stations, and vessels manned and operated by the Navy. Technical assistance and equipment is provided by the National Research Council. This inter- departmental co-operation has greatly increased the horizon and capabilities of Canadian oceanographic research. aa H.M.C.S. ‘‘ CeEpARWoopD,”’ A CANADtAN OCEANOGRAPHIC RESEARCH SHIP 178 To date most Canadian oceanographic studies in the Pacific have been located in the coastal regions and the inland seaways, and in con- sequence have been primarily concerned with the influence of fresh water in the sea, and related phenomena. THE FRASER RIVER PROJECT The influence and limits of the Fraser River in the sea has been the subject of investigation by Canadian and United States oceanographers | for the past twenty years. These include the studies by the University of British Columbia, the University of Washington, the Pacific Biological Station, and the Canadian Navy. These data are being consolidated into a coherent digest by the Oceanographic Laboratories at the Univer- sity of Washington and the Pacific Oceanographic Group. The Fraser River outflow system contains one of the wealthier fisheries of the Pacific coast, and is the subject of considerable fisheries research. Further, the system provides a wide variety of oceanographic conditions with virtual temperature gradients representative of Arctic, Temperate, and Tropical seas. As such, it is of primary importance as a region for naval underwater research. It was found that the Fraser River spreads out in Georgia Strait, most of the water moving anti-clockwise around that basin, mixing with the underlying sea-water en route. It passes to the sea, through a faec —— Sims 124° 123 6 Pv FRASER RIVER $ INFLUENCE a 7 Pa Fraser River Water» Mixed With Seawater Re 5 iid SSeS wz = Cy KS) , ost Viger \ a = Coumbio River sy ¥ Woter SES t = my : aat-—/| + ) a 126° Sealy of Distance region of extreme turbulence in the Washington Archipelago, where the 30 ft. to 40 ft. depth of brackish surface water, originating in the Fraser River outflow, becomes mixed with about 600 ft. of dense sea-water, provided by tidal circulation from the zone of up-welling along the ocean coast. Evidence of fresh water from the Fraser River is lost in this process, so that the outflow from Juan de Fuca Strait is more saline than the approaches.to many of the smaller drainage systems in the vicinity. The outflow from Juan de Fuca Strait is evidently maintained by a hydraulic head established in Georgia Strait and Puget Sound. Emerging from the strait it veers to the right and moves northwestward along the Vancouver Island shore. This stream is subject to annual variation related to the fresh-water discharge from the Fraser River and the seasonal winds, which are south-east in the winter and north-west in the summer. Within a distance of approximately 30 miles the energy of the northwestward flow is dissipated in eddies, the water is absorbed into the California current off-shore, and moves southward in the Oceanic circulation. ; This research was interrupted by the Alberni project (see below) and the war. Preparation of the report for publication is now under way. THE ALBERNI PROJECT In 1939 it was required to predict the state of pollution that would result from a proposed sulphite-pulp mill to be established at the head of Alberni Inlet on the west coast of Vancover Island. This seaway is typical of many of the “ fjord type ” inlets along the British Columbia and Alaska’ coast, which, oceanographically speaking, are two- dimensional estuary systems. De or OF ALBERNI INLET 35 Seo Mites | ca ed JUNCTION } INNER, THRESHOLD ELEVATION ° OF IMPERIAL EAGLE CHANNEL ALBERNI INLET SHOWING MAXIMUM DEPTH OF CHANNEL Figura! PLAN AND ELEVATION OF ALBERNI INLET 180 1 {J ae Boe 7 Taiieen al Scale of Area x10%san 3 1 | STATION h G F E 1b) Cc B ! ie) 3 | ri CHANNEL PASSAGE , ALBERNI INLET de yidep 40 8/095 ~ It was apparent that the only pollution character of consequence was the oxygen demand of the waste sulphite liquor. If pollution was to be avoided it was necessary that the mill sewage should be displaced from the mill-site to the open sea before the dissolved oxygen content of the inlet waters was lowered by 50 per cent. An intensive oceanographic investigation showed that the fresh water from land drainage moved iSostatically seaward. Due to tidal energy it mixed with the ‘under-lying sea-water en route to form a brackish upper zone. The thickness, properties, and the rate of seaward displacement of water through this zone were quantitatively related to the discharge of the principal river in the inlet. There is a converse movement of ocean water in the zone immediately below this, which provides the sea-water to be mixed into the upper zone. Any fresh water transferred down- wards is held isostatically adjacent to the boundary and preferentially returned to the upper zone in the mixing process. Consequently all fresh water leaves the inlet by way of the upper zone, and none accumulates in the lower. Below the level of the threshold there is a deep zone, in which move- _ ment is generated by frictional transfer of velocity from the overlying middle zone. A hydraulic model of the head of the inlet was built, in which the tide, the fresh and sea-water, and the winds were represented. From this it was learned that the outflow of the river was a jet function, whose stream diverged until it occupied the whole width of the inlet. Seaward of this limit of divergence there was no transverse salinity gradient, and the system was effectively two-dimensional. The tidal and isostatic flow characteristics in the head of the inlet, and the course of the effluent from various sewer outlets were studied in this model, and confirmed. by oceanographic observations and float experiments in nature. ~ From these studies it was evident that if the pulp-mill sewage were diluted with*all the wash water from the mill so that it entered the upper zone of the inlet at approximately the density of fresh water it would remain in the upper zone and be continually displaced seaward. This approach to the problem permitted the fresh water in the inlet to be regarded as a tracing solution, indicating the behaviour of the proposed eifuent. It was concluded that no sewage would appear in the middle or deep zones, which would therefore be free of pollution. If sewage were dumped in these zones it would accumulate and ev entually cause pollution. The degree of pollution (P) was defined as the ratio of oxygen demand ~ of the pulp-mill sewage (BOD) to the dissolved oxygen supply (DO). The tolerable rate of discharge of sewage into the upper zone was arbitrarily defined as the amount whose oxygen demand would not exceed 50 per cent. of the oxygen supply. The pollution was considered tolerable when = Sal 0-5 (DO) < This provided a Ce definition of pollution which could be evaluated. The normal oxygen content of the incoming fresh and sea-water was observed, and the oxygen supply in the upper zone was evaluated from the observed proportions of each, and their rate of displacement through the inlet. The oxygen demand of the pulp-mill sewage was estimated 181 from the known rate of oxidation of waste sulphite liquor and its con- centration and age at successive intervals between the head and mouth of the inlet. The latter quantities were predicted from the relations: between river flow and the quantities of sewage discharge, the proportion of fresh water in the upper zone, and the displacement. It was concluded that the sulphite mill would be tolerable while the discharge of the principal river into Alberni Inlet exceeded 1,600 cubic feet per second. The discharge was less than this during three months of the year, implying that mill operation would have to be curtailed, the sewage stored over the period, or the river discharge maintained by storing water when the river was high. Industry solved the problem by building a sulphate mill whose pollution potential was within the tolerable limits of the seaway. THE BLOEDEL, STEWART, AND WELCH SULPHATE PuLP MILL AT. THE HEAD OF THE ALBERNI INLET Legend: A. Pulp-mill buildings. E. Log pond. B. Sewer outlet. F. Sawmill. C. Settling pond (Lupsi Cupsi Point). .G. Somass River mouth. D. Overflow to log pond. This installation has been checked, and the degree of pollution is found to be well within the predicted limits. At the same time further expansion is limited by the remaining margin of tolerance between the existing and limiting degree of pollution. It is to be remarked that in this case there was no problem arising from pulp fibres settling out, because the bottom of Alberni Inlet does not contribute to a commercial fishery. 182 This research is unique in that it undertakes to evaluate quantitatively the characteristics of an estuarial seaway in terms of river discharge, which is a readily observable monitoring factor. It provides a quantita- tive measure of pollution and shows how it may be evaluated from a knowledge of the properties of the pollulant, and the oceanography ot the system. Finally, it offers a precedent for the prediction of the probable degree of pollution from industrial development, which in turn permitted adjustments to be made before the fishery was damaged. The field-work was done between 1939 and 1942, but development of the data was interrupted by the war and was only completed in 1948. The research is reviewed in detail in three papers, which are to be published as a bulletin of the Fisheries Research Board of Canada (Ottawa) :— (1) Oceanography of Alberni Inlet. J. P. Tully. (2) Prediction of Pulp Mill Pollution in Alberni Inlet. J. P. Tully. (3) A- Hydraulic Model of Alberni Harbour. J. P. Tully, H. J. Hollister, R. L. Fjarlie, and W. Anderson. i 1322 ‘ tong. 128° W F (24° : Y a” 4 3 O Oy A | Ts rs) DIXON ENTRANCE P é 2 Location of Stations Meking 753° Daily Seawater Observations Gtetions ee Undertined es Largro.t BRITISH ae Cope St. James QUEEN a Q COLUMBIA CHARLOTTE sounp ies s 50} | PACIFIC OCEAN 4s4+— a | | 132° 128° 124? | BritTIsH COLUMBIA “T83 CHATHAM PROJECT At the present time the Pacific Biological Station is making an intensive investigation of the sock-eye salmon fishery associated with the Nass and Skeena Rivers. These are large rivers (2,500 to 250,000 cubic feet per second discharge) entering the inland seaway (Chatham Sound) near the boundary between British Columbia and south-eastern Alaska. A proportion of the salmon fishery occurs in Chatham Sound beyond the geographic limits of either river. An intelligent study of the fishery in the sound requires a knowledge of the influence and varia- tions of the river in that area. The oceanographic problem is to determine the course and influence of these two rivers in the region, from the time of maximum river discharge (May) to the minimum (September) and the variations introduced by the prevailing winds and tidal cycle. The field investigation has continued from 10th May to 10th September, and a preliminary report is in preparation. LIGHTHOUSE PROJECT A programme of daily observations of the sea-water temperatures and salinities was initiated on the Pacific coast of Canada in 1917 with one station. This has been increased at intervals, until the present total of eleven stations was reached in 1939. Most of the observations are made from coastal lighthouses, which explains the project designation. The seasons are shown in the temperature data, and the integral effects of land drainage are shown in the salinity records. The small fluctuations are attributed to wind effects, since off-shore winds cause upwelling and a consequent decrease in temperature and increase in salinity. On-shore winds have the converse effect. The duration of any combination of conditions is indicated by corresponding steady states -in the records. Oceanographic surveys are tedious’ and costly undertakings which cannot be repeated indefinitely, and from which the conclusions usually are not available before the observed situation has passed. However, it may be assumed in most cases that the oceanographic state is deter- mined by the season, weather, tide, and runoff whose integral effect is reflected in the conditions at one point in the region. Therefore oceano- graphic surveys are usually undertaken to observe type states in terms of the controlling factors, and the conclusions related to the appropriate lighthouse observations. This allows the recurrence of the observed state to be recognized from these data alone—that is, the lighthouse data serve to identify the conditions under which occasional oceanographic observations are made, their duration, and frequency of repetition. The daily observations provide a complete calendar of events in the coastal ocean and seaways, by which present data may be made applicable to the past and future. It is the purpose of this investigation to accumulate these records as reference data for all other investigations in the Canadian coastal seas, to determine their significance as submarine climatological indices, to determine their relations, if any, with the success of coast fisheries, to evaluate annual cycles and trends, and geographical differences. Their use has been somewhat delayed by the War, but this process of examina- tion is begun, anf studies based on the data may be anticipated. 184 DAILY SEAWATER TEMPERATURE SALINITY AND WIND DIRECTION AT AMPHITRITE STATION OURING 1936 [ van [rea [ war [sea [ may [une | suey | ava | seer [oct [ nov | oec. aa SEA WATER TEMPERATURE 40 ! WIND DIRECTION DaILty SEAWATER TEMPERATURE The data are being published in mimeographed volumes which may be obtained on application to the Director, Pacific Biological Station, Nanaimo, B.C. OBSERVATIONS OF SEA-WATER TEMPERATURE, SALINITY, AND DENSITY ON THE PACIFIC COAST OF CANADA Volume I: 1914 to 1934 inclusive .. Now available. 7 II: 1935 to 1937 inclusive is a ; III: 1938 and 1939 By 5 I\Wee NGO) aye IGEN oe A i V: 1942 and 1943 .. fe Bi, V1: 1944 and 1945 I 4) VIL: 1946 and 1947 .. as a Re VIII: 1948 and thereafter to be issued in annual volumes. 185 H.M.C.S. “ EnKoui,” a CANADIAN OCEANOGRAPHIC RESEARCH SHIP PVANS) GOK. ANY OCZEANOGRAPEICAI BG? Did ON GaN peste SOULE PACIFIC YN 950=1952 By Anton F. Bruun, Zoological Museum, Copenhagen SUMMARY OF DISCUSSION PROFESSOR YONGE inquired whether it was hoped to bring back any deep-water material alive. Dr. Bruun replied that cool acquariums were to be installed, but that it was in general hopeless to try to secure pelagic material in an undamaged Tivine! state, since the nets filled with siphonophores: and other coelenterates which killed the delicate plank- tonic animals. It was, however, hoped to keep benthal invertebrates alive. The question of alcohol and formalin preservative supplies was going to be difficult, but freezing methods has been suggested for preservation. In answer to Dr. Shepherd’s question whether it was proposed to take bottom cores at great depths, Dr. Bruun announced the full co- operation of Dr. Pettersson, who had made a piston available. It was stated further that the three Scandinavian nations would in all probability agree to maintain a joint international research vessel. Dr. Hubbs wished to know whether it was proposed to concentrate entirely on bottom fauna or whether also very deep bathypelagic hauls were projected. It was stated that on this expedition only 10 per cent. of the hauls were to be taken at lesser depths than 1,000 metres of cable. The remaining 90 per cent. were to be bottom hauls and bathypelagic at over 1,000 metres. The type of net proposed was to be a three-boarded otter trawl. As to the problem of getting it down to the required depths, it was not thought that this would cause great dificulty. No trouble 186 had been experienced in the “ Albatross ”’ expedition, and on this occasion the wire weighed as much as 18 tons. Checking the depth of the net was discussed, for it was pointed out that the deep sea may not have an even bottom, but may show many irregularities which echo- sounding would be able to detect. THE PACIFIC CRUISE OF THE SWEDISH DEEP-SEA EXPEDITION By Hans PETTERSSON, Goteborg (Communicated by Anton F. Bruun) On 27th August, 1947, the Swedish Deep-sea Expedition on board the four-masted motor schooner “ Albatross” (1,450 ton d.w.) started from Balboa for the Pacific part of its circumnavigating cruise(1). Our equipment, including the long ~~ piston-core’’ samplers (Dr. B. Kullenberg)(2), the special Bofors depth-charges, exploding at 300—3,500 fathoms, with surface hydrophones and oscillograph or wire-recorder for recording deep sediment echoes (Professor W. Weibull)(3) had been tested with good results from the Government research ship “ Skagerak ” during an experimental cruise to the western Mediterranean in 1946(4). During our first Atlantic crossing, Madeira—Martinique, long cores had been successfully raised from great depths, and the thickness of the sedi- ment carpet measured. The ship, prior to the start, had been converted into a floating laboratory with cabins for a science and technical staff of ten to twelve, spacious laboratories for different purposes, workshop, aquarium, special cool-storage for the sediment cores, &c. In the fore hold the large electrically driven deep-sea winch, capable of hoisting a load of up to 10 tons with a maximum speed of 100 metres per minute, together with a wire drum holding up to 12,000 metres of wire rope, had been installed. In the aft hold the diesel-electric plant energizing the winch with 140 k.w. was placed. Other winches on deck included a “‘series-winch ”’ for water-sampling and reversing thermometers with 9,000 metres of 4mm. wire rope, a cable winch for subsurface light measurements, &c. A special feature was the recording echograph, especially made by Marine Instruments Co. of London, which, under favourable conditions of wind and swell, drew continuous records of the bottom profile to within I or 2 fathoms, down to depths exceeding 4,000 fathoms. The very heavy gear used made it advisable to lay the course largely within the equatorial calms, avoiding as far as possible latitudes beyond 20° North and South. This, on the other hand, called for air-conditioning ‘of the cabins and laboratories in order to keep the staff efficient in the warm and moist climate met with. The itimerary had also been chosen so as to minimize the risk of being hampered in our work by hurricanes, typhoons, and adverse monsoons. Actually very few working days were lost through bad weather. rae . The Pacific cruise included four complete sections across the.counter- equatorial current and its neighbourhood where frequent oceanographic stations down to the bottom and still more frequent temperature measure- ments in the upper layers, made by means of a bathythermograph, were carried out, affording unique material for future dynamic analysis. The ART echographs from these crossings gave evidence of reflecting layers indicated by diffuse “false bottoms ’”’ in moderate depths, between 50 and 150 fathoms generally, which had a tendency of moving upwards towards the night. In some cases they apparently consisted of shoals of fish, in others, possibly, squids or else densely packed planktonic organisms. For lack of proper gear no samples could be taken. They appear to be associated with the strips of divergence—7.e., upwelling water, rich in nutrient salts, which border the counter-equatorial current. The bottom samples taken by means of the corers, up to 16 metres in length, gave evidence in the same region of multiple stratification, noticed already from the “ Challenger ’ cruise. Probably the equatorial current system has become displaced in latitude by changes in atmospheric circulation, accompanying the’ variations from glacial to interglacial epochs. An interesting but rather unfortunate fact was the highly irregular bottom profiles met with here as well as in the Atlantic and the Indian Oceans, where a perfectly flat bottom is rather the exception than the rule. Moreover, where a perfectly level bottom occurs, it sometimes consists of an extensive lava-bed, covered by a thin veneer of sediment. Both circumstances repeatedly led to loss of instruments. The echo- sounding of the sediment thickness gave considerably smaller distances between the sediment surface and the reflecting layers beneath the sediment (presumably basaltic bedrock) both in the Pacific and the Indian oceans (maximum 300 metres) than the far higher values found in the Atlantic (up to 2,500 metres). A total of sixty cores was raised from great depths (maximum 7,800 metres in the south part of the Mindanao Deep) with a maximum length of an individual core of 16 metres. Once completely investigated by mechanical, chemical, mineralogical, spectroscopic, radioactive, and biological analyses, these extracts from the “ records of the deep” may be expected to yield interesting information on the past history of the central Pacific Ocean along our course, extending back in the Tertiary Age. By means of a special water-bottle of large capacity (25 litres), samples of sea-water from different depths were collected for radium analysis (by precipitation with barium-sulphate) and for fluorescence analysis on uranium. The disturbed balance between uranium and radium in sea-water due to the precipitation of ionrum(5) to the ocean bottom together with ferric hydroxides is probably the main cause of the surprisingly high radium content of many deep-sea deposits, especially of the Red Clay. Incidentally, the ionium affords a clue to the dating of the different strata from radium measurements. Measure- ments of submarine light in different spectral regions were carried out, partly by means of rectifying cells, down to 200 metres, partly by means of a submarine camera, down to 500 metres (Drs. N. G. Jerlow and F, Koczy). Near the surface measurements were also carried out on the ultraviolet component of submarine daylight. The frequency of suspended particles in different depths was measured by the Tyndall method. The study of the large material collected during the cruise, with a total core-length from all the three oceans of 1,640 metres, will occupy several specialists in Sweden and also in other countries for at least 188 five years. Liberal grants for this work are being put at our disposal, covering also the editing and publishing of a special report from the Royal Society of Goteborg. It is our hope that the new technique, which has now passed through crucial tests, will be used also by other nations on the vast and almost unbroken field of research offered by the deep ocean bed, its morphology, its stratigraphy and geochemistry, and its biology. During our cruise the latter subject was reserved for the last three months’ cruise in the Atlantic Ocean, where deep-sea trawlings were made under the supervision of Dr. O. Nybelin, from the Natural History Museum of Goteborg, assisted by Dr. Kullenberg, who also mastered the coring operations with his sampler. It appears that in the coming geophysical and biological work in great ocean depths one of the most important fields is the central Pacific Ocean centred round the Hawaiian Islands and Tahiti. Honolulu seems to be designed to become the centre of this research. The most important problems are, according to my notion :— A. The chronology of the deep-sea sediments using radioactive and biological methods (analysis of foraminiferal shells)(6), possibly also volcanic ash-horizons, cosmic spherules, and, near islands with intense vegetation, pollen analysis. B. The prevalence of lava beds in great depths and other signs of submarine volcanic activity. C. The morphology of the bottom surface and of the substratum beneath it as revealed by echo-soundings, preferably by depth charges exploding below the sediment surface. D. The temperature gradient in the deep sea bottom (one of the most important tasks of modern geophysics according to Professor Jeffereys, of Cambridge). With regard to the last point it had been my intention to measure the geothermal gradient at various points along the route, for which purpose a special geothermometer, 11 metres in length and registering the difference in temperature between the surrounding sediment in this depth and the isothermal bottom water above it, had been constructed. Owing to repeated failures of the clockwork to work at the very low temperatures met with only two attempts both in the equatorial Pacific were successful: Both afforded unexpectedly high values of the geothermal gradient—viz., 22 and 26 metres per 1° centigrade respectively, which would imply a higher value of the geothermal current in the ocean bed than on the continents (possibly another indication of latent submarine volcanism). It would be rash to draw any inferences from these two isolated values until more material has been calculated by the same or- by other methods. Finally, it should be mentioned that the expedition doctor, J. Eriksson, of Eskilstuna, Sweden, a keen naturalist, made botanical excursions on the different islands where the “ Albatross’’ touched, like James Island in the Galapagos Group, Nukuhiva in the Marquesas (where borings in a peat bog on the rarely visited Tovii Plateau were carried out by Dr. G. Arrhenius, geologist to the expedition), on Tahiti and on Ternate where the Pacific phase of the cruise came to its end on 26th January, 1948. 189 LITERATURE (1) PetTERsson, H. “A Swedish Deep- Sea Expedition.” Proc. R. Society, B. Vol. 134, p. 399, 1947. Q (2) IKULLENBERG, B. The Piston Core Sampler.’’ Svenska hydy. biol. Koni: s Shrifter, Bd. 1 H 2, 1947. (3) WEIBULL, W. : “The Thickness of Ocean Sediments Measured by a Reflexion Method.’ Medd. Oceanogr. Inst. Goteborg, 12, 1947. (4) Pettersson, H.: ‘“‘ The Swedish Expedition to the Western Mediterrean, April— May 1946.” Bull. Inst. Oceanographique Monaco, n:o 919, Oct. 25, 1947. ——— a.o.:,“ Three Sediment Cores from the Tyrrhenian Sea.” Medd. Ocean, Ibst. Goteborg, 15, 1948. (5) ——— “ Manganese Nodules and the Chronology of the Ocean Floor.” Medd. Oceanogr. Inst. Goteborg, 6, 1943. (6) PHLEGER, FRED. B., JuN.: “ Foraminifera of a Submarine Core from the Caribbean Sea.” Medd. Oceanogr. Inst., Goteborg, 16, 1948. REPORT OF WORK CARRIED OUT SINCE 1939 IN THE JAVA SEAUBY DAE LABORATORY FORGINVE SimlGADONTOHGisEiian SIGN, VATE IU By J. D. F. HARDENBERG, BATAVIA THE work done by the Laboratory for Investigation of the Sea at Batavia came to a complete standstill during the Japanese occupation, and has even now not yet reached this pre-war standard due to the lack of equipment and personnel. Much of the instruments for oceanographic work have been lost or irreparably damaged, and we still have no vessel at out disposal to do work at sea, though just now I am trying to raise the funds to get two ships which, when they have arrived, will survey the whole Indo- Australian Archipelago, which for practical. matters will be divided into a western and an eastern half. In the first place salinities will be measured and charted during the different monsoons, in order to get in the course of years a more or less accurate survey of the currents between the islands. This, of course, is already roughly known and can be found in any sailing direction, but experience has shown us that details are very imperfectly known among the many channels, and these details have proven to influence the occurrence or nonoccurrence of different fish of economic value. In the second place, the problem of the nutrient salts (phosphates, nitrates, silicates), will be taken in hand. Special attention will be paid to the, if any, eventual existing limiting factors for plankton development in tropical seas. So far as our experience goes abundance of diatoms is only found in water masses with a relatively high phosphate content. Thus far never a peak in the diatom population was ascertained when the phosphate content was low as can be the case in temperate waters. _ It seems possible, therefore, that there is a limiting factor (or limiting factors) which determine the plankton growth as a whole, which means also that the problem of the productivity of the tropical seas and the problem of the nutrient salt cycle will have to be attacked from another point of view than in colder waters. Next to the question of the distribution of the salinities and nutrient salts the distribution of the fish will be studied in close co-operation with the results of the former inve stigations. 190 Special care will be paid to the problem of the river mouths, where very peculiar biological conditions are found and where a special estuarine fish fauna exists which is typical for South-east Asia. A similar fish fauna, though composed of different species, is found in the estuaries of South New Guinea. Since the last congress in 1939 the following research was carried on in the Java Sea by the Laboratory for Investigation of the Sea at Batavia :— 1. A HyDROGRAPHIC SURVEY OF THE JAVA SEA AND ADJACENT STRAITS -Four regular cruises, taking samples from the surface to the bottom, were made—viz., in the months of January, April, July, and October every year. Besides this work regular sampling was done at the surface by shipping lines and lighthouses. The total amount of water samples collected totalled up to about ten thousand a year.* Only salinities and temperatures were determined. In general it can be said that the current-system changes twice a year under the influence of the monsoons, which are the predominating winds here, the long axis of the almost rectangular Java Sea lying parallel to the direction of the monsoons. During the east monsoon water flows into the Java Sea from the Flores Sea and the Straits of Macassar and leaves it again through the Straits of Sunda into the Indian Ocean and through the channels between Sumatra and Borneo into the South China Sea. In the west monsoon the direction of the currents are just the reverse, whereas the general salinity is one to two promille lower than in the east monsoon. This changing currents system, together with the varying salinities, have a strong influence on the fisheries for Decapterus. Now and then oceanic water through the Straits of Sunda is pouring into the Java Sea in contrast with the general current system of the east monsoon. This upsets this system for the south-western part of the Java Sea and in accordance with this the general ordinary pattern of the fisheries. No publications were ready at the outbreak of the war. 2. A SURVEY OF THE BoTToM FAUNA This was done especially in the Bay of Batavia. Some interesting facts were discovered. The bulk of the bottom species consisted of molluscs. All specimens were very small, a shell of 1 centimetre was a large one. This bottom fauna proved to be totally different from the molluscan fauna generally found on the shore, which therefore must live in a very limited zone. The number of species, as always in the tropics is large. One station produced 190 species (not individuals !) per square metre. The amount of living matter, however, which can serve as fish food for bottom dwellers was very low, a fact which is not encouraging for the development of a trawl fisheries in a European style. In accordance with this the number of flat fishes (not the number of species) is smaller than f.1. in the North Sea and the individuals are small, too, 10-15 cm. being the average, some species and some localities excepted. 191 3. THE RIVER-MOUTH PROBLEM The estuaries of the tropics, or at any rate those of South-east Asia, show peculiarities which are not found in colder climates. In front of each river mouth a horse-shoe shaped bar exists not consisting of sand, but of very soft mud. In this bar no channels are found as would be the case, for instance, in European rivers. This soft, muddy bar is maintaining itself, notwithstanding the fact that heavy tidal streams, sometimes up to 5-6 nautical miles an hour, flow over it twice aday. This bar ends abruptly and very steeply to the landward and has a very gentle slope to the seaward. The result is a peculiar distribution of the salinities, water of high salinity, flowing over the bar at high tide as a kind of submarine waterfall, is captured behind the bar at low tide, and remains more or less stagnant on the bottom of the river proper. These rivers, coming from a very flat and marshy country, have a very slow fall, and the sea-water (more or less diluted) is often found tens of kilometres inland. In these waters a peculiar and very special fish fauna is found, . consisting of species (and even genera) spending their life cycle in these waters with varying salinities. This fauna does not live elsewhere. The number of species is, for a tropical community, low, the number of individuals very large, probably due to the high amount of plankton in these fertile waters. The plankton growth is much more abundant than in the open sea. i I am sorry to say that all notes and collections are lost. List OF ENGLISH PUBLICATIONS SINCE JAN. 1, 1939 Dam, L. VAN: Estimation of Chlorides in 1 c.c. Sea Water Samples by Means of Syringe Pipettes. Tveubia, deel 17/5, 1940. Dersman, H. C.: Preliminary Plankton Investigations in the Java Sea. Tveubia, deel 17/2, 1939. HARDENBERG, J. D. F.: Some New or Rare Fishes of the Indo-Australian Archi- pelago: VII. Tveubia, deel 17/2, 1939. ——— Fishes of New Guinea. Tveubia, Vol. 18/2, 1941. ——-— Development of Marine Fisheries. Roval Asiatic Society of Bengal. Science, Vol. XII/2, 1947. ——-— Some Newor Rare Fishes of the Indo-Australian Archipelago: VIII. Tvreubia Vol. 19/3, September, 1948. Jone, J. K. pe: A Preliminary Investigation of the Spawning Habits of Some Iishes of the Java Sea. Tyreubia, deel 17/4, 1940. AN QOUTZEINE, OF THE WORK OF DHE OCEANOGRAPHIE INSTITUTE OF INDO-CHINA from 1939 to 1948 By R. SERENE, Oceanographic Institute of Indo-China At the Fifth Pacific Science Congress a résumé was presented of the work of the Oceanographic Institute of Indo-China during the period 1929-1933 ; at the Sixth Congress a résumé of that carried out between 1934 and 1939. The period 1939-1948 is that of the war, the unfortunate effects of which are still being felt. M. Chevey, the Director, died in 1942; from 1943 to 1946 the labora- tory was closed, and even during the period from July, 1945, to April, 1946, entirely abandoned and given over to pillagers. In April, 1946, M. Serene assumed responsibility for the place, but found neither staff nor equipment ; the task of reconstruction and re-equipment absorbed 192 all his efforts until the end of 1947. In January, 1948, M. Marchad, a new appointee, took up his duties, followed in May of that year by M. Durand, a former member of the staff and in December, 1948, another new assistant, M. Deroux, arrived. In March, 1949, the new Director, M. Drach, will assume his functions. The scientific personnel consists of : M. Drach, Director, M. Serene, Assistant Director, in charge of the crusta- cean laboratory ; M. Durand, Assistant, in charge of the fish laboratory ; M. Deroux, Assistant, in charge of the plankton and coelenterate labora- tory ; M. Marchad, in charge of the mollusc laboratory. Professor Drach, Professor in the Sciences Faculty of the University of Paris, proposes to direct this team of biologists in the work of co- ordinating the littoral ecology, and, by means of self-contained diving equipment of the Cousteau type, to extend their researches beyond the area revealed by the spring tides, as far as a depth of 6 metres. This new technique should make it possible to prepare a table showing the various biological facies of the Indo-Chinese littoral zone, which will be a new contribution to our knowledge of tropical coastal waters. PHYSICAL OCEANOGRAPHY Until 1942 work continued without notable modification according to the general plan set out in 1936. For want of equipment and personnel this work has not so far been resumed ; it is to recommence on Ist March, 1949. In 1950 a new assistant specializing in physical oceanography, who is at present finishing his studies, will considerably widen the scope of this branch of the laboratory activity. HYDROLOGY During the period 1939-1942 these operations were confined to measurements of temperature and salinity. Several thousand observa- tions were made, both from a fixed point not far from the laboratory and during the cruises of the laboratory trawler ““ De Lanessan ”’ and other vessels. The results have been published in the Reports of the Oceano- graphic Institute of Indo-China. A paper entitled “On Annual Variations in Temperature and Saline Content of Surface Sea-water at a Fixed Point on the Annam Coast,’ which briefly summarizes some of these observations, was presented at the Congress of the International Association of Physical Oceanography at Oslo in August, 1948. During this period, owing to the lack of any vessel, the hydrological gradients which formerly were prepared twice a year along the full length of the Annam coast-line, have had to be discontinued. A single cruise of the “ De Lanessan” in 1939 made it possible to prepare a Saigon- Batavia gradient. These hydrological gradients give a great deal of information on coastal currents around Indo-China. Current movements as affecting navigation, the biology of marine species, and fishing are all considered. No work has been done as yet on the utilizing of warm waters. The laboratory has not.yet a vessel adequate to undertake these researches. No doubt by the end of 1949 one will be available. At the present time fixed points have been selected, convenient to the laboratory, for the study of the variations in the rhythm of hydro- logical gradients, particularly in order to study ascending currents at the edge of the continental shelf and the distribution in coastal waters of the fresh and brackish water brought down by the Nhatrang River. 193 7—Pac. Congress In collaboration with the study of fauna and biogeography outlined below, physical oceanography studies will be completed by pH measure- ments, estimation of dissolved oxygen, &c., and in general by a more detailed analysis of the various physical and chemical factors of sea-water. In the same way the study of the sea-bottom will not be confined to taking samples of the material of the ‘sea-bottom, but will include systematic study of the samples; classification of sands by granulometry, pH of muds, and so on. STUDY OF THE SEA—BOTTOM Up to the present the numerous samples taken for study of sedi- mentation and of the characteristics of the sea-bottom apart from the collection of samples of fauna have not all been fully used. Although some of the material has already been assembled, the preparation of a chart showing the nature of the sea-bottom in the coastal zone of Indo- China is a task still to be undertaken. A chart already published of trawling bottoms has given some useful information for the fishing industry. Co-ordination of this work, which is at present in progress, will make it possible to draw up a new working programme showing the gaps to be filled, particularly as regards improving our knowledge of fishing bottoms. In a related field observations are to be resumed of the under-water relief of the coast-line (study of the submarine valley of Mekong, and study of the old continental relationship between Indo-China and the Netherlands Indies). Also soundings are to be taken at certain points at present very little known (such soundings have previously enabled corrections to be made to charts of the Spartly Archipelago). BIOLOGICAL OCEANOGRAPHY Continuing the plankton fishing by day and by night which has been regularly undertaken: since 1936, nearly one thousand takings of plankton were made between 1939 and 1942. The general results of sorting are now in course of publication. The collections thus made have not yet all been studied. Some, however, have already formed the subject of publications, and Professor Fage’s study on Cumacea illustrates their interest. (A paper for presentation to the Congress gives a deeper insight into the working of this section of the laboratory.) FAUNAL STUDIES One of the principal activities of the Oceanographic Institute of Indo- China is the preparation of an inventory of the marine fauna of Indo- China by the establishment of collections. These suffered a great deal at the hands of pillagers during the war period. The establishment of a museum for the systematic classification of these collections is now in progress. So far, the collection of fishes made by Drs. Chevey and Durand has been reconstructed ; it contains over nine hundred species (about four thousand specimens). The collection of Coelenterata has not yet been resumed, but those consisting of molluscs and crustacea have been considerably enlarged : more than ten thousand specimens are listed, belonging to about eight hundred different species. It would be premature to make any general 194 estimate of the value of these collections: The study of a group of Crustacea (the Stomatopods) which is the subject of a paper before this Congress is, however, indicative of their interest. Bee | FISHING TECHNOLOGY In addition to an aquarium and museum open to the public the Oceanographic Institute of Indo-China has an office dealing with information relating to fishing, in connection’ with the studies of a technological laboratory. This office, established in 1938, assumed during the period 1940-1945 so great an importance, owing to the economic situation, that from 1943 to 1945 it engaged all the activities of the laboratory, which lost all scientific character. Resuming its proper role, it is particularly con- cerned with the study of fishing problems, in relation to the biology of seasonal migrating species (increase in: production), and to those techniques which may bring about better utilization of the products of the fishing industry. It plays the part of technical adviser to the various Governments associated in the Indo-China Union on maritime fishing questions. OCEANOGRAPHY OF JAPAN SINCE 1939 By Koji Hipaxa, Tokyo INTRODUCTION AcTIvitigs of physical oceanography in Japan. were largely curtailed by the World War II, especially at the close of the Pacific theatre. It can be said, therefore, that the ten years from the Sixth Pacific Science Congress to the Seventh is the period in which we made little progress in this branch of science. A summary of the official and personal activities in various institutions and agencies is now reviewed. ACTIVITIES IN THE HYDROGRAPHIC OFFICE, ToKYO In the Hydrographic Office, Tokyo, 103 hydrographic expeditions have been carried out from 1939 up to present in the Kuroshio region, Oyashio area, Equatorial Pacific, Yellow Sea, East China Sea, South China Sea, Okhotsk Sea, Bering Sea, Japan Sea, and other areas. Observations of tidal currents for periods of thirty days have been made at more than ten stations in bays and the Inland Sea. Temporary tidal observations were also made at nine coastal stations. After the end of the war this office was directed by Dr. Kwanji Suda, a physical ocean- ographer. The surveying vessels now in use are M.S. “ Kaiyo No. 4,” ' Katyo No. 5,” and “ Tenkai No. 1.” In 1940, Dr. S. Kishindo discussed the deep-sea temperatures and abyssal water movement in the Pacific Ocean, using the deep-sea obser- vations of the “ Komahashi,” which he directed as captain, and of other surveying ships. He made a vertical section of the Pacific, showing the distribution of temperature, salinity and oxygen, extending from the Bering Sea to the Antarctic Continent, use being made of all the available data of “ Carnegie,’ “ Dana,’ and “ Discovery II,” as well as of the Japanese surveying ships for the southern hemisphere. In the same year S. Kuwahara published a table of corrections on the density of sea-water for the sonic depths. He also reported on sonic sounding in 1943. 195 Dr. Koji Fukutomi has long been engaged in hydrographic obser- vations, constructing in 1945 diagrams for facilitating the use of non- protected deep-sea reversing thermometers, and made in the same year the determination of pressure coefficients of this type of thermometer by a specially devised apparatus. He afterward got a new post in the Hokkaido University and is now working there as a professor. Kaoru Yamashita has made some important contributions to the reduction of hydrographic data, constructing in 1945 diagrams for com- puting specific volume and dynamic elements. In 1947 M. Nakamiya discussed the hydrographic conditions in the Tsusima Current. He is now an able oceanographer and has many contributions to the hydrography of the adjacent seas of this country. Recently he was engaged in the study. of the isolated cold water off the south coast of Japan. ACTIVITIES IN. THE GOVERNMENT FISHERIES EXPERIMENTAL STATION The Government Fisheries Experimental Station, Tokyo, has long contributed to the hydrographic surveys chiefly with the surveying ship “Soyo Maru.’ The marine research of this organization is now mainly directed by Dr. Kinosuke Kimura, a physical oceanographer. In 1939 M. Uda and T. Yamashita made a series of experiments on the accuracy of density measurement by means of an Akanuma’s hydro- meter, which is sometimes used in Japan in place of chlorine titration. They showed that the accuracy is not good enough, but use is made when the chlorine titration is not available for some economic reasons. In 1940 Uda described in detail the hydrographic abnormality in the Kuroshio region off the south coasts of this country, and discussed the nature and behaviour of the isolated cold water, and K. Kimura studied the hydrography in Suruga Bay, a little to the south-west of Tokyo. This year Y. Yamamura devised an optical apparatus for determining the colour of the sea. M. Igarashi examined the variation of the surface salinity due to the rainfall in Kominato Bay, at the northern part of Honshu. In 1941 Uda discussed the hydrography in the East China Sea in detail. In 1942 K. Kimura published an intensive investigation on the phenomenon of the Kuroshio water mass frequently approaching towards the coasts. This: phenomenon was shown to occur everywhere on the coasts washed by this ocean current with cycles of a half month, one month, and two months, and is considered to depend on the minor fluctua- tions of this gigantic river in the ocean. During the period from 1943 to 1944 very few contributions were made to physical oceanography in the branch of fisheries. In 1945 Kimura examined the results of drift-bottle experiments formerly carried out in Japan Sea and interpreted the current system of this sea. After the end of the war the activities fell for a while, but rose rapidly in 1947. In the Government Fisheries Experimental Station, now directed by S. M. Tauti, K. Kimura pointed out the abnormally cold water along the Pacific coast in Boso Peninsula, to the east of Tokyo, and studied the results of drift bottle experiments carried out in that summer in Japan Sea. He also described an interesting movement of drift bottles 196 and current drags set adrift in Suruga Bay, showing a counter-clockwise circulation in the bay induced by the Kuroshio water mass. He also determined the current system in this bay from the drift of set-nets. In 1947 K. Kimura made an interpretation of the formation of isolated cold-water masses to the southern coasts of this country. Yasukazu Saito, a young research member working with Kimura, also determined the movement of water in the Tsusima Current from the result of drift-bottle experiments. He also published a theoretical research on the wind currents in limited seas, and the oscillations of lake water induced by winds. I. Yamanaka, working also with Kimura, published a report on the remarkable fluctuations of water temperature in Toyama Bay in the autumnal season. In the Government Fisheries Institute, Professor M. Okada published some remarks on the use of isopycnal charts for calculating ocean currents. He also published a method of determining the currents in the sea, using the principle of continuity of water volume, salinity, and other properties of sea-water. He was an eminent theoretical investigator on the dynamical oceanography,. but unfortunately Okada died in 1941 at the age of thirty-nine years. ACTIVITIES IN THE KOBE MARINE OBSERVATORY Since the Kobe Marine Observatory was established nearly thirty years ago, and has long tradition and numerous contributions to the science of the sea, it appears to the compiler natural to describe its activities separately from those of the other agencies subordinate to the Director of the Central Meteorological Observatory. The practical studies on ocean waves have been made by Koji Hidaka, Z. Yasui, and collaborators from 1937 on, the results being published from time to time. In 1939 Hidaka published the results of study of ocean waves and swells by the stereophotogrammetric survey, using a pair of cameras specially mounted on 6-metre base-line. The survey was made at several parts of the Pacific Ocean in the past four years. He deduced some empirical formulas with respect to the relations between winds and waves from the result of this survey. In 1939 K. Koenuma published his extensive studies on the Kuroshio, the Japan Current, chiefly consisting of water mass analysis and dis- cussion of the hydrography of this current. This paper was afterwards succeeded by a series of important papers on the hydrography of the western North Pacific. In 1939 K. Hidaka discussed how to select the layers of observations in hydrographical surveys, and showed that the number of layers of observation must be increased in depths shallower than 100m. This year he proposed a method of calculating the absolute velocity in dynamical calculation given by Bjerknes, use being made of the continuity of water volume and of salinity. In 1941 Z. Yasui computed the annual variation of water temperature and density along the coasts of Japan, and computed the amplitudes and phases for them. In March, 1942, K. Hidaka left the Kobe Marine Observatory and was transferred to the Tokyo University as a professor of Physical Oceano- graphy. The then Director Horiguti also left this observatory, and Dr. M. Uda was transferred from the Government Fisheries Experimental Station as a new Director: By Y. Matsudaira discussed in the same year the influence of hydrographic conditions of the North Pacific upon the climate of Japan and tried the long-range forecasting. In the same year Yukimasa Saito published a short note on the tidal currents in the Fukuoka Bay. In 1943 Uda discussed the accuracy of the oceanographical observa- tions in this country. He also discussed the fusion of icebergs rather theoretically. Yasui examined the annual rise and fall of the sea-level - in the Inland Sea derived from the variation of density. He also made several investigations on the scales of ocean waves and winds over the sea. In the same year Uda and H. Arakawa discussed the relation between hydrographic conditions and movement of depressions near Japan. In the fall of 1943 Uda was called for military service, and Dr. T. Sano succeeded him as the Director. Sano, who was a meteorologist, made little contribution to oceanography. He died prior to taking up his duties in March, 1945, and Yasuo Matsudaira succeeded to the directorship. In 1944 Z. Yasui published two papers on the tidal currents and the manceuvring of ships. In the same year Yukimasa Saito published an important paper on the calculation of vertical stability in the sea from the dynamical consideration starting from Lagrangian equations. The results of computation are practically unaltered, but the process is much simpler than the older one. He also published a theory of evapora- tion from the surface of the sea, and that of the stability oscillations of water in the sea. Recently Saito completed an extensive theoretical research on Oyashio, or the Kurile Current, partly consisting of water mass anaylsis, He also solved the differential equation giving the simultaneous effect of both horizontal and vertical mixing and showed that at a great distance from the sources the horizontal mixing could be neglected. T. Itiye, who, too, works in this observatory, is also a very eminent young hydrodynamician, completed a new theory of tsunami waves in 1948. He attributes the tsunami to a non-stationary disturbance. Itiye also showed that when a solitary wave propagating through a uniform channel passes by a narrower part it is divided into a train of waves. ACTIVITIES OF THE CENTRAL METEOROLOGICAL OBSERVATORY AND MARINE OBSERVATORIES The Marine Section of the Central. Meteorological Observatory was opened in 1942, the first chief being K. Tsukada, who was afterwards succeeded in 1944 by K. Hidaka, Professor of Physical Oceanography of the Tokyo University. He has been a concurrent member since he was transferred from Kobe in 1942. Prior to this period we have some contributions in this Observatory. In 1941 M. Hayakawa, of the Osaka Meteorological Observatory, published a series of results of model experiments on tsunami and ocean waves. In 1942 H. Arakawa, of the Central Meteorological Observatory, discussed the short-period irregularities observed in the water temperature in lakes and seas, ascribing their origin to the stability oscillations of water layers as suggested by IT. Hesselberg some ten years before. 198 In 1942 a marine observatory was established in Hakodate, Hokkaido, in addition to the Kobe Marine Observatory, whose activities were already described. The first director was Dr. Mashito Nakano, who was afterwards transferred to the Central Meteorological Observatory, Tokyo, in 1947. As soon as Nakano arrived at his new post in, Hakodate he planned the oceanic researches of the Tsugaru Straits between Japan Proper and Hokkaido, Volcanic Bay, and so forth, nearly all these plans having been realized up to the present. He also collected information on sea ice tin the Okhotsk and adjacent sea with some results. As soon as the war came to an end two more marine observatories were added, one being installed in Nagasaki under the directorship of Dr. M. Uda, and the other at Maizuru, on the Japan sea coast, under the directorship of Dr. D. Nishimura. Thus there are in all five marine organizations belonging to the Central Meteorological Observatory. At the end of 1943 the investigation on the relationship between the propagation of acoustic waves through sea-water and the hydrographic conditions was carried out by the members of the Central Meteorological Observatory, Tokyo. The experiments were carried out in Enoura Bay, near Numazu, and in lakes, with some reasonable results. Afterwards the field-work was chiefly carried out by Y. Takenouti, who constructed the distribution maps of acoustic audibility in the adjacent seas of Japan. The Kobe Marine Observatory also took part in this work, Y. Matsudaira and Yukimasa Saito being the chief personnel engaged in the practical work. The surf prediction was also studied in the Central Meteorological Observatory, on the principle that surfs depend upon the winds and coastal configuration, the observations being carried out in. several coasts from 1943 on, mainly near Tokyo. The results were, however, not complete before the end of the war. The observations were made by the members of the Marine Section of the Observatory, the results being studied by Y. Takenouti, N. Watanabe, and other collaborators. Y. Miyake in 1944 published an investigation on the bubbles of sea- water, showing that the salinity increases the stability of bubbles—that is, bubbles are apt to persist in a salter water than in a fresher. He now directs a tiny marine station at Jogashima Island, at the mouth of the Tokyo Bay, chemical oceanography being the main contribution. Mashito Nakano, who was in the Central Meteorological Observatory, Tokyo, published in 1939 a research on the secondary undulations of tides caused by cyclonic storms. He also explained the short-period sea- level fluctuations (one to three minutes) as a sort of swell emitted from the centres of these depressions. He published a monograph on tidal prediction in 1940. In 1942 he was appointed the Director of the newly built Hakodate Marine Observatory. Nakano has long been engaged in an intensive research on the effect of prevailing winds upon the depth of bays. This investigation is still continued, the seventh report having appeared in 1947. This year he was called back to Tokyo and worked at the Marine Section of the Central Meteorological Observatory in charge of tidal and oceanic researches. In the same year he also published a remark on the paper of J. Goldberg on the computation of free oscillations in bays. 199 In 1948 Hidaka resigned from the chief of the Marine Section, and M. Nakano succeeded his post. Hidaka is now a General Advisor to the Central Meteorological Observatory. Y. Takenouti, formerly working in the Marine Section of the Central Meteorological Observatory, succeeded M. Nakano and became the Director of the Hakodate Marine Observatory in 1947. He, too, is an able oceanographer and now engaged in the exploration of the sea in the northern part of this country. He has many contributions to the penetration of light through the sea-water, and derived the extinction coefficients for the water in the adjacent seas and lakes of Japan. S. Seki has long been engaged in tidal researches, and published the harmonic tidal constants at many ports along the coast of this country, computed by Tidal Institute method devised by Dr. A. T. Doodson. N. Watanabe was long engaged in the hydrographic surveys in the Marine Section of the Central Meteorological Observatory, and. has written several comments on the observations of surfs and waves. J. Sugiura, M. Koizumi, and J. Fukuoka, of the same agency are young observers engaged in the hydrographic work. Dr. M. Uda, who has long engaged in a series of hydrographic researches, was on active service during the war. He came back in the fall of 1945, and is now the director of the Nagasaki Marine Observatory. In 1947 he published a paper on the damage by ocean waves, especially by swells. His recent main contributions are, however, the hydrographic studies, the hydrographic conditions as the symptoms of weather change, the unusual hydrographic conditions in 1941 and 1942 prevailing over the sea to the east of the coasts, fluctuations of Tsusima Current, turbidity in the adjacent sea of Kyushu, and the discussion of the hydrography of the East China Sea, being the chief work appearing in this year. He has also been engaged in the studies of the Kuroshio, or the Japan Current, and related current system in the western Japan. His theory of the isolated cold water off the southern coasts of Japan should be especially noted. His observatory is now very active and publishes synoptic charts of the adjacent seas of Kyushu and south-western part of the Japan Sea, the harbour charts and many useful pamphlets for navigation, fisheries, and others. It has a surveying ship of about 100 tons and a small motor- boat. Oceanographic surveys in the sea adjacent to Kyushu are now being made actively. At the Maizuru Marine Observatory the study in physical oceano- graphy is not active now. It has a surveying ship about 100 tons, and a small motor-boat. M. Miyazaki, a young physical oceanographer, published a method of locating the motionless layer in the ocean. The validity of his procedure is not necessarily universally acceptable at present ; still a very hopeful future development is expected. ACTIVITIES IN THE KyorTo UNIVERSITY The activities in the Kyoto Imperial University is remarkable in these ten years. T. Nomitsu and T. Takegami in 1939 made a series of researches concerning the deep-sea deposits. They examined the influence of salts dissolved in sea-water upon the precipitation of small particles suspended, and explained the strip-like multiple-layer suspension 200 of mud particles. In the same year Nomitsu and G. Okamoto examined the condition under which the oscillation of water can occur on a shelf, and Nomitsu and K. Seno made a series of experiments on the formation of black cosmic dusts found in deep-sea deposits, and showed that such spherules can be formed by dropping fused metal balls into the water. This year Nomitsu and T. Matsuzaki published an investigation of the abnormally high sea-level accompanying the Muroto Typhoon in September, 1934. G. Okamoto made a theoretical research, on the river tides. A very interesting work of Nomitsu in this year is, however, that of the effect ofs mid-ocean pressure disturbance on the coastal hydrographical conditions. He and T. Hattori explained the abnormal fluctuations of water temperature and salinity in the Osaki Bay as the effects of disturbances propagated from the centre of cyclones or typhoons far to the south, thus enabling us to forecast the approach of the storm in some measure. Nomitsu also studied the relation between the hydro- graphic conditions and the run-off of the submarine hot springs in the Beppu Bay. : In the next year, 1940, no appreciable activity is seen from Kyoto. In 1941 Nomitsu and S. Otsuka examined the heavy water in the sea and showed that this can be used as an identifying property between different water masses. Momitsu also published a paper dealing with the polytropic atmosphere and ocean, the coefficient of eddy - viscosity differing in different directions. . By this supposition he could show that the angle between the steady wind and steady drift currents induced by the former is less than 45°, a result which V. W. Ekman got for an iso- tropic ocean. He also studied along with Yasukazu Saito the phenomena of freezing of sea water theoretically. In 1942 G. Okamoto discussed the drift currents in a polytropic ocean considered by Nomitsu in the preceding year. Nomitsu, Yasukasu Saito, and H. Tamura made experiments on the possible formation of sand-banks on the bottom, as the effect of stationary water movement such as secondary undulations of oceanic tides. They also gave some suggestions on the formation of sand ripples. A very wide gap lies from 1942 to 1945 in which we see scarcely any activity in Kyoto. In 1945, K. Seno published a consideration on the water movement on the bottom of the Pacific, and through the Bosphorus and Dardanelles Straits. Very unfortunately Professor T. Nomitsu, who has been very active and guided the researches of younger scientists in his university, died in 1946 on account of an accident. He was sixty-two years of age. We hereby express our deep mourning for his death and pay respect to his great achievement in every branch of geophysics. S. Hayami, a former research member in the Shanghai Institute for the Natural Researches, succeeded to his position. Recently Hayami, with T. Takegami, made some theoretical studies on the turbulence and convection in the uppermost layers of the ocean. M. Ishibashi, Professor of Kyoto University, has much interest in chemistry of sea-water and has many contributions in this domain of oceanography. 201 ACTIVITIES IN THE. lOKYO UNIVERSITY In 1942 Koji Hidaka, who has been working at Kobe for sixteen years, was appointed the professor of the Tokyo Imperial University and has given ever since the lectures on physical oceanography in the faculties of science. In 1943 Hidaka gave a theoretical investigation on the motion of water in an enclosed sea rotating with the earth, showing that an external force can produce the same motion from the surface down to the bottom. Similar attempt was tried in case of wind currents in a viscous water, but T. Itiye showed the solution is not possible. ~ In 1943 Hidaka showed that the stream lines in the two-dimensional wind circulation in a lake can be compared to the buckling of elastic plates built in along the portion corresponding to the bottom, while. a movement is applied on the remaining straight portion corresponding to the wind-driven surface of a lake. This theory was satisfactorily proved by later experiments with steel plates. In 1944 Hidaka published his results of calculation on the develop- ment of surface slope and currents in an enclosed sea induced by winds, use being made of a pair of simultaneous integral equations of Volterra type. In 1945 Hidaka tried to use the non-protected reversing thermometer for shallower seas and lakes. For this purpose it was necessary to construct a thermometer with pressure coefficient about ten times as large as those hitherto used. S. Watanabe actually constructed this. The observations were made in Tokyo Bay with some results. In nearly the same year R. Takahashi, of the Earthquake Research ~ Institute, Tokyo University, published a series of important theoretical investigations on the destructive sea waves, or tsunami. He studied the nature of oscillations responsible for the possible sources assumed on the bottom of the sea. In 1948 he discussed the occurrence of tsunami waves by a travelling disturbance on the floor of the ocean. In 1945 Hidaka devised a method of integrating the differential equations of drift current, being based on Y. Takahashi’s idea. This method can be applied to the case of wind stress varying with time. He examined the method of location of motionless layer in the sea and concluded in 1946 that the motionless layer corresponds to the depth where the second vertical space gradient of salinity vanishes. After- ward M. Miyazaki in 1946 derived a similar conclusion together with the method of location of these layers. Hidaka is now studying a qualitative analysis of tides in which he hopes to separate the influences of sun, moon, and meteorological effects distinctly, analysis being made on the tide heights as the functions of the hour angles and distances to the earth of the sun and moon. This seems unsuitable to the prediction, because the mechanical operation appears to be very difficult. in 1947 Hidaka and S. Hikozaka applied J. Proudman’s theory of diffraction of tidal waves to the distribution of 1946 tsunami height alond the coast of Kauai Island, Hawaii, which is approximately circular in form. } Kozo Yoshida has been showing activities from 1944 on in the practical study of ocean waves and surfs as well as the theoretical investi- gations of long and surface waves, notably his investigation on the 202 reflection and other related behaviours of long waves at a discontinuity in the section of a canal. He is now engaged in the theoretical proof - of Borgén’s formula. K. Kajiura made some investigations on the hydrography of Okhotsk Sea in 1948. Hidaka and T. Suzuki are planning the stereophoto- grammetric study of surfs and breakers. They, too, examined the secular fluctuations of the Tsushima Currents from those of the inclinations of thermocline. ACTIVITIES IN OTHER UNIVERSITIES AND COLLEGES In 1940 N. Inoue, who was then teaching in the Hakodate Fisheries College, discussed the short-period temperature oscillations observed in coastal waters. In 1941 N. Obara, of the Tokyo Bunrika University, published a paper on the course of flow of river water poured into Shimoda Bay, a little to the south-west of Tokyo. Hikoji Yamada, of the Kyushu University, has long been engaged in the theoretical researches of wind-driven water accumulated along the coast. He derived in 1945 several important results which will contribute greatly to the future investigations of allied phenomena. Koji Fukutomi, Professor of Hokkaido University, -published in 1947 a series of original papers on the formation and behaviour of sea ces M. Hatanaka, of the Onagawa Marine Chemical Laboratory, belong- ing to the Tohoku University, Sendai, examined in 1947 the secular variations of the water temperature along our coasts, use being made of about forty years of coastal temperature observations. He concluded that there is a distinct cycle of about eleven years, probably correspond- ing to the cycle of solar activity. The Tohoku University has a Marine Biological Station at Asamushi, near Aomori. Dr. Seiji Kobubo in this station is an able marine bio- logical oceanographer, making hydrographic surveys in the Aomori Bay several times a year and publishing the results in a monthly pamphlet with the assistance of T. Kawamura. PRESENT STATUS OF THE OCEANIC OBSERVATIONS AND RESEARCHES IN JAPAN The hydrographic observations in our adjacent seas are now being carried out very frequently, under the control of the U.S. Occupational Forces, with the surveying ships of the Hydrographic Office, Central Meteorological Observatory, including four marine observatories and the Government Fisheries Experimental Station, and the local agencies sub- ordinate to them. The elements observed range almost in every branch of physical, chemical, biological, and geological oceanography. Activities, largely suppressed during the war, are now showing rapid recovery. Still the facilities and apparatus are so inadequate that the observations are mostly confined to the layers shallower than 1,000 to 1,500m. It is very urgent that the equipment should be improved so as to make it possible to make observations in all layers from the surface down to the bottom. Research in oceanography is being carried on in the Tokyo, Kyoto, -and Hokkaido Universities, and the Government Fisheries Institute has several research members, too. 203 Fixed point observations were also commenced in the fall of 1947, - and some hydrographic observations are being made at a fixed station 39° N., 153° E. and on the way to and from this point, this being carried out by the request of U.S. Forces for the protection of air ways. The administration for these observations is made in the Central Meteo- rological Observatory, use being made of four ships for this purpose. These government agencies meet in conferences several times every year, the representative members showing each other the results of the observations and expeditions carried out, and discussing the areas to be explored by different agencies in subsequent expeditions. STANDARD SEA-WATER Towards 1940 the standard sea-water furnished by Professor Knudsen became very scarce in this country, while its importation was limited by government policy. It was therefore very difficult to carry out further salinity determination, and some alternative proved necessary. For this reason a committee met in the National Research Council of Japan for preparing standard sea-water in this country. The first meeting was held in November, 1940, in Tokyo, and the programme of preparing the standard sea-water was decided. The procedure was twofold. The secondary standard was prepared from the natural sea-water. The primary standard or Urnormal is the sea-water whose chlorinity is determined with reference to the atomic weight silver, so the preparation of atomic weight silver was a first consideration. The preparation of pure silver was referred to Professor M. Ishibashi, but 1t has not been prepared as yet. The sampling of sea-water was made at the point 25° 00’ N. 143° 40’ E., about 100 miles south of Titizima Island, Bonin Group. The sea-water taken was increased in concentration by heating so as to have nearly the same salinity as that of Professor Knudsen—that is, about 19-4 per mille. As to the details about the subsequent processes, we have the report of Dr. Y. Miyake, the chemical oceanographer then in charge of preparation. The second sampling was made after the outbreak of the war in 1943, the third after the end of the war in 1947, the sampling being, of course, made near the coasts of Japanese Islands. As is very natural the standard sea-water must be a universally accepted one, since the oceanography can be promoted only by an inter- national co-operation and data obtained must be of international standard for the accurate determination of salinity in the adjacent seas of this country depends upon whether our standard is accepted as reliable or not. For this reason, a comparison of our standard with those of Copenhagen and of Woods Hole is an urgent matter now, and in an assembly of leading Japanese oceanographers in June, 1948, K. Kimura and K. Hidaka suggested that several ampuras of our standard should be sent to America and be tested there for comparison. Dr. T. Yamamoto, the chief of the committee on the preparation of standard sea-water, made some titrations of our standard, using the standard sea-water of Copenhagen and of Woods Hole, kindly furnished recently by American oceanographers by the courtesy of the U.S. Hydrographic Office, Tokyo Branch. He made an oral report then on the result of titration that the agreement was satisfactory, the value of chlorinity of our standard coinciding with those of Copenhagen and Woods Hole to within 0:01 per mille. For the exploration of the Pacific in future there must not be discrepancies in 204 the determination of chlorinity between America and Japan, It is, the compiler believes, very important for us to pay attention to this point for the future exploration of the Pacific oceanography. At present the leading chemists engaged in the preparation of standard sea-water are, besides Yamamoto, Y. Miyake and K. Tanii, K. Suda, K. Kimura, and K. Hidaka, who is greatly interested in this work. DEEP-SEA REVERSING [THERMOMETER Imported deep-sea reversing thermometers of Richter-Wiese make also became very scarce in this country towards the outbreak of the war, Shichiro Watabe, however, a very skilled thermometer maker, made thousands of them for the hydrographic survey of this country. He can prepare both protected and non-protected at present. Of course, the performance is not so good as those of Richter-Wiese, or of Negretti- Zambra. An encouragement by enthusiastic oceanographers, both home and abroad, will improve the function. Watabe remarked to the compiler that Dr. T. G. Thompson, of Seattle, was much interested in his deep-sea thermometers. At present K. Hidaka is planning a non-protected thermometer for shallow waters. For this purpose, the pressure coefficient must be magnified several times that of the present model. He hopes this kind of thermometer may be tried in foreign countries. THE OCEANOGRAPHICAL SOCIETY OF JAPAN This scientific society was established in January, 1941, with Dr. T. Okada as the President. It has issued a popular monthly magazine Katyo no Kagaku (Science of the Sea) and Journal of the Oceanographical Society of Japan (quarterly purely scientific journal), both in Japanese language. Both were suspended by the war after 1944, but we are now preparing for active publication in the future. Dr. Okada resigned this year, and K. Hidaka is now president. A committee on oceanographic research was established in 1943 in the Japan Society of Promotion of Scientific Research for the purpose of scientific exploration of the sea. It consisted of about 30 leading physical, chemical, and geological oceanographers but was disbanded in 1946 for economical reasons. ANTARCTIC OBSERVATIONS The Japanese Antarctic whaling cruises were resumed for the winters 1946-47 and 1947-48, and specialists were allowed to take part in these expeditions for scientific investigations. During the cruise of the winter 1946-47, T. Shimomura, of the Central Meteorological Observatory took part in the expedition, and obtained oceanographic data, although the results are not yet published. On the second cruise of the winter 1947-48 Dr. T. Tamura, professor of the Hakodate Fisheries College and the concurrent member of the Hakodate Marine Observatory, and J. Sugiura, 2 young physical oceano- grapher of the Central Meteorological Observatory, pushed into the Antarctic circle on board a whaler, as far as 75° 41’S. and got many oceanic data from the layers down to 400 m., the measurements being made of the water temperatures, salinity, hydrogen-ion concentration, oxygen, silicates, phosphates, colour of the sea, and transparency. Meteorological and biological data were taken, too. 205 BIBLIOGRAPHY (1) Upa, M. and Imamura, K. (1938): Hydrographic Bulletin, No. 17. (2) Tayama, R. (1939): Terraces of the South Sea Islands Under the Japanese Sea Islands. Jour. Geol. Soc. Japan, Vol. 46, No. 549. (3) (1939): Correlation of the Geological Structure of the South Sea Islands. Jour. Geol. Soc. Japan, Vol. 46, No. 549. (4) ——— (1939): Distribution of Coral-Reefs. Geogr. Rev. Japan, Vol. 16, No. 6. (5) — (1939): Coral-Reefs. Hydrographic Bulletin, Nos. 10-11. (6) (1940): Geology, Geomorphology, and Coral Reefs of Truk Islands. Jubilee Publ. Comm, Prof. H. Yabe, Sixtieth Birthday, Vol. 1. (7) Asano, K. (1942): On the Coral Reefs of the South Sea Islands. Contri. Inst. Geol. Pal., Tohoku Univ., in Japanese, No. 39. (8) YasuHaRaA, Y. and Ucuiumti, R. (1942): Investigations in the Kainan-t0o Seas. Fish. Exp. Sta. of Gov. Gen. of Taiwan (Formosa), No. 25. (9) YosHimurRA, S. (1943): Bottom Configuration of the Philippine Islands. Jour. Ocean. Soc. Japan, Vol. 3, No. 2. (10) Onara, S. (1942): Oceanographic Investigations of the South-western Pacific. Rep. of East Asiatic Inst., No. 307. (11) Hydrographic Section: Report of Investigations of the Great South Sea Earthquake of 1946 (1948): Spec. Publ. of Hydrographic Bulletin, (12) Hamacucui, H. (1938): Chemical Investigations of Deep Sea Muds. Jour. Chemical Soc. Japan, No. 59. (13) SHoj1, S. (1940): Investigations of the Deep Sea Deposits of South-western North Pacific Ocean. Jubilee Publ. Com. Prof. H. Yabe, Sixtieth Birthday, Vol. 2. (14) SuzuxKi, K. and Sato, A. (1944): On the Bottom Deposits in the Vicinity of Izu Peninsula. Jour. Ocean. Soc. Japan, Vol. 3, No. 2. (15) Nuno, H. (1946): Distribution of Organisms on Banks at the Mouth of Wakasa Bay, Japan Sea and Adjoining Continental Shelf. Rep. Comm. Marine Ecol., Washington, No. 6. (16) (1943): Distribution of Gravels and Foundation Rocks on the Sea Bottom at the Southern Part of Kamtshatka and the Kurile Islands. Jour. Ocean. Soc. Japan, Vol. 2, No. 4. (17) — (1944): On the Bottom Deposits in the Neighbouring Seas of Kam- tchatka Peninsula and the Kurile Islands. Rep. Sci. Invest. North Chishima 635, IN@s Ie (18) Hapa, Y. (1943) : On the Foraminiferal Communities and Bottom Deposits of the Java Sea. Jour. Ocean. Soc. Japan, Vol. 2, No. 4. (19) Masur (1943): On the Bottom Communities of Toyko Bay. Jour. Ocean. Soc. Japan, Vol. 3, No. 2. (20) Miyayr, D. (1942): On the Bottom Communities of Nanao Bay. Jour. Ocean. Soc. Japan, Vol. 2, No. 1. (21) Mivaj1, D. and Hae, T. (1947): “On .Thanatoccenoses”’ of Bays. Phy- stology and Ecology, Vol. 1, No. 2. (22) Nuo, H. (1938): Bottom Deposits of the Kinshu Bankin Suruga Bay. Jour. Geol. Soc. Japan, Vol. 45, No. 540. (23) (1939): Bottom Deposits of the Yomeguri Bank off the Coast of ; Noto Peninsula. Jour. Geol. Soc. Japan, Vol. 46, No. 550. 24) (1939): Soundings from Okinoyama Bank, Tokyo Bay. Jour. Geol. Soc. Japan, Vol. 46, No. 548. (25) (1940): The Geology, Topography, and Marine Deposits of Kyuro- kusima and Its Vicinity. Jubilee Publ. Comm. Prof. H. Yabe, Sixtieth Birth- day, Vol. 1. (26) (1943): Soundings from Nakanose Bank, Tokyo Bay. Rep. Adv. Sci. Soc. Japan, Vol. 1, No. 3. (27) (1944): On the Soundings of Oki Banks. Sigen Kagaku Kenkyujc, Nol liNose2: (28) (1938): Investigations on the Soundings of Drowned Valleys. Part 1: Valley Deposits’ in the Valley off Toyama Bay. Jour. Geol. Soc. Japan, Vol. 45, No. 542. 206 SYMPOSIUM ON UNDERWATER SOUND AND ITS BIOLOGICAL AND OCEANOGRAPHICAL APPLICATIONS SOUND AS A TOOL IN MARINE ECOLOGY, FROM DATA ON BIOLOGICAL SOUNDS AND THE DEEP SCATTERING LAYER(?*) By Martin W. JOHNSON, Scripps Institution of Oceanography, University of California [A bstract| Underwater sounds produced by animals or reflected by them can be used in studying concentrations and behaviour of certain marine populations. Biological Sounds.—Crustacea and fishes are the main sound producers, though whales and porpoises are also capable of making ‘sounds. Crustacean sounds consist mainly of high frequency crackle produced by snapping shrimp. The sound produced by a large population of these shrimp is continuous, and with directional sound equipment their habitats can be detected to distances of 2,000 yards or more. Studies of the continuity and sound spectrum level of shrimp gives evidence pertaining to stability of populations, their diurnal activities, geographical distribution, and type of bottom and depth of water preferred. Observations on fish noises have given less useful ecological data. They do, however, demonstrate a regular and pronounced seasonal and diurnal habit of certain Sciaenide to form localized choruses, as contrasted with isolated solos by the toadfish (Ofsanus tau) while guarding its nest or territory. Reflected Sounds.—The “ deep scattering layer ”’ (a sound scattering layer at 150 to 400 fathoms within the sea) was shown by its diurnal vertical migrations to be biological in nature. The partial reflection of fathometer signals in this layer promises to be a useful ecological tool in studying the distribution, concentration, and movements of the organisms involved in causing the scatter. While using sound as a guide, a preliminary study in 1945 showed a positive correlation with plankton stratification, especially the larger plankters, and the depth of the scattering layer. This relationship may be partly secondary, since the more effective scatterers may be larger forms that subsist upon and migrate more or or less concurrently with the plankton. SUMMARY OF DISCUSSION Dr. Tweedie inquired whether the mechanism of Cetacean noise production was known, and it was replied that little work had been done. Seals were known to produce an underwater noise sounding similar to that produced by aerial means, though doubtless produced in a different manner. As regards underwater vocal noises, it was observed that a yell is not discernible, but that a sustained humming vibration is able to be picked up. (4) 1948, Journal of Marine Research, Vol. 7, No. 3, pp. 443-458. - 207 Dr. Hubbs was inclined to attribute whale noises to movement of air back and forward in the lungs, and it was thought possible that they may at times exhale below the surface to produce a noise, although in ‘that case air bubbles would be observed accompanying the exhalation. Dr. Hiatt remarked that divers can communicate as far as 10 ft. away. It had previously been maintained that “ ship worms ”’ could be heard working in the hulls, but Dr. Johnson attributed this actually to Crangon shrimps. In answer to Dr. Hiatt, who inquired whether the high pitch whale note might be that of a calf. it was doubted whether calves were present with the school of hump-backs. Dr. Hubbs pointed out that it had been determined at Scripps that whales have obviously some means of communication. Many of these sounds were stated to be within human audible range, such as those of croaking fishes. Others, such as some of the crustacean sounds and the high frequency porpoise sounds, were outside the range of audibility. In fishes, sound is perhaps associated with the breeding cycle, sound-producing organs being confined in some cases to one sex only. Dr. Hubbs indicated that Silurid cat-fishes have stridulating organs on the pectorial spine. Mr. Powell raised the question of shell-fish noises on New Zealand estuaries. He stated that the clicking noises observed about dusk were perhaps attributable to cockles closing their valves suddenly. Dredgings over estuaries had indicated an absence of snapping shrimp. Dr. Johnson, however, discounted the theory that either oysters or cockles produced the noise, and Mr. Morton stated that on Auckland Harbour estuaries he has found by digging specimens of Crangon novae-zelandiae associated with cockles and producing a noise like the fall of hailstones. Dr. Hiatt inquired whether noises were produced by skin friction in swimming. No work had been done, but Dr. Johnson thought the effects would probably be of minor importance. Stream lining is well developed in fishes. Tail whipping and muscular movements might, however, produce sound. Dr. Hubbs cited the scarcely perceptible hum of Lepftocottus, and Dr. Johnson referred to that of grunt-fish and the small alligator fish. There was also cited the clicking sound made by some shore crabs in exuding bubbles from the mouth. Dr. Emery inquired whether perhaps sea mammals might make use of noises for echo ranging in the pursuit of fish. It was stated also that, on the inverse side, advantage might be taken of artificially produced noises or recordings to frighten away fish from specific localities during T.N.T. depth charge work, during which fish mortality was heavy. It was suggested, further, that fish might be attracted by the reproduction of suitable noises. Dr. Brunn gave an account of the detection of dolphin schools during the use of high-frequency echo-sounding apparatus. He stated that a school of 100 to 125 were observed smacking the water with their tails with great vigour. A discussion followed on the occurrence of auditory organs and sound receptors in fish. Dr. Brunn emphasized that fish are able to detect half-tones, as had been established by the production of conditioned reflexes in which a series of auditory effects differing by half-tones had been associated with disagreeable and palatable food substances. 208 - SYMPOSIUM ON SEDIMENTATION AND CHARACTERISTICS OF SEA BOTTOM IN THE PACIFIC BASIN SEDIMENT DISTRIBULION ON THE AST ASTATIC CONDINE NDA SHE EV IESG) By Francis P. SHEPARD, Scripps Institution of Oceanography, University of California (A bstract] During the war charts were prepared for the United States Navy showing the bottom character on the continental shelves along the eastern and south-eastern coasts of Asia. They are based on about four hundred thousand bottom notations’ from the most detailed Japanese, British, Dutch, and French charts which were available in the files of the Navy Hydrographic Office. The final charts were printed in smal] numbers by the Hydrographic Office. The charts show that sediment is distributed irregularly over the Asiatic continental shelves. In few places is there a graduation outward from coarse sediment to fine. Along much of the Asiatic coast mud predominates on the inner shelf, and sand outside. Large rock areas occur, particularly along the Japanese coast where the Kuroshio (Japanese Current) is flowing at a high speed. Rock notations are abundant on submerged hills, off rocky points, in narrow straits, and at ‘the outer edge of the shelves. Mud is found in enclosed bays, and sand is most common in broad open bays, although mud is present in the latter off some large rivers. Sand is the most common type of sediment reported from the Asiatic shelf. The distribution of the sediments is controlled by such factors as (1) sources (large rivers, shore erosion, organic growth, and recent vulcanism), (2) currents (oceanic, tidal, and longshore), (3) waves (on exposed points), (4) bottom topography (submerged hills, basins, and canyons). SUMMARY OF DISCUSSION Dr. Shepard’s results had tended to show that rock notations were encountered most commonly in straits and areas subject to great current sweep, sand on beaches with no large rivers entering, and on continental _ Shelves, and mud in river deposits, inner parts of shelves, and at the heads of submarine canyons. Mr. Powell, speaking of the results of a ten to fifteen years bottom survey of the Waitemata Harbour and Hauraki Gulf, was able to point to results exactly similar to the conclusions of Dr. Shepard. Coarse sedi- ments were found in the middle of the Auckland Harbour along the tidal current, and fine sediments from soft Tertiary mudstones at the sides. But in the case of the outer islands the normal distribution described in such localities by Dr. Shepard was likewise adhered to. Heavier material is tossed inshore, mud occurring in the deeper portions. It was pointed out by Mr. Powell that the hard bottom sediments in his area were purely (1) Shepard, F. P.; Emery, Kk. O.; and Gould, H. R. (1949): Allan Hancock Foundation Publications, Occ. Pap., No. 9, pp. 1-64. 209° organic in origin. There were no gravels, and animal shell remains them- selves build up the bottom substratum where the currents are greatest. The tongue of hard bottom deposits extends from the harbour out to North Head. There are also lens-shaped hard areas outside the harbour, amidst the mud, and these again are attributable to increasing current velocities. Dr. van Baren referred to detailed mapping of the Sunda Sea and the southern part of the China Sea. Sampling of the bottom had revealed, he claimed, hardly any connection between sea movements and bottom material. We might expect the east to west current strongly developed in the Java Sea to affect the distribution of sediments, but no such result was to be found. It was agreed that restudy of the area in light of Dr. Shepard’s conclusions would be valuable. Dr. Shepard asked whether it was not true that there was some amount of coarse material in the Sumatra-Java Strait. It was stated that muddy sediments predominate. Dr. Emery observed also that the sediments are probably. not all detrital, which would complicate the matter. Dr. Kuenen stated that the results tended to confirm that the classical grading with fine sediments outermost does not hold good on the conti- nental shelf. He asked whether waves with a churning action at higher velocity had been considered as well as slower-moving currents. It was answered that this had been thought of, and evidence was cited from California, where detailed work had been carried out on wave effects. The sediments off-shore were very coarse, as the depth was too great for wave action. A programme was under way at Scripps Institute on currents and waves at different depths. THE WHITE ISLAND TRENCH: A SUBMARINE GRABEN IN THE BAY OF PLENTY, NEW ZEALAND By C. A. Freminc, New Zealand Geological Survey AN expedition of the New Zealand Department of Scientific and Indus- trial Research to White Island in January, 1947, stimulated interest in the characters of the sea bottom adjacent to this active volcano. Isobaths drawn on Admiralty Chart No. 2527 revealed a well-defined trench (Fig. 1) extending north-east from the Bay of Plenty coast. The name “White Island Trench” is proposed for this steep walled depression which has a width of about 7 miles, measured from the summits of its walls, and a depth, below the general level of the continental shelf, of: about 3,000 ft. The trench can be traced clearly from the 75 fathom isobath to a depth of 850 fathoms at a point 15 miles north-east of White Island. This volcano rises to a height of 1,000 ft. on a ridge which ex- tends seawards from the Rurima Rocks, to delimit the west side of the trench. There is a fall of 5,000 ft. in 5 miles from the top of White Island to the bottom of the trench. Under such conditions in an area of active seismicity, submarine avalanches are likely, and may account for irregularities in the walls of the trench. Shorewards from the 75 fathom isobath, recent sediments doubtless obscure the trench, but its persistence to the south-south-west is attested by the known structure of the Whakatane district, where Macpherson (1944) has mapped a narrow graben occupied by the deep alluvium of 210 Scale in Miles BOOS VIO 5 1 iat 33 1 __s oO White Island @& a Rr X 222s 568 Rurima Rocks | Ss) Sos wae va MV hale Island De aay Legend Volcanoes Alluvium Faults I[sobaths in Fathoms ome JGB.P50 G.S 754 Fic. 1.—Map of part of the Bay of Plenty, North Island, New Zealand (see Fig. 2) showing White Island Trench. Isobaths (in fathoms) based on Admiralty Chart No. 2527. Position of faulted boundaries of Rangitaiki Graben after Macpherson (1944) 211 the Rangitaiki River, trending inland from Whakatane. Macpherson’s boundary faults are shown in Fig. 1. Geophysical work by Modriniak (1945) indicates that sediment fills the graben to a depth of at least 700 ft. It may be safely inferred that the White Island Trench is the seaward continuation of the Whakatane Graben. Available data do not permit detailed mapping of the sea bottom far beyond White Island. Nevertheless, what soundings there are (Fig. 2) suggest that the White Island trench has considerable extension to the north-north-east towards the Kermadec Islands. The soundings shown in Fig. 2 are too widely spaced to allow determination of the width of the trench over most of its length. The bottom of the trench remains at approximately 3,000 ft. below the adjacent sea-floor, and its greatest known depth below sea-level, 2,050 fathoms, at a point 140 miles south- west of Esperance Rock, constitutes the deepest part of the sea bottom between the East Cape-Kermadec Ridge to the east, and the Gazelle Basin to the west. The low ridge west of the trench suggests a structural “high ’’ which has no precise analogy in the known structure of the Bay of Plenty area. The relationships between the White Island Trench and other known structural lineaments are fairly obvious. It is parallel to the greater submarine welt and foredeep of the East Cape- Kermadec Ridge and Kermadec-Tonga Trough, and occupies the position of a “ back-deep ”’ on the inner side of these folds. It is homologous with the complex - volcano-tectonic depression of the North Island of New Zealand to which the name Taupo Graben is applied, and further work will probably show continuity. Still more clear is the relation of the submarine graben to the line of active and dormant volcanoes which Dieffenbach in 1843 recognized as “ one connected hearth of volcanic action.”’ REFERENCES MacrHerson, E. O. (1944): N.Z. Journ. Sci. & Tech., Vol. 26, No. 2, (Sec. B), pp. 66-76. Mopriniak, N. (1945): N.Z. Journ. Sci. & Tech., Vol: 26, No. 6, (Sec. B.), pp: 327-330. SUMMARY OF DISCUSSION Dr. Gutenberg emphasized that such ridges separated by troughs or grabens occurred very widely, and were not an isolated phenomenon. He instanced the island ridges of the East Indies separated by troughs. Other such regions were quite frequent in the Pacific, although their significance was rather obscure. Mr. Fleming agreed with the last speaker. He pointed out that the White Island trench was a collapse rather than a downfold, but agreed that as such it is by no means unprecedented. Dr. Kuenen maintained that the present example was important as illustrating a trench actually continuing into the continental shelf as a graben. Dr. Gutenberg considered that a gravity profile across such a ridge and trench would be very valuable, and Mr. Fleming indicated that a gravity meter was to be brought into use, if possible, this year. 212 ‘KERMADEC* AS ! ! i ' ! ! I I 1 My f Le 7 ) “Y if ( qe ve y 16 fa EL GS. 755 Fic. 2.—Generalized bottom topography north-east of North isiand, New Zealand. Tsobaths based on Admiralty Chart No. 788 213 SUMMARY OF THE RESEARCHES ON THE SUBMARINE CONFIGURATION AND BOTTOM DEPOSITS OF THE NEIGHBOURING SEAS OF JAPAN DURING 1939-1948 By Hrrosui Nino, Suisan, Koshusho, Japan A SUMMARY of the investigations on the submarine configuration and bottom deposits of the neighbouring seas of Japan during the period covering 1938-1940 is given here. Researches having been carried out extensively along various lines, only the outstanding results are presented. (1) SUBMARINE CONFIGURATION OF THE NEIGHBOURING SEAS OF JAPAN 1. General Configuration A. Pacific Ocean The increase in number of the sounding stations by the echo-sounding method has resulted in the necessity for revision of previous marine charts, and, consequently, a new chart is in the process of publication. Bathymetric charts (No. 6080 and others) of the neighbouring seas of Japan are being published by the Hydrographic Section of the Bureau of Transportation, and at present a new one for the Japanese coasts is now in press. According to this chart, the Japan Trench is narrower than indicated on previous charts, and a depth of 10,600 metres was sounded in it. The Mariana Trench comprises three parts, and the Caroline Oceanic Basin can be divided into two parts in east-to-west direction. The Yap ridge is a prolongation of the Mariana ridge, and the submarine ridge north of Palau continues to the Okino-tori-shima. The bottom configuration of the South Japan Sea (south-east of Shikoku) is complicated, there being many depressions, steep slopes, and, according to the Fisheries Experiment Station, there has been discovered a shallow area measuring 480 metres at 29° 51’ N. lat., 133° 21’ E. long, Concerning the coral reefs of the former Japanese mandated territory there are numerous reports, and it is now known that the foundations of them consist of the Tertiary or pre-Tertiary formations, whose ages have been determined by paleontological evidence. Among the coral-reefs there exists a peculiar type known as the Table reef. South China Sea.—Sounding investigations have revealed the exist- ence of a peculiar depression, measuring more than 70 metres in width, between Kainan-to and French Indo-China. Philippine Seas——The submarine configuration of the Philippine seas more resembles that of the East India Islands than the neigh- bouring seas of Japan. Submarine valleys are well developed along the south-eastern coast. Japan Sea.—According to the results of investigation of the Fisheries Experiment Station of the Hydrographic Section and of Korea, the submarine configuration of the Japan Sea is quite complicated in the southern half and in the central part there is the Yamato Bank (285 m.), North Yamato Bank (418m.), and north-west of the Oki Islands is the Oki Bank (275m.). Also, along the Japanese Islands, there exist many ridges. ; 214 Okhotsk Sea.—In the northern part of the Okhotsk Sea the conti- nental shelf is 50-100 metres deeper in comparison with other regions. This fact suggests that there must have been a relative change in sea-level. 2. Special Configuration A. Great Earthquakes and Submarine Configuration After the great earthquake of the South Sea at 4.19 a.m., on the 21st December, 1945, the sea area of Kishu and Shikoku was deepened about | metre in general. Also large-scale steep slopes were introduced to the submarine configuration in the vicinity of the epicentre. B. Submarine Valleys There are many submarine valleys along the Japanese coasts. The lower limit of the valleys extend beyond 1,000 metres depth, and the upper limit (shallower) is cut deeply in the continental shelf. Some of the valleys have their upper limit around 120 metres depth, while others are even shallower, sounding only 20 metres depth. The valleys are imbricate, with many branches (tributaries) cut into the continental shelf. C. Ridges and Banks Many ridges and banks have been found to be distributed near the continental shelf of the Japanese Islands. These ridges and banks are arranged roughly parallel to the coast of the Japan Sea and are provided with steep slopes with rather flat summits which measure only 120-140 metres in depth; these appear like tilted blocks. On the sea bottom are also found volcanic ridges; these are an extension of volcanic ranges on land. (2) Botrom DEposits. OF THE NEIGHBOURING SEAS OF JAPAN 1. Bottom Deposits in General A. Deep Sea Bottom Deposits It is interesting to know that an analysis of the deep sea mud collected by the Hydrographic Section proved the presence of radium and calcium. _B. Bottom Deposits of the Coasts Pacific Coast.—A survey of the bottom deposits in the vicinity of the Izu Peninsula shows that the rocks building the adjoining land have direct influence on the bottom deposits. Also a survey of the Wakasa Bay shows similar results, and, furthermore, the relation between the distribution of grain size and oceanic currents has been clarified. It may be said that the bottom deposits of coasts is closely related to crustal movement in the vicinity. Along the coast of Kamtchatka there is exposed a fossil-bearing bed rock at the depth of about 300 metres, and similar phenomenon also exist in the neighbouring seas of Japan down to considerable depths. Off the Kurile Islands are found rather extensive Diatom deposits. The relation between foraminiferal communites and bottom deposits has been studied in the Java Sea, and the relation between bottom animals and bottom deposits in enclosed bays has been studied in various parts of Japan. 215 2. Bottom Deposits of Regions with Special Submarine Configuration A. Bottom Deposits of Ridges and Banks There are ridges and banks believed to be a product of tectonic activity, and, leaving aside one case of foundation rocks, the others are built of fossil- bearing Tertiary sediments whose summits are covered with coarse- grained sand formation. Fine sand is distributed around the ridges to considerable depths. There are many such ridges and banks arranged parallel to the coast of the Japan Sea, while on the Pacific coast they have been recognized only at the mouths of the Suruga and Tosa bays. B. Bottom Deposits of Submarine Valleys The submarine valleys of the Japanese Seas are imbricate in pattern, with steep sides which expose fossiliferous Tertiary formations, and the valley wall of the submarine valley of Shikoku exposes Pleistocene rocks. Gravel and fine sand is distributed on the walls of the submarine valleys, while in the central parts are found muds. Judging from the grade distribution of the sand and mud in the vicinities of submarine valleys it appears that at present the valleys are being gradually filled by the action of oceanic currents. DKANSPORLATION SANDED EPO SMION MS Mei UieE iP iaiNe CURRENTS By Pu. H. KUENEN, Groningen, Holland [Abstract] Experiments by the author confirmed that water containing a load of sediment will flow under the influence of gravity along the bottom of a body of standing water. The maximum density is 2; with higher concentration the turbid current changes to a slide. Turbidity currents of high density might be set up on the sea floor by: (a) slumping, the material becoming more diluted ; (0) by a mud- flow on land reaching the coast and continuing along the bottom; (c) the waters of a heavily silt-laden river, if heavier than sea-water, might flow along the bottom beyond the mouth; (d) by churned up mud initiating a flow, which picked up more sediment and thus increased its density. A remarkable property of currents of high density is the fantastic power of transportation. With a destiny of 2 individual blocks can be transported 14,000 times as heavy as by a clear current of equal velocity and volume. , It appears likely that the currents might transport great volumes of silt, sand, and even coarser fractions over large distances of submarine slopes. They should continue over basin floors and mount the cpposite slope owing to their great momentum, then depositing the coarser fractions. The fine silt and mud would be carried back again to the deeper parts of the basin. Experiments showed that the deposits tend to be graded from coarse to fine both in a horizontal and vertical direction. It is believed that this mechanism may account for some cases of graded bedding in which coarse fractions are involved, and that are remarkable for the wide expanse over which each bed occurs, resting on undisturbed fine fractions of the preceding bed. Also the emplacement of deep-sea sands far from the original source might be accounted for in this manner. 216 ‘SUMMARY OF DISCUSSION Dr. Tulley inquired as to the origin in nature of the material postu- lated in the flows in Dr. Kuenen’s experiments. It was answered that the cause might be found in a slump, with the material taking up water to reach a stage where flow is possible. Dr. Shepard stated that this had been proved to occur in the case of mud at the head of a canyon. A process of filling up took place until a state of instability was reached and the semi-fluid material commenced to slide down. Dr. Kuenen further instanced mud-flows on land after floods, or the action of rivers containing sufficient silt to provide a specific gravity approximating to 2. Or, again, sediment might be churned up by waves to produce a mixture of high specific gravity. Mr. Banwell mentioned the examples of coastal drift on west coast of South Island of New Zealand, causing harbour silting. It had been estimated that about 5,000,000 cubic yards of material were so shifted annually along 150 miles of coast-line. Mr. Gage commented on the absence of erosion of previous sedimentations which was regarded by Dr. Kuenen as characteristic of this mode of deposition. He pointed out to the contrary that erosive effects are frequently encountered in sedimentary sequences of New Zealand Tertiary and pre-Tertiary. Had Dr. Kuenen always found an absence of erosion in graded bedding. And, referring to Mr. Banwell’s remarks, why was it found that at times sorting took place, and that at other times characteristically ungraded beds resulted from slumping ? Dr. Kuenen attributed this variation to differences in the type of mud, slope, particle size, and water admixture, through all gradations from a siding slump to a true turbidity current. Erosion may in part occur, but is often far from complete. Mr. Gage agreed that in cases where chips have been torn up by erosion the phenomenon was very noticeable, but that the converse case of lack of erosion tended to be less readily noticed. Dr. Lilhe referred to Bailey’s views on submarine landslipping. Were turbidity currents regarded as an explanation in these cases? It was pointed out that Bailey is not clear on this point. Dr. Lillie referred to variations in graded bedding in quarries, often with peculiar effects. There may be coarse to fine grading, interrupted however by lenses of thin bands often less than half a millimetre thick of carbonaceous material. Dr. Kuenen thought these might be attributable to remains of seaweeds and marine plants. Dr. Shepard spoke of cores in submarine canyons, as in Monterey Bay, showing well graded pebble sequences, with sharp breaks in the cores between the coarse stratum below and the fine above. He instanced many cases where fine material of turbibity currents has been carried considerable distances. Was it- possible that the fine material might be carried on when the coarser grades had been precipitated ? Dr. Kuenen inclined to the view that muddy water might get caught between the coarse particles and silt filtered off. Dr. van Baren objected that the total amount of mud in relation to water in Dr. Kuenen’s experimental buckets where S.G. 2 is attained, might far exceed anything occurring in Nature. Could we expect such a density of mud to flow in Nature without dispersion? Dr. Kuenen held that this depended on the shape of the bottom. Flows emerging from a canyon will disperse, but momentum will carry material a great distance. 217 Dr. Tulley questioned how the very restricted occurrences of slump- ing, as, for example, off the Columbia and Fraser Rivers, could give rise to widespread effects. It was pointed out that material may, however, travel long distances with steep gradients as at the bottom of canyons. Dr. Emery mentioned a distance of 70 miles in fresh water with a very low gradient. Dr. Tulley agreed that in the case of the Fraser Estuary mud might be abnormally quickly precipitated owing to the high salt content of sea- water. FORMATION OF THE SEA BOTTOM OF THE SUNDA SEA By Dr. F. A. VAN BAREN, University of Indonesia, Buitenzorg | Abstract} The Sunda Sea is the large shallow sea comprised of the South China Sea and the Java Sea situated between the Island of Borneo, the peninsula of Malacca, and the Isles of Sumatra and Java. The minera- logical research of bottom samples of the floor of this sea revealed that ten sediment- -petrological groups or provinces could be recognized, as listed below, in their standard mineralogical composition. STANDARD COMPOSITIONS Transparent Minerals in Mutual Percentages. | i | | & Pe ie ines 3 | OG | ies red cadies jes iia ee EN eS See eta). |S OS et To Oot ccs cet Oe tes re Sesh a/2S)} ea] sis be S/S/E/Ele/Slel2e|sis| S| 8/2/42) 2/8) s) 2) el3 By o | Bt |e |e Bla as! ia | S| |e et Sy er ea || 2 ae CIE INNIS /S/4]|malelal4|<4/G]/Slalalol) 3. RESULTS OF MEASUREMENT The present investigations have been carried out from 1940 to 1944. Localities were restricted to the coastal waters of north-eastern part of Japan, which are illustrated in Fig. 2. At most stations under-water illuminations were measured for three parts of spectrum, red, green, and violet light. The relations between the vertical extinction coefficients for these three bands of spectrum are illustrated in Fig. 3. In this figure the results obtained by other authors for the similar bands of spectrum at various localities are also reproduced simultaneously. It is noticeable from the figure that the relations between the vertical extinction coefficients for the different bands of spectrum are rather scattered, accompanied with the change of season as well as of localities. As an average relation between them we get following formule, which are also illustrated in the figure by straight lines— Ry = 4:8 gl -5, and ky = 0-89k,0-5, when ek, is smaller than 0-2, , = 1-25k,0-8, when kg is greater than 0-2, where ky, kg, and ky are the vertical extinction coefficients for violet green and red light respectively. The relations between the violet and green light are expressible by a single function. Between red and green light, however, it must be expressed by two different functions. Following conclusions are supposed from this fact: seston in sea-water equally increase the vertical extinction coefficients for green and violet light, but for red light they are less effective than for green and_ violet light so long as their total amounts are not enormous. In the very turbid sea-water, when the vertical extinction coefficient for green light exceeds 0-2—about ten times greater than for pure water—the effects of seston upon the vertical extinction coefficient for red light increase as well as for green and violet light, then a new relation between them appears. The results of measurements are classified according to the colour of sea in Forell’s scale. In the table, a result of measurement at the stations where more than five filters are used simultaneously are 299 a HOKKA/DO > LAKE AKAN a. vie AUMURI BAY 0 LAKE INAWASHIRO 2 (LAKE NUMAZAWANUMA HONSHU TOKYO BAY SURUGA BAY 20 2.0, OTAKENOUTI [ s oe USTER @ CLARKE xUTTERBACK ae We LOW /.0 DUT TERBACK & JORGENSEN A Mal ; % POOLE g ATHINS ° i 9 On vertical evlmetion coefficient for violet light verhical extinction coetiiccent for red light Ir Wa O2 @e/ wes 7, e O}/ Bil ‘ COV OY 02 05 10 OS! O! es 10 vertical exlinchon coefficient lor green hyht verlical extinction coefficient for green light Fic. 3.—Showing the relations between the vertical extinction coefficients for different colour of light 300 shown, while in order to calculate the average values of vertical ex- tinction coefficients for each class of colour of the sea, whole results of measurements are used irrespective of the numbers of filters employed. TABLE 1—THE VERTICAL EXTINCTION COEFFICIENT FOR EVERY CLASS OF COLOUR OF SEA IN FORELL’S SCALE Vertical Extinction Coefficient. Trans- Localities. paren- | Date. cies. | V—R1, | V—R2, | V—R3, | V—O1, | V—G1, | V—B1, | V—-V1, 665. 645. 615. 570 D2 e 495 405 5 Off Miyake Island 15-0 ie 0'0 0-442 | 0-119 | 0-095 | 0-110 | 0-140 | Oct., 1943 L. Numazawanuma 11-5 | 0-449 | 0-355 | 0-242 | 0-091 | 0-076 | 0-128 | 0-160 | Aug., 1943 Suruga Bay Fe 12-0 | 0-915 | 0-536 | 0-378 | 0-100 | 0-098 | 0-115 | 0-145 | Dec., 1943 Mean 0-682 | 0-446 | 0-310 | 0-096 | 0-087 | 0-122 | 0-154 9 Lake Toya a 15-0 | 0-870 0-349 | 0-144 | 0-083 te 0-250 | Aug., 1942 Amori Bay Ms 11-5 ae ai 0-346 | 0-131 | 0-123 | 0-118 | 0-188 | Oct., 1940 Lake Inawashiro .. 8:5,| 0-740 | 0-466 | 0-340 | 0-132 | 0-119 | 0-134 | 0-171 | Aug., 1943 Mean 0-809 | 0-466 | 0-388 | 0-136 | 0-108 | 0-126 | 0-203 | 14 Amori Bay se 9-0 | 0-850 0-450 | 0-138 | 0-119 | 0-378 | 0-525 | Oct., 1941 20 Lake Akan ye 11-5 | 0-581 0-359 | 0-179 | 0-165 Q-411 | Aug., 1942 Off Abashiri ae 8-0 | 0-829 0-148 | 0-141 | 0-081 1:6 Aug., 1942 Tokyo Bay* 4-0 | 1-324 0-511 | 0-327 | 0-336 0-926 | April, 1943 Mean : 1-002 0-448 | 0-254 | 0-270 0-994 27 Akkeshi Bay 6-5 | 0-766 0-376 | 0-505 | 0-111 0-301 | Aug., 1942 Tokyo Bay ae 4-0 | 0-944 .. |0-615 | 0-322 | 0-401 1-07 | April, 1943 Tokyo Bay a 3-6 | 0-982 | 0-474 | 0-304 | 0-141 | 0-223 | 0-265 | 0-819 | July, 1943 Tokyo Bay 3:0 | 0-857 oe 0-622 | 0-322 | 0-336 0-921 | April, 1943 Mean 1-012 0-525 | 0-310 | 0-326 | 0-459 | 0-903 35 Tokyo Bay 3:1 | 1-345 0-341 | 0-804 | 0-345 as 0-700 | April, 1943 Tokyo Bay 2-5 | 1-032 0-587 | 0-325 | 0-405 re 1-105 | April, 19438 Tokyo Bay 1-4 | 1-068 | 1-087 | 0-676 | 0-334 | 0-416 | 0-671 | 1-150 Feb., 1944 Mean 1-118 | 0-555 | 0-436 | 0-315 | 0-348 1:193 44 Tokyo Bay+ oe 2-5 | 1-204 0-645 | 0-369 | 0-399 0-955 | April, 1943 Mean 1-247 | 0-936 | 0-670 | 0-336 | 0-398 | 0-577 | 1-202 54 Tokyo Bay ae 1-7 | 1-240 | 0-733 | 0-510 | 0-272 | 0-359 | 0-483 | 1-202 | May, 1943 Mean os BG ol Be 0-683 0-401 a 1-190 65 Tokyo Bay ae 2-0 | 2-275 | 0-987 | 1-055 | 0-471 | 0-540 | 0-703 | 1-643 | June, 1943 *Mean of 4st. with equal transparency. 7Mean of 5st. with equal transparency. In the table the first column shows the colour of sea by Forell’s scale. The localities of observations are shown in the second column, the third column shows the transparency of sea-water, which has been measured by a white disk of about 30 cm. in diameter. The vertical extinction coefficients are shown in the table from the fourth to eleventh columns, the kinds of filters and the optical centers of response for each of them are written at the heads of columns. The last column shows the date of observations. Among the average values of vertical extinction coefficients in the table some irregularities which cannot be negligible remain still. In order to eliminate the irregularities the values of éxtinction coefficients are plotted on a sheet taking the wave-length of light as an ordinate and the value of vertical extinction coefficient as an abscissa. Considering the relations between the vertical extinction coefficients for red (V-R3), green (V-Gl), and violet (V-V1), the points representing them are connected smoothly for all classes of Forell’s scale. Thus we get 301 Nn O on Oo) oy Wo = 10 So ~O ZL cS wel S ZO 12) w s (4. i & 9 wW x 5 = 0} i & 7 001 | : 70O 600 500 AOO Wave - length in. ph Fic. 4.—Showing the average values of vertical extinction coefficients of sea-water Fig. 4, which gives the average vertical extinction coefficients of sea- water for all classes of Forell’s scale. In this figure the results of Professors C. L. Utterback and W. Jorgensen for deep sea-waters and the absorption coefficient for distilled water by W. R. Sawyer are also reproduced (line (2) and (1) respectively). Looking through the figure we noticed that the most transparent wave-length moves towards the side of long wave as the colour of sea becomes yellowish. The change of wave-length is, however, more remarkable for bluish transparent sea-water. The minimum vertical extinction coefficients and the wave-lengths for them are shown in table 2. TABLE 2—MINIMUM VERTICAL EXTINCTION COEFFICIENTS Minimum of Wave-length for Transparency. The Colour Vertical Minimum Vertical of Sea. Extinction Extinction Mean of Stations Average of Coefficient. Coefficient. of Observation. Near Japan. 5 0-088 530u 15-1m 16:1m 9 0-098 539 10:9 10:6 14 0-112 544 8-0 7-0 20 0-149 550 4-9 4-0 27 0-228 556 4-0 3:6 35 | 0:297 558 3°3 2°8 44 0:332 559 2-9 2-1 54 | 0-389 560 2-3 1:8 65 0-416 | 561 2-0 1:5 In the table mean values of transparencies at the stations of observa- tion as well as the average value for ‘each class of Forell’s scale in the waters near Japan, which are calculated by Dr. M. Uda, are reproduced. The former is rather large for yellowish colour of sea. This is probably due to the fact that in some stations the turbid riverine water covered over sea-water and it makes the colour of sea yellowish. The trans- parency, however, remains almost unchanged owing to the film of riverine water being very thin. This phenomena is fr equently observed in a bay into where a great river empties. The products of the transparencies and the vertical extinction coeffi- cients are almost constant for every class of colour of sea. The value of product is, however, about a half that obtained by Professors H. H. Poole and W. R. G. Atkins for the waters of English Channel. This is natural, because in the case of our experiments the minimum values of vertical extinction coefficients are used to calculate the product. LITERATURE (1) Poort, H. H., and Atkins, W. R. G.: Photo-electric Measurement of Sub- marine Illumination Through the Year. Journ. May. Biol. Assoc., XVI, p. 297, 1029. (2) Upa, M.: The Colour of Sea and Transparency in Waters Near Japan. Umi to Sova (in Japanese), X (8), p. 173, 1930. (3) SAWYER, W.: The Spectral Absorption of Light by Pure Water and Bay of Fundy Water. Contr. Canad. Biol. Fish., N.S. (8), 1941. (4) Poor, H. H. and Atkins, W. R.G.: The Use of a Selenium Rectifier Photo- cell for Submarine Photometry. Journ. Mar. Biol. Assoc., XIX, p. 727, 1932. (5) UTTERBACK, C. L. and JORGENSEN, W.: Absorption of Daylight in the North Pacific Ocean. Journ. du Conseil, 1X, p. 157, 1934. (6) Suzuki, H.: Photo-electric Cell and Photo-voltaic Cell. (In Japanese.) Tokyo, 1938, p. 342. RECENT ADVANCES IN CHEMICAL OCEANOGRAPHY IN JAPAN By M. IsHIBASHI,.Science Faculty, Kyoto University List OF TITLES IN THE SYMPOSIUM, WITH REFERENCES 1. On Lead Content in Sea-water and its Geochemical Meaning: The Age of the Ocean (1), by M. Ishibashi, M. Tanaka, and H. Hayakawa. 1943, Journ. Oceanogr. Soc. Japan, 2, 10. 2. On the Regularity of Quantities of Elements Dissolved in Sea-water : The Age of the Ocean (2), by M. Ishibashi and Y. Harada. 1943, Journ. “Oceanogr. Soc. Japan, 2, 84. 3. On Lithium Content in Sea Water and Bittern, by M. Ishibashi and K. Kurata. 1936, Journ. Chem. Soc. Japan, 60, 1109. 4. On Rubidium Content in Sea Water and Bittern, by M. Ishibashi and Y. Harada. 1942, Journ. Chem. Soc. Japan, 63, 211. 5. On Caesium Content in Sea Water and Bittern, by M. Ishibashi and Y. Harada. 1943, Journ. Chem. Soc. Japan, 64, 1049 and 1944, Journ. Oceanogr. Soc. Japan, 3, 185. 6. On Thorium Content in Sea Water, by M. Ishibashi and S. Higashi. 1948, Reported at 69th Annual Meeting of Chemical Society of Japan. 7. On Vanadium in Sea Animals, by K. Kimura and R. Fukai. 1948, Journ. Chem. Soc. Japan, 69, 75. 303 (93) . Micro-determination of Uranium by the Fluorescence Method, by M. Nakanishi. 1948, Journ Chem. Soc. Japan, 68, 42. 9. Copper, Lead, and Zmc Content in Sea Water, by K. Kuroda. 1940, Bull. Chem. Soc. Japan, 15, 441. 10. Chemical Composition of Deep Sea Muds in the Pacific Ocean: Red Clays and Radiolarian Oozes, by M. Ishibashi and Y. Harada. 1938, Journ. Chem. Soc. Japan, 58,569. 11. A New Improved Method of Separation of Gold from Sea Water, by M. Ishibashi and Y. Harada. 1939, Journ. Chem. Soc. Japan, 60, 1265. 12. On Chemical Compositions of Boiler Scales Produced From Sea Water, by M. Ishibashi, M. Shinagawa, and T. Shigematsu. 1941, Journ. Chem. Soc. Japan, 62, 44, and zbid.; 1942, 63, 781. 13. On Inorganic Constituents of Sea Weeds, by M. Ishibashi and R. Sahara. 1940, Journ. Chem. Soc. Japan, 61, 277. 14. On Separation and Quantitative Analysis of Halogens in Sea Weeds, by M. Ishibashi and R. Sahara. 1940, Journ. Chem. Soc. Japan, 61, 513: 15. On Copper Content in Sea Water and Bittern, by M. Ishibashi, K. Kurata, and T. Hirobe. 1940, Journ. Chem. Soc. Japan, 61, 726. 16. Chemical Compositions of Shallow Sea Muds Along Korean Beaches, and Values of Resources, by M. Ishibashi. 1941, Nipp. Gak. Kyokaish, 16, 379. ; _ 17. Chemical Studies of Deep Sea Muds in the Pacific Ocean} Rants 1122 by H. Hamaguchi. 1938, Journ. Chem. Soc. Japan, 59, 171. SUMMARY OF DISCUSSION Dr. Plesch, who presented the Japanese papers on behalf of SCAP, spoke to the meeting about the efficient organization developed for contact with Japanese scientific circles, and liaison with British and American workers. There was, he stated, a very complete tracer service in existence for individual workers and their publications. Semi- annual reports were issued on scientific projects, inquiries on detailed points being referred to the Japanese Ministry of Education. Direct communication with Japanese through the international mails was now possible. Japanese can send publications abroad, or written manu- scripts, but, strangely, there is still a restriction on typed manuscripts. The Japanese workers are showing an extreme willingness to exchange papers, in English or with English résumés. There is an extensive abstracting service by the Economics and Scientific Section of SCAP, principally through the normal abstracting journals, and _ scientific institutions in Japan are rapidly resuming outside relations. _ The relevant address was given as Economics and Scientific Section, Supreme Command Allied Powers, A.P.O. (U.S. Army) 500, c/o Postmaster, San Francisco. 304 SYMPOSIUM ON MARINE BIOGEOGRAPHICAL PROVINCES IN THE PACIFIC SURFACE BOUNDARIES IN THE SOUTHERN OCEAN By G. E. R. Deacon, Admiralty Research Laboratory, England [Abstract] More information about the Antarctic Convergence, the boundary between Antarctic and subantarctic waters at the surface, has been obtained by the detailed analysis of thermograph records obtained by the vessels of the ‘‘ Discovery ” Investigations (Mackintosh, 1946). The mean position is little different from that published in 1937, and the new figures strengthen the conclusion (Deacon, 1937) that the position of the surface boundary is closely related to the deep and bottom currents which are subject to little variation. Secondary fluctuations can be attributed to local causes, but it is found that half the reported positions fall within 25 miles of the mean position, and the extreme displacement may not exceed 100’miles. The average difference of temperature is 2° c., from 4° c. to 6° c. in summer, and 1° c. to 3° c. in winter, and ifit is less than 2° c. observations of surface temperature alone may not be sufficient to show exactly where the boundary is crossed. Many of the biologists who have examined the “‘ Discovery ” collections have remarked on the significance of the convergence as a boundary for species of plankton, fish, and non-abyssal bottom-living animals. Its position is also related to the distribution and stratification of the bottom sediments. R. C. Murphy has given a list of fifteen birds typical of the Antarctic zone, twenty-nine typical of the subantarctic zone, and eleven common to both. The subtropical convergence between subantarctic and subtropical water is usually marked by a difference of 4 or 5° c., from approximately 12° c. to 16° c. in summer and 8° c. to 12° c. in winter, and the increase in temperature is accompanied by a sharp increase in salinity. It has been found to limit the distribution of some species of plankton, fish, and bottom-living animals. The simplest explanation of the sharp difference in physical properties is that it marks the convergence of water movements with northward and southward components. The boundary is sharpest where a current convergence is most likely, as in the regions south of the Brazil current, Agulhas current, and East Australian current, and it appears to be less sharp in the eastern half of each ocean, where the current in middle latitudes has a more northerly trend. The position of the subtropical convergence appears to be subject to considerable variation, especially in the eastern half of each ocean, and Defant (1938) has suggested that it would be better to describe it as a convergence region rather than a line. This should prove a useful suggestion, though it is likely to prove that the convergence region is one over which a sharp boundary fluctuates, rather than one of gradual change. Stephenson (1947), dealing with littoral regions, thinks the term “ subtropical ” misleading when it is applied to water which may be as cold as 12°c. in winter, and prefers the names “warm temperate” and ‘“‘ cold temperate ’’ to subtropical and sub-Antarctic. 305 LITERATURE Deacon, G. E. R. (1937): The Hydrology of the Southern Ocean. Discovery Reports, 15, 1. Derant, A. (1938): Aufbau und Zirkulation des Atlantischen Ozeans. Preuss. Akad.d.Wiss. Phys.—Math. Klasse, X1V. MacxintosH, N. A. (1946): The Atlantic Convervgence and the Distribution of Surface Temperatures in Antarctic Waters. Discovery Reports, 23, 179. STEPHENSON, T. A. (1947): The Constitution of the Intertidal Fauna and Flora of South Africa. Part III. Annals Natal. Mus.; 11, 207. SUMMARY OF DISCUSSION Dr. Murphy referred to the critical work in New Zealand of Mr. Fleming, on the bird life on either side of the subtropical convergence which divides the two main islands of New Zealand. Mr. Fleming gave an account of his work in 1938 in attempting to apply the oceanographic and sea-birds correlation of Dr. Murphy to the New Zealand region. A strong correlation was obtained, together with some anomalies. With regard to the latter it was intended to reserve them for review in the light of further oceanographic data as this became available. New Zealand coasts were washed in the Cook Strait region by a belt of mixed waters, which was ornithologically intermediate, having two boundaries, the one at the south being more potent. The littoral marine faunal provinces were well correlated with the oceanographical results to a greater extent than Dr. Deacon had indicated. Powell’s faunal provinces were briefly discussed. Wolfgang Schott’s work on the stratification of bottom deposits was cited, and from speciation of one New Zealand bird genus (Pachyptila) in Pleistocene times, Fleming had postulated a migration of the convergence. The New Zealand situation was complicated by anomalies, probably partly due to inadequate information. A much closer grid of stations was required. Mr. Fleming agreed with Dr. Deacon as to the thrill of passing over the convergence with the accompanying sharp changes in birds and surface fauna. He recalled the appearance of Barracuda on crossing the sub-tropical convergence. : Mr. Powell referred to his investigation of the “ Discovery ” mollusca, and pointed out that the plotting use of the subantartic and cold temperate zones, aS shown on Dr. Deacon’s map, was not quite followed. Dr. Deacon stated that the “ Discovery’ boundaries fitted in well for subabyssal polyzoa, and pointed out that Stevenson’s work was applicable only with shore-dwelling animals. It did associate Mac- quarie Island with South Georgia, though Kerguelen and Herd Island were placed in the cold temperate. Professor Yonge concluded with the observation that with littoral fauna the air temperature is a factor of equal importance with sea temperature. PAST HISTORY OF THE DISTRIBUIION OF ANTARCTIC ALGZA: By C. SKOTTSBERG, Gothenberg, Sweden [A bstract| The author has tried to compile a list of the truly Antarctic seaweeds occurring along the coast of the continent and adjacent islands. Although South Georgia lies south of the Antarctic convergence it is excluded. This floristically remarkable island is transitional in character. 306 An overwhelming part of the seaweeds known have been found in the American sector of West Antarctica on the Pacific side. Little is known about the flora of East Antarctica, the most important contribution having been made by “ Banzare”’ expeditions. The author is at present studying this collection, which adds much to our knowledge and contains some undescribed species. At present we know 12 Chlorophycee, about 65 Rhodphycee, and 18 or 19 Pheophycee from the Antarctic. All groups contain some endemic species, but the bulk is formed by subantarctic forms, of which some are Circumpolar. A remarkable degree of endemism is shown only by the Pheophyceea, with 5 endemic genera, some of which have no close relatives. The arctic flora gives exactly the same impression, but is much richer. This is in accordance with the distribution of land and sea in the north, where the transition from the Subarctic to the Arctic zone is quite gradual. The Antarctic and subantarctic zones are separated by wide expanses of water, probably crossed by dispersal units only on rare occasions and hardly ever in the direction north-south, or vice versa, because of the west wind drift. Another reason for the poverty of the Antarctic lies in its history since the beginning of the Ice Age. Life conditions are very severe, as they are now, suitable localities for marine alge in the intertidal region being of very limited extent because of both the extension of the inland and shelf ice and of the destructive action of the sea ice in motion. During the maximum glaciation conditions must have been much worse, the refuges were few, and only the hardier species survived. During the post-Glacial a gradual reimmigration took place. Even South Georgia was almost entirely ice-covered and its marine flora must have suffered great losses. Nevertheless, it shows a remarkable number of outstanding endemic types. The glaciation did not have the same destructive influence in the Arctic, where the alge could retreat south along the coasts of both the Altantic and the Pacific. It is very difficult to get a firm hold on the pre-Glacial history of the Antarctic alge. They belong to an extreme cold-water flora which, as far as we are able to judge, cannot exist under Temperate conditions. Marine alge are sensitive in this respect ; they are, all over the globe, distributed in distinct zones of temperature. If we go back to the Tertiary, we soon get to a point where there was no cold water at all. Of course, already during Eocene—and before—climatic zones existed, and they became more pronounced in the Oligocene and Miocene, but the land flora in the Polar regions was more or less subtropical, both south and north, and the seas must have been warm. A source of cold came into existence with the formation of mountain ranges, in the south, the Antarctandes. Here Temperate-montane and Alpine land floras - developed. Snow and ice accumulated on the mountains, which were higher than now, glaciers descended into the valleys, and eventually reached sea-level, inaugurating the era when a marine flora, adapted to cold water, was born, the ancestors of the present-day flora, just as the Sub-tropical penguins, found as fossils in old Tertiary strata on the Palmer Peninsula, are the ancestors of the living cold-water penguins. Thus the truly Antarctic marine bios is comparatively recent. Another factor to be taken into account is the supposed land connections between the Antarctic and subantarctic. They affected the currents profoundly, and circumpolar dispersal was impossible. We face a very complicated problem here, and it will require a lot of thinking to understand the influence of such land connections on the evolution 307 and distribution of plants and animals. Most likely the West Antarctic bridge was sunk during the final upheaval of the Cordillera and the definite cooling of the Polar zone. The connections Enderby-Kerguelen and East Antarctica - Tasmania and New Zealand are more hypothetical, | but we cannot explain the biogeography of the subantarctic zone without them. SUMMARY OF DISCUSSION Dr. Yonge suggested that the differences pointed out between the Arctic and Antarctic flora in numbers of endemics, might be explained by the fact that Antarctica was itself a continent, while towards the Arctic the northernmost parts of the great continents continue upward. Dr. Falla wondered whether the tolerances and physical needs of Macrocystis were sufficiently narrow to make it a useful indicator genus, as proposed by Dr. Skottsberg. It did not occur, it was answered, in the true antarctic. Dr. Deacon stated he had found it in the South Orkney Islands, and Dr. Skottsberg replied that this was a possibility which would prove very interesting. It was present certainly in South Georgia, but was very small compared with its occurrence at Kerguelen and the Falkland Islands in such thick belts that there was no chance of getting ashore. Miss Moore pointed out that New Zealand lay across the subtropical convergence. Many alge, including Macrocystis, reach their limit on the North Island coasts, serving to mark diagrammatically the margin of the convergence zone. Desmarestia was another case in point. Some northern species, especially on the east coast, are observed to overlap to the south. The Tasmanian algal flora agrees much more closely with our New Zealand North Island than with the South Island flora. This serves again to confirm the inclusion of Tasmania and the North Island of New Zealand within the subtropical convergence. Professor Chapman raised some further problems which he considered were opened up by Skottsberg’s paper. On Wegener’s Theory of Contin- ental Drift he (Professor Chapman) and Dr. Skottsberg did not see eye to eye. Professor Chapman still adhered to the continental drift ideas, and had heard no evidence from Dr. Skottsberg’s paper to confute that view. Dr. Skottsberg, in discussing the origin of cold-water alge, had claimed that a point must have been reached in the Tertiary where there was no cold water at all. But to-day, even in subtropical South Africa and California, we do get cold water welling up. The alge may have evolved in the pre-glacial period and survived in these masses of cold water. Antarctic mud had been shown to underlie the diatomaceous ooze, and if Dr. Skottsberg was correct in thinking that the waters were warmer it would be likely that a further deposit of diatomaceous ooze would underlie the mud. Dy. Skottsberg, in replying, did not under- rate the importance of the upwelling of colder waters, but poimted out that each such up-flow must have an original source, which is to-day the Polar ice-cap. No such sources could have existed during the early Tertiary. He agreed, however, that it was hardly possible that the subantarctic cold-water species could have evolved after the Tertiary glaciation. Professor Chapman wondered if the oceanographers could render assistance with the question of past cold-water occurrences. Dr. Deacon thought that little attention had yet been given to the problem raised. 308 RHE POST-MIOCENE EVOLUTION, OF MARINE FAUNAS IN HAE eS OUD WESis PACIIC SAN DES) BPARING | ON} a Ele PROBLEM OF MARINE FAUNAL PROVINCES By C. A. Freminc, New Zealand Geological Survey PERSISTENCE of the concept of biogeographical regions implies a consider- able degree of agreement between the distribution areas of different groups of organisms. Faunal boundaries based on the distribution of ene group are often valid for another group, provided that such groups occupy a common environment and share the same sort of dispersal mechanism. For the marine fauna and flora of the continental slope these conditions hold, so that conclusions based, for instance, on study of mollusca are to a considerable degree valid for echinoderms or marine alge. By analogy, in studies of historical biogeography we may infer that faunal change in one group was paralleled in others, that the factors controlling invasions, changes in distribution, and extinctions, determined by study of fossils in one phylum, may apply to another phylum which has left little or no fossil record. Few groups of organisms have left as complete a record of their past distribution as have the marine shelled mollusca, and conclusions based on their study may shed light on the faunal evolution of other groups. This hope is offered as excuse for the title of a paper which deals entirely with mollusca. - Generic range charts have been compiled for the New Zealand Pliocene and Pleistocene mollusc fauna, based on collections from the Wanganui area, supplemented by published and unpublished information from other parts of New Zealand. The information was plotted against a time scale (Table 1) divided according to the system of stages used in New Zealand stratigraphy (Finlay and Marwick, 1947). Substages used in the Wanganui series and stages of the Hawera series have been proposed elsewhere (Fleming, in preparation). The boundary between Pliocene and Pleistocene is not certain, so that the local stage system is used in the diagrams that illustrate this paper. TABLE 1—SUBDIVISIONS OF THE NEW ZEALAND PLIOCENE AND PLEISTOCENE Series. Symbol. Stage. Substage. Approximate Correlation. Hawera. . H2 Oturian a ae flees Hl Puaroan ibe SE Gee: ce vee JS Putikian CO) ff Castlechiffian .. | Okehuan Wanganui NM 1 a Marahauan .. | NH f Nukumaruan TS ERG RE (Boundary uncertain.) Pliocene. a fi fMangapanian |\ Bf NVI aly ueoketan ‘ Waipipian O | Opoitian There are some 490 molluscan genera in the New Zealand Recent fauna for which some fossil record might be expected (shelled marine gastropods, pelecypods, scaphopods). Only about 350 of these have so far been identified as fossils, and lack of knowledge of the remaining 309 140 is some measure of the imperfection of the geological record. In order to formulate hypotheses concerning the history of the fauna in this study, the actual known occurrences. have been taken at their face value; the earliest vecord of a genus is inferred to be its first appearance in New Zealand and the absence of a genus after a period of occurrence is taken to indicate its extinction. The arbitrary acceptance of negative evidence implied by this empirical method is unavoidable if we are to generalize at all, but is a warning that such generalization is fallible and lable to revision with improvement of the data on which it is based. FAUNAL RICHNESS The total number of genera present in any one stage or substage varies, and may be used as an index of faunal richness (Fig. 1). In the Pliocene, 452 genera occur, and the total present at one time varies from 327 to 354. The early Pliocene faunas (Opoitian and Waipipian) are richer than later ones, and there are two periods of relatively low totals in the Mangapanian-Hautawan and in the Okehuan. Fluctuations in faunal richness are the result of extinctions on the one hand and invasions on the other. The form of the graph suggests that these opposing processes did not operate at random, but that the phases when extinction was the dominant process alternated with phases of invasion. H2. Hl. “CP CO NM NH WMWW O Fic. 1.—Total number of molluscan genera in New Zealand Pliocene and Pleistocene stages, plotted against time scale. For symbols see Table 1 NUMBERS OF IMMIGRANT GENERA AND OF EXTINCTIONS Figure 2 summarizes what is known of the appearance and dis- appearance of molluscan genera during post-Miocene time in New Zealand. The total “first appearances’ for a given stage or substage 310 30 20 ’ recovered temporarily at the beginning of the Putikian. FIRST & LAST APPEARANCES OF GENERA INTHE N. Z. PEIOCENE & PEEIS TOCENE First Appearances Last Appearances 9 --------- i fh S } “S / Ese | / / / | \ / \ ] \ ! \ | ] \ / / ! VIN / HAN ; / \ ! / \ 1 \ l / / / \ / \ se / ‘ ea if Nea tre Nereis eee eres is | oO R H2 Hi] GP Co NM NH WM WW .—First and last appearances of molluscan genera in New Zealand during IEniG, 2 Pliocene and Pleistocene time are plotted at the beginning of the interval representing that stage, and “last appearances”’ at the end of that interval. The marked inverse relationship between first appearances (= invasion) and last appearances (= extinction) is apparent. The times when large numbers of genera appeared were times when few extinctions occurred, and, conversely, when extinctions were numerous invasions were few. The invasion rate dropped steadily until the Mangapanian, had recovered by the Marahauan, dropped again to introduce the Okehuan, and The extinction rate rose highest in the two “lean periods.’ Thus the factors which caused the extinction of molluscan genera seem to have also inhibited the invasion of others. Conditions favouring a fairly continuous, though decreasing, invasion of genera were interrupted on at least two occasions by the temporary onset of conditions speeding extinction and sub- stantially slowing invasion. 311 AFFINITIES OF SUCCESSIVE FAUNAS The genera of New Zealand mollusca can be readily grouped in four ~ categories depending on whether they are: (1) endemic, (2) common to Australia and New Zealand, (3) distributed through the subantarctic zone of surface water, (4) common to New Zealand and to some part of the great Indopacific Region. More categories would be desirable, but have not proved feasible. In particular, it would be useful to subdivide the group showing Indopacific affinity. Some genera classed as Indopacific are present in Australia and seem to have come to New Zealand from there; others are unknown in Australia and seem to have reached New Zealand by a more direct route from the north. Marwick (1926) long ago stated that “Australian and Indopacific elements have undoubtedly reached New Zealand during the Tertiary.”’ When successive Pliocene and Pleistocene faunas are analysed (Fig.. 3) it is apparent that no catastrophic change in the percentage composition of the fauna occurred during the period. The Australian element increased by 5:5 per cent. and the subantarctic element by 1-5 per cent. at the expense of the Endemic and Indopacific. This relative stability of faunal composition is the result of a balance between the opposing factors of extinction and invasion, and suggests that throughout the period the New Zealand fauna shared the same faunal influences, with a slight improvement in contacts with the subantarctic and with Australia. ‘DERIVATION OF IMMIGRANT GENERA _ The “first appearances’’ of mollusc genera since the Miocene are analysed in Fig. 4. The graphs for the four groups of genera fluctuate in sympathy ; there is no simple alternation in the affinities and implied derivation of newcomers to the fauna; no period, for instance, when Indopacific “invasion’’ was replaced by . Australian “invasion.” (The number of subantarctic genera is too small to warrant generaliza- tion.) On the contrary, the several “ lean periods ’’ affected immigrants of all groups. There is, however, a marked (if fluctuating) decrease in the number of endemic genera that appear cryptogenetically, and the Indopacific influence, strong at first, is considerably reduced in the middle of the period studied, recovering temporarily in the Putikian substage. The high number of endemic genera that appear for the first time in the Pliocene deserves comment. For the vast majority of such endemic genera no immediate ancestors are known in New Zealand; our ignorance of some may be due to the imperfection of the record, but, for most, we must infer an origin in some other area, and later immigration to New Zealand seas. The places of origin of such genera may not have been far distant, in the many areas which have supplied no adequate record of their Pliocene fauna, such as eastern Australia, New Caledonia, and other islands to the north, and the Subantarctic. OCEANOGRAPHIC CHANGES That the periods of faunal deterioration noted in the above sections may have been periods of climatic deterioration is a plausible hypothesis and has been invoked by many students. to account for post-Miocene: extinction of genera. Many of the extinct genera are stenothermal in warm seas where they persist, and many of those which “ invaded” New Zealand between the “lean periods” are also warm-water ones. 312 [OO a AUSTRALIAN SU | — Hi is es ac 504 = RI | eo Fic. ee for i pee & Pliocene and NS nee fee ENDEMIC N Opoitian. S | ~ > OD OS SeG2USB0e8050R Se | BESRBESEBEBI Ee , | q 3 Xs 5 iis Ne Shi a . Sas a aro) NS OS8 |S N NIE am i Pe | | a Hitt : I] oo ae OU | ] f 7 be Z2u&eE \ hd are © = Poe eee Ole manne ze LY ap > O22 a a SEeSBeB! LOG! LP Sven s aN wl < Ze \ erent |e WeEOd ao eal Onoda = 6 Z \N = a = Z 2 ; semesat Tey 60) Ne ee a NO eo) ee ee led bela. 2 / : NX on Be Coo | 2 ; °| | 2G, / “leer Pipe [ue sers o Jie [ic \ ©) Leal oO y s @ = yo ie a8) fe) Ya) Re 2 va) . 4.—(A) Numbers of genera appearing for the first time in successive stages of the New Zealand Pliocene and Pleistocene: Endemic, Australian, Indo- pacific, and subantarctic genera plotted separately. (B) Histogram showing . affinities of genera appearing for first time in the New Zealand Pliocene and Pleistocene 314 165 ANALYSIS OF AFFINITIES ae GENERA APPEARING FOR FIRST® TIME | N2 NE NH = | IN THE NEW ZEALAND PLIOCENE & PLEISTOCENE The ‘first most acute phase of faunal deterioration coincides with the invasion of a small but significant assemblage of cool-water molluscs (Fleming, 1944) and probably with the earliest recorded glaciation in New Zealand (Gage, 1945). The second (Okehuan) deterioration has not previously been attributed to a cold phase. The two Hawera series faunas certainly fall into a period of time when glacial advances occurred in mountainous areas, but they are from “‘ raised beaches”? and thus more likely to be interglacial than glacial (Zeuner, 1946, p. 129). In periods of oceanic cooling in New Zealand, invasions of sub- antarctic mollusca could perhaps not counterbalance the extermination of subtropical ones, for the subantarctic fauna is relatively poor in genera and species, and contains a high proportion of rock and kelp inhabiting forms which are seldom preserved as fossils. Many subtropical genera, on the other hand, have vagile pelagic larve and live in stations which are preserved, so that the warmer phases of post-Miocene time have left a more distinctive record than the cooler. FAUNAL PROVINCES The present Indopacific fauna has sometimes been considered the living representative of the Miocene faunas of temperate seas, just as the mammal fauna of Africa has been dubbed a surviving Pliocene fauna. In the same way past marine faunas in New Zealand have close analogies with contemporary provincial faunas. The time has not yet come for biometric analyses of New Zealand fossil faunas such as have been made m California by Schenck and Keen (1937). Such analyses would establish a probable latitudinal or isothermal equivalent, in Recent times, for a past fauna. The analogies between living and extinct faunas are, however, close enough to suggest a sequence of events illustrated in Fig. 5. This diagram is based on faunal changes in the Cook Strait area, the modern “ Cookian Province.” The early Phocene faunas contained genera (such as Polimices, Olivella, Chetlea, Sinum, S&c.) suggesting conditions more tropical than those of the Aupourian of to-day. The cool water fauna of the Hautawan (Lower Nukumaruan) ~ can be compared with the Forsterian of southern New Zealand, and the succeeding warm faunas of the Marahauan (Upper Nukumaruan) show a return to subtropical conditions (Pterochelus, Ataxocerithium, Ella- trivia, Isognomon, &c.). After the second (Okehuan) period of inferred cooling the warm Putikian saw the arrival or return of genera now limited to the Aupourian or even warmer coasts (Zelippistes, Pterochelus, Anadara, Eunaticina, &c.). Later faunas are Cookian, but there are a few Aupourian forms in the second Hawera stage. Figure 6 shows in map form the extent of the movements of provincial boundaries implied by the analogies drawn. It would not be possible to interpret the fossil record in terms of past oceanographic conditions if there were no correlation between environ- ment and fauna, but there are plenty of anomalies. In particular it has been found in Europe as well as New Zealand that newcomers to a fauna, colonizing under the influence of a favourable environment, may survive the following opposite fluctuation, even if this survival entails tolerance of conditions previously intolerable. Such survivals are known in the fossil record, and help to explain the anomalous SUF |PLIOC ENE Pie Si WANGAN UI ae », SURO AREY gene - ™ @ reletee1 o> = Ser 2 os Sj ravi — aye 2) = S S = 2 W ro) S < o - = So =) 2. = a Sie : a ee > ee ig = = Z Sale eS fas) 8 3 }- fi oD 32/3 = { jen (@) 2 = g = =a 4 ,\ = @ @ ! vs ~» oOo, —_— yi | — © es a . 1 (qo) 3 = S i: Zz RU cE aires! age gee a BU Se) Bee oe oY ae (ex wm pr 0] == Oo = ‘ec me ou Bg > ©), ca ae Fic. 5.—Changes in the provincial affinities of successive Pliocene and Pleistocene mollusc faunas near Wanganui occurrence of, for instance, a group of subantarctic mollusc genera in the subtropical Aupourian Province (Fleming, 1944), and others of subtropical derivation in the subantarctic. The climatic fluctuations of late Tertiary and Pleistocene time | resulted in widespread changes in the distribution of organisms in temperate seas, changes which continued until the threshold of Recent time, and which may still be occurring. The boundaries between the Recent faunal provinces, however defined, must be considered transitory in terms of geologic time. Local faunas owe their constitution to the complex historic processes of immigration, local extinction, and local persistence, controlled in large part by past environmental change. In general, however, local faunal assemblages have persisted longer than the geographical faunal provinces they now inhabit. 316 NEW ZEALAND <= SHOWING == SOME POST-MIOCENE I CHANGES IN THE POSITIONS | | OF THE | MARINE FAUNAL PROVINCES 30 25 5 100 uf) MILES 100 sO fo) 100 200 KILOMETRES New a - Fic. 6 317 REFERENCES Finray, H. J., and Marwick, J. (1947): New Divisions of the New Zealand Upper Cretaceous and Tertiary. N.Z. Journ. Sci. Tech., Vol. 28, No. 4 (Sec. B), pp. 228-236. FLemInG, C. A. (1944): Molluscan Evidence of Pliocene Climatic Change in New Zealand. Tvans. Roy. Soc. N.Z., Vol. 74, pp. 207—220. GaGE, M. (1945): The Tertiary and Quarternary Geology of Ross, Westland. Trans. Roy. Soc. N.Z., Vol. 75, pp. 138-159. _ Marwick, J. (1926): The Origin of the Tertiary Mollusca of New Zealand. N.Z. Journ. Sci. and Tech., Vol. 8, No. 5, pp. 269-272. ; ScHENCK, H. G., and Krren, A. M. (1937): An Index Method for Comparing Molluscan Faunules. Pyvoc. Am. Phil. Soc., Vol. 77, No. 2, pp. 161-182. ZEUNER, F. E. (1946): Dating. the Past, An Introduction to Geochronology. Methuen and Co., Ltd., London. SUMMARY OF DISCUSSION Dr. Yonge pointed out that one of the gaps in the knowledge of the geological distribution is due to our lack of information as to breeding temperatures of the groups in question. Dr. Kuenen wondered if there was any reason for Mr. Fleming’s. modesty in disclaiming the development of New Zealand endemic species within the New Zealand region and postulating a yet undiscovered. origin elsewhere. Mr. Fleming replied that where a large population suddenly appeared thriving in an area where it had no known ancestors his philosophy of speciation—in which geographical isolation played a major part—would lead him to postulate an invasion from elsewhere. In-some cases the New Zealand endemic genera showed affinities with other Indopacific areas rather than New Zealand. AV NOTE ON TH GhOGRAPHICALY DISTRIBULION VOR Eis MARINE ANIMALS ALONG THE JAPANESE COAST By Ixuso Hamat, Biological Institute, Okazaki Higher Normal. School, Toyokawa, Japan Ir is well known that the boreal and tropical, or northern and southern, fauna are mixed in the Japanese coast. The number of animal species. and their distribution have been suggestively studied im relation to a quantitative indication of the geographical distribution by Otuka(1) (1936) about the marine Mollusca and by Kuronuma(2) (1942) about the flat fishes. Otuka has used the coefficient of closeness to compare the Molluscan fauna between several localities, which is the ratio of the number of common species between two localities to the geometric mean of their respective total number of species, and Kuronuma has given the latitudinal value for the flat-fish fauna of a given locality, which is. the mean of the latitudinal values of each _ species, + ( B — 0) — (4,200 — A)}, where B and A are respectively the latitudes expressed in minutes at the southern and northern limits of distribution of (1) Oruka, YANOSUKE (1936): The Faunal Character of the Japanese Pleistocene Marine Mollusca, as Evidence of the Climate Having Become Colder During the Pleistocene in Japan. Bull. Biogeogr. Soc. Japan, 6 (16), 165-170. (2) Kuronuma, Karsuzo (1942): “ Latitudinal Value,’ a Quantitative Indication of Fish Distribution, and [ts Application to the Flat Fishes of Japanese Islands. Bull Biogeogr. Soc. Japan., 12 (4), 85-91. O18 a species, 0 means the latitude of the Equator, and 4,200 means lat. 70° N. in minutes; therefore, the latitudinal value of a locality shows how much the faunal distribution inclines towards the north or south from the central locality at lat. 35° N. It has been observed that there exist some correlations of the coefficient of closeness or of the latitudinal value with the latitude. Here in this paper a formulation has been attempted in these correlations and an appropriate expression has been’ given to the mixed geographical distribution of the northern and southern fauna from the relation between the two indices. When the coefficient of closeness in the marine Mollusca calculated by Otuka (1936) are plotted against the latitudes, each locality being a centre, in regard to the localities of the Pacific coast, there exists the following relation, IO 2 OUGe elnas An me ooo dameode oa (1) where y is the coefficient of closeness, « the latitude, and @ and 6 constants. Putting %» to the latitude of the central locality, in which the coefficient of closeness necessarily becomes 1 and } = —a%o, accordingly from the above equation (1) log y = @ (% — Xo) where (x — %o) means a latitudinal difference between the central locality and a locality comparable with it, and a@ means the decreasing rate of log y with the latitudinal difference. Practically in the Pacific coast the values of a deviates from + 0-0602 to + 0-3098. Among the groups of localities having a respective centre, the uniformity of the mean values of @ given by a Wt (log y)/(~ — %o) /N, has been tested by the statistical method for small number of observations (1), with the result that no significant difference has been recognized. In the Japanese coast, as it may be considered that the shore-lines are nearly linear along a north-south projection, and that the environments change monotonously with the latitude from north to south, it can be supposed .that the values of a are nearly equal if any locality is the centre. Thus, in the above relation (2) a = + 0-134 is obtained, taking the mean of the total values, where the sign (++) is taken in the case southwards from the central locality and (—) northwards. . When % = 35° N.—that is, when Enosima or Misaki and their vicinities are taken as the central locality, the theoretical values of coefficient of closeness drawn at intervals of 0-1 on a map are shown in Fig. 1, from which it can be perceived that the Molluscan fauna in Enosima or Misaki and their vicinities decreases their common species with the distance from these localities to the north or to the south, and the ratio of faunal mixture with these localities can be read from the expression of coefficient of closeness in this map. The latitudinal value contains a similar conception to the coefficient of closeness, and the flat fishes and Mollusca are the groups bearing a similar ecological type.as a kind of bottom fauna, and therefore a parallel relation is expected between the two indices. Then, the distribution of points as shown in Fig. 2 are obtained when the latitudinal values of the flat fishes in every locality calculated by Kuronuma are plotted against (1) In this paper the statistical methods have Deen followed by MASUYAMA, MorosaBuro—1943: Syostrei no Matomekata to Zikkenkeikaku no Tatekata (Statistical Methods for Small Observations and Design of Experiments), Tokyo, and Tokeikagaku-kenkyukai (Society of Statistical ” Science Research); 1943: Tokeisttihyo i (Statistical Numerical Tables 1), Tokyo. 319 1Z6 130° 132) 134 136 138 140) Wace Fie. 1.—The distribution of the coefficient of closeness in the Pacific Coast the theoretical values of the coefficients of closeness of Mollusca calculated by the equation, log y = - 0-134 (x — 35), taking the localities north- wards from lat. 35° N. on (+) side and southwards on (—) side. The values of a in the coast of the Japan Sea are difficult to decide because: of less observations, but the coefficients of closeness have been calculated by using the same value of a as that in the Pacific Coast, supposing no difference in both coasts from the point of fact that the observed values in Toyama and Hukui are nearly the same as those at the same latitude in the Pacific Coast. As the points of Soya, Iturup Island, and Hukuoka 320 if (a)ay (0) Pacific 800 saat Japan Sea | 600 4900 200 Latitudinal Value Ny) 1) e) O -400 -809 South ~<———-35° N > North 1 - ( Coefficient of closeness) FalGeroe Fic. 2.—Correlation between the coefficient of closeness and the latitudinal value, and the rejection-ellipses distinguishing the type of distribution. Thick lines, rejection-ellipses ; thin lines, regression lines were far apart from the other points, they were excepted from both the Pacific and the Japan Sea groups, and as Hakodate and Aomori should be clearly influenced by both seas these points were together classed in each group. Thus.a straight regression would be expected in each group ; therefore the coefficients of regression were calculated as 9-98 in the Pacific Coast and 7:25 in the Japan Sea. Between these two figures no significant difference was recognized from these data under the level of significance of 0-01 available. 321 11—Pac. Congress Furthermore, supposing the group of these observational points as a — random sample taken out from the normal population of two variables, the rejection-ellipse(1) has been drawn at the level of significance of ‘0-01. By means of the rejection-ellipses differences of the type of corre- lation of the two indices have been tested between the Pacific and the Japan Sea coasts, and further it has been also tested whether Soya, Iturup Island, and Hukuoka belong to another type or not—that is, points fallen outside of the ellipse are distinguished from the type at the level of significance of 0-01. Thus it has been observed that the values of Soya and Iturup Island belong neither to the. type of the Pacific Coast nor to that of the Japan Sea, that Hukuoka is distinguished from the type of the Pacific Coast but not from the Japan Sea, and that between both types of the Pacific and the Japan Sea there exists no significant difference. Then the correlation between the distributions of the lati- tudinal values in the flat fishes and of the coefficients of closeness in mollusca probably shows no significant difference as well in the Pacific Coast as in that of the Japan Sea; in other words, the mode of distri- | bution of species in the flat fishes are parallel to that in Mollusca, but in the localities of Soya and Iturup Island the type of fauna is distinguished from that in which the distribution of species gradually changes with the latitude, mixing the northern and southern fauna in the Japanese coasts having the centre at lat. 35° N.—that is, at the latitudes of these localities the fauna contains scarcely southern forms; therefore, it may be estimated that the northern limit of distribution of this type is lat. -43-44° N. and oppositely the southern limit is lat. 26-27° N. It has been said biogeographically that the Japanese coast extends over the Boreal Pacific Province and the Tropical Indopacific Province, but their boundary is not so clear. This fact is natural from the view- point of coefficient of closeness, and rather the boundary must be made by the statistical conception. From this point of view the northern limit discussed above as that of the type of the main Japanese coasts may be just equivalent to the boundary between both Provinces. Nomura and Hatai(2) (1936) have divided Japanese seas into seven provinces from the point of distribution mainly in Mollusca and Brachio- poda. When northern and southern limits of distribution of species exist in a definite range it is possible to find out several species characterizing each province, but the distributions of many species deviate little by little from the definite range and extend over the imaginary biogeographical provinces, and therefore it is unnatural to set up a province only from the characteristic species in that range. Accordingly the biogeographical division is subject to an expediential boundary. The division can be expressed rather strictly in terms of the coefficient of closeness than by the border-lines. In order to discuss the biogeographical distribution it is rather necessary to take account of the gradual decrease in the number of common species from locality to locality or with the distance expressed in terms of the latitude, by means of the coefficient of closeness. (1) MAsuyama, M. (1943): Joc. cit. (2) Nomura, SitrHEr and Hatar, Kotora (1936): A Note on the Zoological Provinces in the Japanese Seas. Bull. Biogeogr. Soc. Japan, 6 (21), 207-214. 322 SUMMARY AND CONCLUSION « (1) The coefficient of closeness (v) of marine Mullusca is connected with the latitude (x) in the following equation, los y = a 4 => 5, where a and 6 are constants. When a given locality is taken as a centre, log vy = a (% — Xo), where %o 1s the latitude at the central locality, and a is defined as a decreasing constant of common species. Practically in the Pacific Coast a = + 0-134, being (+) for southern localities and (—) for northern localities from the centre. (2) The latitudinal value in the flat fishes is parallel to the coefficient of closeness in marine Mollusca, and these animal groups have a common ecological type ; from these facts a similar mode of geographical distri- bution are reasoned in these animal groups. (3) The type of distribution shows no significant difference between the Pacific and the Japan Sea coasts, and Soya and Iturup Island are distinguished from this type. From these facts it is estimated that the northern limit of this type of distribution is lat. 45-44° N. and the southern limit is lat. 26-27° N. in the Japanese coasts having the centre -at lat. 35° N. (4) The coefficient of closeness and the latitudinal value are respectively a characteristic index to show a faunistic change from locality to locality ; however, the former is rather superior to the latter in respects of possibility to compare the difference among localities and to estimate the type of geographical distribution, in the case of which the northern and southern limits are difficult to decide in the geographical ‘distribution of animals. And, further, the expression of decrease of the coefficient of closeness from the centre to distant localities is superior to that of geographical division into provinces expediently by reason -of the distribution of several characteristic species. 323 SYMPOSIUM ON PROBLEMS OF BIPOLARITY AND OF PAN-TEMPERATE FAUNAS ANTITROPICAL DISTRIBUTION OF FISHES AND OTHER 7 ORGANISMS(!) By Cart L. Huss, Scripps Institution of Oceanography, University of California WHEN naturalists travel from their home lands and waters in the North Temperate Zone to South Temperate regions, as many of us recently have, they are struck first by the bewildering abundance of strange life in the tropics and are then impressed, as they enter the refreshingly cooler regions still farther southward, by the reappearance of certain familiar types of plants and animals. True, these forms are mixed with strange organisms, but it 1s the familiar ones that engender the depth of feeling that comes with the reunion of old friends. Since it first attracted the attention of travellers from Europe to far southern lands this phenomenon has been called “ bipolar distribution ”’ or “ bipolarity,’”’ and has been variously explained. One of the theories, that of separate creation, might now be modified into one of independent adaptive evolution. Another idea has been that the similar forms of north and of south are relicts, which stemmed from a cosmopolitan biota of an early Tertiary period of relatively warm and uniform world climate. On this theory the disjunct populations were forced apart by the increasing heat of the Tropics and by competition with a recently evolved rich tropical biota. Still another concept is that the Tropics have been crossed and to some extent are still being crossed, along isothermal lines, the marine forms dipping into the cold deep sea and the land forms rising to cold mountain heights. Advocates of continental drift have found in their aberrant hypothesis an explanation of bipolarity, as well as of almost every other phenomenon of biogeography. A more recent and in general more plausible explanation, stressed by Berg (1933), is that the Tropical waters were transgressed during the- Pleistocene periods of global cooling. This is the theory to which I particularly subscribe, though I recognize that each alternative explanation mentioned (with the exception of local creation) could be supported by an impressive array of evidence and has probably been valid to some degree for some groups. In line with this theory of Pleistocene interchange of faunas across. the Equator we find, on examining a large body of evidence, that the phenomenon with which we are dealing is only in a very small degree one- of bipolarity. As Berg (1933) stressed, the vast majority of the related forms of life that occur on either side of the Tropic Zone, but not within it, inhabit moderate rather than high latitudes. Among marine fishes, as Norman (1938) showed, the Antarctic contains only a small percentage of groups or of species of Arctic relationship. A few forms may be cited as definite examples of truly bipolar distribution ; a much larger number may better be called biboreal or bitemperate, and those that are bitemper- ate are warm-temperate as well as cool-temperate. Furthermore, a (1) Contributions from the Scripps Institution of Oceanography. o24 considerable number of subtropical types are more or less completely | separated by the tropical biotas. The phenomenon with which we are dealing is not one of special resemblances between polar elements. but rather one of narrow to broad, incomplete to complete equatorial dis- continuities in the latitudinal distribution of plants and animals. It therefore seems desirable that we stop expressing ourselves and thinking in terms of “ bipolar distribution ’’ and that we adopt another term—I suggest “ antitropical’’—to apply to the forms of life that shun the Tropics (the term to apply also to this type of distribution). ‘‘ Bipolarity ”’ would then become “ antitropicality.”’ There are many patterns of antitropical distribution, because resemblances exist between polar, boreal, cool-temperate, warm- temperate, and even subtropical forms of life ; because the breaks occur along all the main coast-lines that cross the Tropics; and because the many bitemperate complexes embrace various combinations of two or more temperate biotas (perhaps less than half of the bitemperate series could rightly be classed in the ““ pantemperate ’’ category, to which I have occasionally referred). These various patterns could be illustrated by different groups of organisms, but I shall largely restrict my discussion to the marine fishes, with which I am most familiar. The bipolar pattern, as already indicated, involves relatively few fishes. In the Antarctic and subantarctic regions there occur, mixed with a much larger number of endemic types, a few species of families that are otherwise chiefly of Arctic or subarctic range—slime-eels (Myxine), skates (Raja), and hakes (Merluccius); also certain cods (Gadide), sculpins (Cottide), lump-fishes (Cyclopteridée), snail-fishes (Liparidide) , seapoachers (Agonide), and eelpouts (Zoarcide and Lycodapodide) (Norman, 1937, 1938). In the far south there are several species of Raja and a moderate number of zoarcids, but the other bipolar groups are each represented there by only one or a very few species. These Antarctic and subantarctic types seem to have been derived from the far north, where the same groups are much better developed. Most, perhaps all, were probably derived by isothermal dispersal, perhaps in part during Pleistocene periods when lesser depths would probably have been required in the transgression of the Tropics. The tropical crossings were probably chiefly effected along the western shores of the two great oceans. Indeed, as a result of the exploration of the United States Fish Commission vessel “ Albatross,’ Garman (1899) disclosed in the region of Panama living deep-sea representatives of half the fish groups here listed as bipolar—namely, Myxine, Raja, Merluccius, Liparidide, and Zoarcide. Some of the bipolar fish sets may retain an isothermal connection, as certain invertebrates almost surely do. The varying degree of differenti- ation displayed by the Antarctic representatives of far northern groups ‘ bespeaks widely different periods of isolation. The evidence of relation- ships and of paleichthyology, however, argues against the pre-Tertiary transtropical dispersal of the groups named above. Several subantarctic or south-boreal fishes commonly included in the “bipolar ’’ category appear, in contrast, to be ancient, probably pre-Tertiary relicts of groups that have failed to persist in the Tropics, either because of unfavourable physical conditions or because they were unable to compete with the rich faunas that have evolved there. In this category I would include, among fishes, the following fluviatile, 320 12—Pac. Congress anadromous, and catadromous types: (1) the southern lampreys, comprising the genera Mordacia and Geotria, each referable to a family distinct from the Holarctic Petromyzontide, and the distinctive and primitive teleost families Galaxiide, Aplochitonide, Retropinnide, and Prototroctide. Their trenchant separation from not clearly recognizable Holaretic representatives indicates prolonged isolation. A few other primitive teleosts, notably the subantarctic herrings usually retained in the genus Clupea, may be pre-Tertiary or early Pleistocene relicts, for they are of ancient lineage. Their degree of differentiation and their far-southern habitat suggest isolation since one of the earlier, intense periods of Pleistocene glaciation. _ Bitemperate fish types not only outnumber the bipolar, but also, as a rule, exhibit less differentiation and appear to have had their popu- lations disrupted by tropical waters for a briefer period. The species that exhibit no measured differences on the two sides of the Tropics and those that are only incipiently or weakly differentiated have probably been segregated into northern and southern populations only since late Pleistocene. Many of the bitemperate types—and among these we might better include some of those here listed among the bipolar—may have crossed the Tropics, perhaps chiefly in Dbistoesne times, by descending into deeper water. This is particularly probable for various more or less strictly bitemperate types of sharks, including the genera Hexanchus, Heptranchias, Notorhynchus, Heterodontus, Cephaloscyllium, some other scyliorhinids, Galeorhinus, Mitsukurina, Carcharias, Lamna, Tetroras [Cetorhinus|, Somniosus, and Echinorhinus, and certain species-groups of Mustelus and Squalus. Other bitemperate fish types that may have transgressed the Tropics by a deep-water isothermal route during the Pleistocene are the hagfish genera Eptatretus and Poltstotrema,; the john-dory (Zeus), an example of wide-spread Old World antitropical distribution ; also, in the Eastern Hemisphere, various gurnards (Trigli- dee), sinistral flatfishes (Bothide), and other groups ; in the eastern Pacific, such genera as Chetlotrema, Pimelometopon, ‘Coulollonsis, and Sicyogaster ; the scorpenid genus Sebastodes, a speciose North Pacific genus of which one species group has populated waters from Peru to Cape of Good Hope ; Oplegnathus ; and certain clinids. Many other antitropical fishes of the Temperate Zones, including most of the pantemperate types, have attributes that lead us to believe that they crossed the Tropics when the surface waters were considerably cooled, presumably during late Pleistocene time. Ecologically, they are surface-bound ; therefore incapable of transgressing equatorial water by the cool deep-water route. That they crossed the Tropics during the last cold period of the Pleistocene is suggested by their incipient * speciation. In this category of surface-bound recent transgressors of the Tropics we must include such shore-pelagic fishes as the sardine or pilchard genus Sardinops (of, California, Japan, Peru and Chile, Australia and New Zealand, and South Africa) ; the roundherrings of the genus Etrumeus (of the western North Atlantic, California, Hawaii, Japan, Australia, and South Africa) ; the anchovy genus Engraulis (of Europe, Japan, South Africa, and Australia and New Zealand) ; the similar anchovies of H26 California, Peru and Chile, and Argentina, which, as I shall presently show, constitute a distinct genus; the even more strikingly pantemperate jackmackerel (Tvachurus) and chub mackerel (Pnewmatophorus) groups ; the saury genus Scomberesox (of North Atlantic and South Temperate waters) ; the species of Seviola related to S. dorsalis ; Centrolophus ; several tunas (Thunnide) and tuna-like fishes; also Alepisaurus and various other rather pelagic types. As emphasized by Berg (1933), not only these fishes, but also various other organisms almost certainly had a surface-water connection between the northern and southern hemispheres at a geologically very recent time, very probably, in large part, during the last period of continental glaciation. Notable examples are sealions (Otariide), right whales (Eubalaena), and the giant kelp Macrocystis, which is said to be repre- sented in both hemispheres by the same two ecotypic varieties of a single species. Zoogeographical, paleontological, and oceanographical data keep accumulating to force the conclusion that the last period of glaciation was synchronous in the two hemispheres and that the isotherms of sea and land were then markedly displaced equatorward. The increased -winds from polar toward equatorial regions must have accentuated the convergence of the cool currents, along the eastern shores of the two great oceans. The tropical belt must have been narrowed and con- siderably cooled everywhere. Paleontological data from Europe and Africa, the occurrence of a land-locked salmon (Oncorhynchus) in Formosa, and the ichthyological data in the following paragraphs are samples of the evidence on which these statements rest. The paucity of the Panamanian marine fish fauna, particularly among the reef fishes, suggests widespread extermination by a marked cooling of the tropical eastern Pacific. This fauna is outstandingly rich only in certain families that characteristically inhabit mud and sand bottom, notably the drums (Sciaenide), marine catfishes (Ariidez), and anchovies (Engraulidide). A decimated reef fauna would nicely explain the obviously very recent establishment on the tropical American Pacific Coast, particularly on the outlying islands, of Indo-Pacific fishes. The broad intervening expanse of open water, stressed by Ekman (1935) as the most notable barrier in the circumtropical distribution of life, has no doubt allowed only rare strays to reach America from Oceania. Had they reached shores as saturated with life as are those of the Indo-Pacific area it.is hardly conceivable that these strays could have established populations. The former cooling of now essentially tropical waters, about the Cape region of Baja California, is indicated by the entrapment, in the upper part of the Gulf of California, of a rather large faunal element related to that of north-western Baja California and southern California. Most of the constituent types are no longer able to round the tip of the peninsula. The varying differentiation of the Gulf representatives, generally very slight and still unmeasured for some species, suggests the origin of these upper-Gulf types during several periods of Pleistocene global cooling, but chiefly during the last ice period. Somewhat similarly, the occurence in the Galapagos Islands of many Temperate Peruvian types, in part more or less differentiated, suggests transfer and establishment during Pleistocene periods of general oceanic cooling. 327 The occurrence of European types in South Africa, undifferentiated or weakly differentiated, and of Japanese types not only in South Africa but also in Australia, in similar stages of speciation, suggests that the Pleistocene cooling of the oceans was world wide. Even the vast Indo- Pacific area appears to have been cooled sufficiently to permit the passage of a limited representation of the warm-temperate fauna, though insuffi- — cient to exterminate any considerable part of “‘ the great mother fish fauna of the world.” Combining certain zoogeographical and oceanographic data, and accepting the strong evidence that the temperature relations of organisms are very conservative, we may infer the approximate amount to which certain tropical waters were cooled during the late Pleistocene, to allow the transgression of the Tropics by such fishes and other organisms. The evidence is particularly strong and uncomplicated for the long and nearly straight shore of the eastern Pacific, where, it is commonly assumed, the cool-water faunal connections were especially numerous. Along this coast many of the now disrupted forms, such as the sardine and the giant kelp, are separated by a tropic belt that extends from near Cape San Lucas (the tip of Baja California) to the northern limit of the Humboldt or Peru current, in Peru. The almost certainly late Pleistocene faunal connection between these present limits would, we may assume, have required the cooling of the ocean surface to approximately the temperature now prevailing in the region from Cape San Lazaro to Cape San Lucas—that is, off Magdalena Bay, Baja California. The surface temperature data averaged monthly for coastwise squares of 5° latitude and longitude indicate for this region a fluctuation ‘from about 18° c. in the spring to about 25° in the summer, and for the warmest area intervening between this region and the sharp gradient in Peru, a change from 26:5° in the winter to 28° in May. The difference between the monthly averages is about 8-5° for the coldest month and 3° for the warmest. Since, toward the warm end of their ranges, most cool-water forms breed in the coolest season, it is probable that during winter in the last Ice Age the surface of the shore waters of the eastern Pacific was cooled in the order of 8°, though not necessarily more than about 3° during the warmest month. That there was some cooling during the summer is suggested not only by the general data, but also by such facts as this: that the tuna clippers are unable to keep sardines alive at temperatures much above 26°. The decrease of about 8° in winter would account for the presumed annihilation during the late Pleistocene of much of the fish life of the Panamanian region, but not of all the fauna, for there is a large tropical representation about Magdalena Bay, where winter temperatures run low. ° Similar, though less definite, data for the western Pacific indicate that the equatorial waters there were cooled during the Pleistocene, but probably not more than 2° to 4° during any month. There is little evidence of extensive cooling of the western Atlantic Tropics during the Pleistocene, but in all probability the convergence of the isotherms and the equatorial cooling was very pronounced along the eastern shores of the Atlantic. (Se) iw) (2) LITERATURE CITED Brrc, Leo S. (1933): Die bipolare Verbreitung der Organismen und die Eiszeit. Zoogeographica, 1, 444-484. EKMAN, SVEN (1935): Tiergeogvaphie des Meeves. Akademische Verlagsgesell- schaft, Leipzig. 542 pp., illustr. GARMAN, SAMUEL (1899): Reports on an Exploration Off the West Coast of Mexico, Central and South America, and Off the Galapagos Islands, in Charge of Alexander Agassiz, by the U.S. Fish Commission Steamer ‘‘Albatross,”’ During 1891, Lieut. Commander Z. L. Tanner, U.S.N., commanding—XXVI : The Fishes. Mem. Mus. Comp. Zool. Havard Coll., 24, 1-431, 99 pls. Norman, J. R. (1937): Coast Fishes—Part Il: The Patagonian Region (In- cluding the Straits of Magellan and the Falkland Islands). Discovery Repts., 16, 1-150, figs. 1-76, pls. 1-5. (1938) : Coast Fishes—Part Ill: The Antarctic Zone. .7bid.,'18, 1=105, fplle U. SUMMARY OF DISCUSSION Professot Yonge cited as an example of the ease with which temperate forms traverse tropical regions, the recent appearance of the New Zealand barnacle Elminius modestus in docks in Britain. Further, he inquired whether a full analysis had yet been published of the situation in the upper part of the Gulf of California where an isolated population is locked in, corresponding to that of the same latitude outside, but differing from that at the opening of the gulf. An analysis was still bemg made and would shortly appear in published form, it was stated. Dr. Johnson mentioned the extraordinary case of barnacles ‘being transported overland to the Salt Lake of Utah. Mr. Powell stated that Dr. Hubbs had very conclusively answered the question to be raised by him in his paper following, as to whether some bipolar animals may or may not go deep in the tropics and as to routes of convergence followed between north and south. CERTAIN BIPOLAR ELEMENTS IN MARINE MOLLUSCS - By A. W. B. Powe Lt, Auckland Institute and Museum | Abstract] These notes are extracted from a report in preparation on the Antarctic and subantarctic Mollusca collected by the “‘ Discovery ” Committee expeditions during the years 1926 to 1937. * The material studied is largely from the American Quadrant. It seems evident that— (a) The greater part of the southern high latitude molluscs have been derived per the American Quadrant ; and (b) That the route was, and still remains, the continuity of the west coast of the Americas plus the “ Scotia Arc’”’ bridge to Graham Land and for certain deep-water genera the Atlantic - Indian Ocean Cross Ridge which extends eastwards between the Argentine Basin and the Atlantic Antarctic Basin, almost to the Kerguelen-Gaussberg (radial) ridge. Three gasteropod genera—Aforia, Fusitriton, and Acanthina—are instanced. * A. W.B. Powell, 1951, Discovery Reports, Vol. 26, pp. 47-196 329 The turrid Aforia is a- splendid example of a bipolar genus that “goes deep ’’ over the warm zones, 1.¢. A. okhotskensts, 50°—60° N.: .73 fathoms ; bottom temperature, SOB) in, A. persimilis, 1° N.: 741 fathoms ; bottom temperature, 38-4° F. A. magnifica, 64°S.: 152 fathoms; bottom temperature, 32°38° F. Certain littoral genera, Liriola (Northern) and Kerguelenella (Southern) are closely related, but no longer have a connected range. They have not “‘ gone deep,”’ which raises the question, were the cold water faunas of both hemispheres sufficiently close during periods of Pleistocene glaciation to allow of interchange of species ? SUMMARY OF DISCUSSION Dr. Hubbs commented on the peculiar pattern of avoidance of the Antarctic Continent claimed by Mr. Powell in the three genera discussed, and asked whether that might not represent polar extinction, rather than invoke the use of a series of land-bridges. In answer it was pointed out that there is no evidence on the Antarctic Continent of forms related to the three under discussion (two of which are deep water), and that the alleged land-bridge mentioned is actually a ridge at a depth of 2,000 metres. This ridge, or series of ridges, may have been much shallower during an earlier period. 330 SYMPOSIUM ON PROBLEMS OF EUSTATISM IN THE PACIFIC BASIN AND RIM SUBMARINE CANYONS IN THE PACIFIC AND THEIR BEARING ON EUSTATISM By Francis P. SHEPARD, Scripps Institution of Oceanography, University of California | A bstract}| The submarine slopes along the margins of the Pacific are creased with numerous submarine canyons. Recently the canyons have also been discovered outside the deeply eroded portions of the Hawaiian Islands. Depths of half a mile or more are found in the outer portions of these canyons. Investigations of typical submarine canyons in the California area have been made by bottom sampling, submarine photography, and by diving operations. The results of these studies have shown that the canyons have charfacteristics which are exact duplications of typical land canyons. Many of the submarine canyons are known to be direct continuations of river valleys on land. Since all oceanographic data obtained to date serve to show the virtual impossibility that the canyons could have been formed by any other process than river erosion it becomes evident that widespread submergence must have taken place. If this has been the case it should also be indicated by other lines of evidence. Recent soundings show that there are flat-topped seamounts in many parts of the Pacific. These have depths varying from a few hundred to more than a thousand fathoms. The flatness is indicative of wave-bevelling when the submerged mountains stood much higher in relation to sea-level. The discovery of rounded cobbles on various elevations of the sea-floor gives more evidence of submergence. Finally, the borings into four coral atolls -have all shown that shallow-water deposits extend for at least a thousand feet below sea-level in all cases; in fact, the submergence of atolls in general seems probable. The explanation of the widespread submergence is not clear, but the possibility should be considered that it has been due to a change of sea-level rather than of the lands. An alternative which seems somewhat more likely is that diastrophic submergence has been proceeding over a long period of time, but that sea-level changes have also been significant in producing the present conditions. SUMMARY OF DISCUSSION Dr. Atwood asked if there really had been any careful research into the quantity of water required to produce the ice of the Pleistocene glaciation. Dr. Shepard did not think so, but felt that some geologists rather underestimated the thickness of the ice. In view of the evidence of Tertiary submergence, he was of the opinion that it played the chief part in the formation of the canyons rather than lowering of sea level due to glaciation. ID. “vevoad stated that in his judgment these Ae ier canyons represent a short period of time and were formed by extremely quick action of running water at some period of emergence, and felt that the amount of water held as ice should be considered, Jol. Dr. Tully remarked that the steep walls and flat floors of the land canyons can be followed out to sea, and then asked if Dr. Shepard had investigated the canyon off the boundary of Canada and U.S.A., which was 2,000 fathoms at the inner limits and 2,000 to 3,000 fathoms at the outer limits. Dr. Shepard considered the upper part of this canyon to be a glacial trough, but out beyond that it was a typical submarine canyon. Dr. Tully asked how the steepness of the canyon walls could be main- tained, and Dr. Shepard replied that all the troughs have extremely steep walls, and may be a result of the constant disintegration resulting from marine borings. The glacial valleys have steep walls, but all types of barred basins that the canyons have not. You would maintain then that these canyons are fundamentally of the river origin, said Dr. Tully, and in reply Dr. Shepard agreed, stating that they are at right angles to the coast, whereas fault-structures are parallel to the coast. Dr. Shepard then exhibited the depth-sounding records of the steamer express from Wellington to Lyttelton. Dr. Cotton said that the submarine canyons were quite obvious features of submergence, but could not local movements of land produce the submergence ? On the New Zealand Marlborough coast enormous block-faults are a prominent feature, and there may be block faulting under the sea off the coast. He felt he could not trust subjective contouring of the large canyons as much as that of the smaller canyons. Dr. Shepard agreed that the subjective drawing of the contours by Veatch and Smith must be treated with reserve. Mr. Fyfe remarked that several years ago the Union Steamship Co. -carried out extensive traverses taking depth soundings from Cape Campbell to Akaroa. The contours indicated that the canyons in this area mentioned by Dr. Shepard were basin-shaped and parallel to the coast, and he agreed with Dr. Cotton that they were probably structural. Dr. Cotton added that if such canyons are found off the Dunedin coast he would not question them because the geology at Dunedin is different from that at Kaikoura. ; Mr. Healy asked if these might not have been warping apparently round the margin of the Pacific which is an active belt, but, on the other hand, Dr. Shepard had illustrated similar canyons in the stable areas of the Atlantic. Did the longitudinal profile show warping or not ? Dr. Shepard replied that under-water canyons are just as large on the Atlantic coast as they are on the Pacific} and that the longitudinal profiles did not show any warping. He was inclined to agree with Dr. Atwood in stating that they were cut very rapidly. In reply to Dr. Westerveld’s query—Do these canyons go to different depths or are they fairly constant ?—Dr. Shepard said, “ That is our weakest point and will be the subject of further investigation with the improved apparatus that is now being installed.’’ He could not say definitely that they all ended at a certain more or less constant depth. NOTE ON DROWNED ISLANDS IN THE PACIFIC By RicHARD A. SONDER, Zurich, Switzerland Ir seems of interest in the framework of this symposium to call attention to a curious level problem connected with the flat-topped seamounts existing in great number in the Pacific. As I have presented a more extensive paper to the eighteenth International Geological Congress in London, only a short exposition will be given hereafter, 332 Plotting the number of known seamounts by classifying them according to the depth in fathoms of the top (from 500 to 1,000 fathoms) ‘in a graphic representation (see figure) it becomes obvious that certain , levels are clearly preferred. The result is practically the same if we use only the data given by Hess (1946) or the general sounding list of the Hydrographic Office at Washington (the two lower curves) for the Pacific | north of the Equator (Pilot Chart 2603). The visible maxima seem to be more or less evenly spaced (about 80 fathoms) especially towards depth. If the seamounts are drowned islands and are the older the deeper below the actual surface they are, we can hardly escape the conclusion that all islands in the open oceans are subjected to a slow secular drowning. One probable cause of this slow drowning may be the secular sedimenta- tion in the open ocean, as Hess has suggested. If for rather obvious reasons the sedimentation rate on the flat-topped submarine cones is less than on the surrounding ocean bottom, then a slow sedimentary burying of these cones must take place with the ages, calling for a slow drowning of the tops due to isostatic adjustment. Recent probing of bottom sediments, made on a flat-topped seamount in the Atlantic, north- east of the Bermudas seems to confirm this explanation. The top plateau stands at 841 fathoms and the sounding core of the sediments showed Eocone chalk below 8 in. of globigerina ooze (Ewing, 1948). On the surrounding deeper ocean bottom the sedimentation is far more intense, and only far younger sediments can be found there in the cores. There may be other causes for the secular drowning such as a tectonic deepening of the oceans with time, an increase of the total water content. I have dealt with these possibilities in other papers (1942, 1948). Assuming that these flat-topped seamounts are old volcanoes which preferentially rose at times of pitched tectonic diastrophism within the ~ earth's crust, one is tempted to parallelize the preferred levels of the eraph with the times of pitched tectonic volcanic activity, clearly visible in statistics of radioactive age determinations of minerals (Holmes, Wahl). Such an attempt has been made in the graph. If this interpretation should be correct, then the secular drowning rate of the seamounts would be about 110m. in a hundred million years. How does such an estimate match with known borings on coral islands, which may be seamounts with an age younger than the first appearance of corals in the seas? To the International Geological Congress some new data have been presented in this respect. According — to Wells and others (1948), borings down to about 760m. (2,556 ft.) on Bikini were still in the Lower Tertiary. Also on the other atolls, where borings are known—for instance, Funafuti—the results were similar. Notwithstanding that these results suggest at first sight a far higher sinking rate of these islands than the present estimate, it is not certain that this must be so. The borings made up to date are marginal borings and do not give the conditions at the centre of the atoll, where we have to expect probably the original volcanic cone. Coral islands do not only grow upwards, but also sidewards. Coral material broken loose by wave action may roll down the submarine slopes, with the result that in marginal borings beds of certain age are found at far lower levels than in more central borings. As we have to consider also the possibility of special tectonic level displacements which may have affected certain islands or of especially strong displacements of sea-level during the more recent history of the 333 13—Pac. Congress 009% 005% 00" OOLE 00l£ 000£ 0082 002 $J9jaw ayers ‘ 002 swoyyey aje2s uea 0 uado ul Sujdap papunos umouy 0092 SWOUJ2s Ul AIUaIAJJIP |3Aa| apfir0abjosaquinu =e (11Nyiqnop) sseah uoljjiwW abe payejodsayul S4ajaW 9/2IS O06! 008) QOL 009) 00S 0041 00st 0052 0042 00%2 0022 0012 Swoujej 3j22S 0001 008 uea2o uado ul Syidap papunos umMouy a) SS SS Se i 1) N fo} .e) ———— — — — OH — - sjohnB umouy wo1) SBuipunos ' ‘ S2h 2h 081 dul 2 ueluasney 2 ueiyjob J ueluoiny 2 ueibueyey OL 6 8 Z 9 Ss 7 pat TA TA IK fiyinyaeoipes fiq | (14eM) S4eah uot Ui abe (0095) (054) (02s) 22ut Syeafi uoijiw ui yjbus; 9)2fi2036 b > wisfixosed 31u042a) Jo sequnu IX 176 108 5 O¢d ueimopajed ¢ ymecsaiyalte At Sy TaN TUES | | | if | | | Ost 2 uedsien pair C 1S) 002 ajaAd auidje ‘ 6S 304 earth, it is obvious that the whole problem needs still far more data in order to find a reliable explanation of the origin of the seamounts and their age. In the meantime the interpretation of the chart could at least suggest that these drowned islands show some features which go back to the oldest history of our globe which we might still be able to decipher in form of geologic time-marks. REFERENCES Hess, H. H.: Drowned Ancient Islands of the Pacific Basin. Amey. Journ. Sci., 244, 1946, pp. 772-791. SONDER, R. A.: Shear Patterns of the Earth’s Crust, &c. Tvansact. dmer. Geoph. ' Union, 28, 1947, p. 939. Drowned Islands and the Origin of the Oceans. © 18th Int. Geol. Congress, London, 1948. We tts, J. W., and others: Drilling on Bikini Atoll. 18th Int. Geol. Congvess, London, 1948. SOME PACIFIC AND ANTARCTIC SEA-FLOOR FEATURES DISCOVERED DUKING EES: UlSa NAV Ne AN PARC ELE EXPEDITION, 1946-1947 By Robert S. Dietz, U.S. Navy Electronics Laboratory, San Diego 52, California | Abstract | nee the U.S. Navy Antarctic Expedition, 1946— 1947 (Operation HIGHJUMP), the recording echo sounder of the U.S.S. ‘‘ Henderson ”’ indicated the presence of a number of previously undiscovered sea-floor features. Several large, isolated, non-flat-topped seamounts were found, the shoalest of which rises to a depth of 540 fathoms. A volcanic origin is presumed for most of these seamounts as they are symmetrical in form and have slightly concave flanks varying in slope from 10 to 21°. A spectacular, asymmetrical, fault-block escarpment with a foredeep was discovered north of the Easter Island Swell. This two-mile-high ridge has a slope of 11° on one side and a calculated slope of at least 63° on the other. Thus, this feature is more precipitous than any sub- aerial fault-scarp of comparable magnitude on the face of the earth. Another large escarpment was discovered extending out from Antarctica. Profiles of the continental slope of Antarctica south of the Indian Ocean show it to be smooth and gentle, suggesting extensive deposition. No submarine canyons were definitely identified. The break-in slope between the shelf and slope occurs at depths from 230 to 280 fathoms. This is much deeper than the usual break-in slope which occurs at about 75 fathoms in most other parts of the world. It may be due to deep erosion by icebergs and glaciers, but certain other considerations suggest that it may result from the isostatic depression of Antarctica because of ice loading. Most of the Pacific traversed appeared to have irregular topography, but the basins around Antarctica are smooth and comparatively featureless. I. INTRODUCTION - During operation HIGHJUMP the U.S.S. “ Henderson ”’ (DD-785), under the command of Commander C. F. Bailey, made continuous soundings along her track with a model NMC-2 (RCA) echo sounder using 17 kilocycle sound pulses. Soundings of less than 2,000 fathoms 339 were recorded automatically on a tape, and soundings of greater depths were obtained by the eye-ear method every hour. Because almost all of the ocean bottom traversed is deeper than 2,000 fathoms, a continuous automatically recorded profile was obtained of only a few topograpically positive features such as the tops of seamounts cr escarpments. In this report a few features displayed on the “‘ Henderson ” fathogram are reproduced and discussed because they are of special geological interest. II. SEAMOUNTS A number of new seamounts were discovered during the San Diego to Antarctic passage. Four were found in the abyssai ocean off Baja California ; an especially large seamount was discovered in the south- west Pacific off New Zealand. Figure 14 shows two symmetrical seamounts that were located about 300 miles south-west of Allaire Bank, off Baja California. The larger seamount rises to a sharp peak at about 860 fathoms and the smaller rises to a peak at 1,400 fathoms. The sides of these seamounts are fairly steep, having a maximum average slope angle of 19°('). Extension of the bottom echo when crossing the peaks indicates steep slopes parallel to the ship’s track and suggests that the vessel “ side- swiped ’’ the seamounts rather than passing directly over their highest peaks. Another seamount (Fig. 1B) was discovered off Baja, California, about 130 miles north-west of Allaire Bank, rising 1,400 fathoms from the abyssal sea-floor to a peak at 900 fathoms. The north side is irregular and concave and has a slope of 12°; the south side is straight and featureless and has a slope of 16°. The summit is pinnacled and shows no evidence of terracing or truncation. The seamount shown in Fig. lc rises to a sharp peak at 540 fathoms. This symmetrical feature was discovered 220 miles west of Alijos Rocks, off Baja, California. Its slightly irregular and upwardly concave sides have an average slope angle of about 12°. The terrace which is present on the north slope at about 800 fathoms may be the result of wave erosion, but such a wave-cut origin is very questionable because echo extension suggests that this terrace is of rather limited horizontal extent normal to the recorded profile. Another seamount (Fig. 1D) was crossed near Hiva Oa, in the Marquesas Islands, the presence of which is suggested by soundings on published charts. The flanks of this feature have a slightly concave form. The steeper northern side has an average declivity of 13°, with a maximum slope of 21° near the summit. The somewhat gentler south flank is marked by a series of pinnacles. A deep and irregular plateau extends to the north-east of the seamount. Some of the atolls of the Marquesas Group presumably rise from this plateau. (1) In this report the apparent slope angles are corrected assuming a 30° effective half-angle of the sound-beam. In other words, the sound-beam is assumed to be semi-directional. However, the effective half-angle of the beam cannot be accurately determined since it varies with numerous. factors such as gain setting, roll of the ship, depth, &c. This correction is significant only for slopes greater than 15°, and the true slope is always greater than the apparent slope. The apparent slope is obtained by correcting the fathometer tape-slope for vertical exaggeration. ; SATIN Ot 6) e°s X WOTLHAA M LE“6ET S €9-60 “SI sysantuy vig INOONVES i ATSDR 1 Peak am Drs veasie 2°9 % TWOLLMGA MLe-6ll N gi-$e *dALIVO Wea do INDOWVES Baya y Lagasse! we i 4 i ~SH ITH saan meme | OL (0) tL X WOLLMIA M 00-@2T N LO-Tz “dITv¥O VPA Ado { INNONVaS bo eee ree ae te Pee oe : Msi a0 SATIN GL X TOTLYAA N 9T-"2T N 8T-LT *arTyo eva dao INNONVES ' | WOLlLOg. | i f $ AVNSIS ONIODLNO UE: ) ar) eo Fic. 1.—Echo sounder bottom trace (fathogram) of four Pacific seamounts The largest seamount encountered on the cruise (Fig. 24) is located in the south-west Pacific about 1,000 miles west of New Zealand in a sparsely-sounded region. This feature rises from a sea-floor depth of 2,700 fathoms to a minimum depth of 600 fathoms. The summit area is extensive but irregular, so that there is no evidence of wave truncation. The north slope has a declevity of 14°, compared with 21° for the south slope. Both slopes are slightly concave. All of these seamounts have an appearance which suggests that they are volcanoes which are probably extinct. Such an origin is suggested by the simplicity and symmetry of form, the slightly concave slopes, and the average angle of slope which is always in excess of 10°, but never exceeds 21°. In addition, the seamounts off Baja, California, are located at no great distance from the volcanic Guadalupe Island and in a region of known volcanicity. Yet there is a slight possibility that the seamount shown in Fig. 1B is a south-facing fault escarpment rather than a volcanic mass. The shght asymmetry of the feature and the straightness of the south slope suggests this alternate interpretation. However, although it is difficult in most cases to conceive of any other origin, the volcanic explanation for these seamounts must remain tentative because it is postulated purely on a geomorphic basis. Such criteria for determining the nature of sea-floor features are not well established, particularly when only sounding profiles are available. ‘None of the seamount profiles show any good evidence of terracing or summit truncation such as would result from wave ‘cutting if the seamounts had stood above or near sea-level during a part of this history. This is in contrast with the discovery by Hess(1) that most seamounts in the west central Pacific that rise to depths shoaler than 1,000 fathoms show summit truncation. If the ocean floor has been relatively stable so that summit truncation is to be explained by a former lower stand of sea level, then these seamounts must be younger than those in the region described by Hess. During the Pacific passage the writer was impressed by the paucity of large seamounts. Vast stretches of the ocean showed no sounding less than 2,000 fathoms. Most of the seamounts discovered - are located off Mexico at no great distance from the continent. Existing charts indicate numerous seamounts in this region which show that it has had a volcanic or diastrophically active history. Although large seamounts are rare on these fathograms of the deep Pacific from south of the Mexican area to the Alene ite Ocean, except in the Marquesas Islands region, the eye-ear soundings show that the oceanic floor is rarely smooth, but is, rather, generally rugged and irregular. Ill. Easter IsLtanpd SWELL A profile across the northermost portion of the Easter Island Swell is reproduced in Fig. 2B. Existing charts such as H.O. 2562 show that this swell has a linear extent of several thousands of miles between Easter Island and the Antarctic. This swell is apparently a system of submarine mountain ranges comparable to some of the large cordilleras on the continents, and it must be the combined result of folding, faulting, and volcanism. Soundings obtained by the eye-ear method prior to passing over the swell revealed a flat bottom, with no indication of a foredeep. The profile across the swell shows a general absence of concave 338 aa eee ee eo ee a es a Voce pee sf if Soy 2 | | 5 | ies i - : oa @ a | oi ne Saha ‘ ek 2 Sheree Lov <—— i aC e Cee e se t \ 2 here 1: a y ma i Lo) ae Bi a et cco OT le oes 2°3 x TWOLLNIA Al Mogz="OT Ss teat OTdLOVd “Mm °S ae | “SATIN LAWN | | = es ba Hil “acy ahs INNOVATE s showing a south-west Pacific seamount, the Easter Island .—Fathogram 2 Fic. , and the continental slope of South Australia Swell 339 slopes. The presence of straight and slightly convex slopes suggests faulting and folding. The 30° southern flank of the northernmost mountain is so steep that it is probably a fault-scarp. Here again there is no good evidence of summit truncation by wave erosion. IV. EscARPMENTS A remarkable escarpment (Fig. 3A) was discovered in the Antarctic Ocean about 80 miles north of the Easter Island Swell, to which it may be genetically related. This feature, which has the appearance of a north- facing, tilted fault-block, rises from a depth of about 3,000 fathoms. to a sharp peak at 1,180 fathoms, making a total relief of about 2 miles. Eye-ear soundings obtained prior to crossing the escarpment reveal a foredeep at its base. The fault-face has a straight profile and a declivity of 63°, which is a minimum because, in calculating the slope, it was assumed that the ship traversed the escarpment at right angles. The gentler south slope is straight and has a slope angle of 11°. The steepness of the escarpment, the asymmetry of the feature, and the presence of a foredeep clearly indicate that this feature was produced by high-angle faulting of large magnitude. The absence of effective erosive processes deep beneath the ocean has permitted the preservation of this fault block with “ text-book-like’”’ simplicity. The precipitous- ness of the escarpment probably exceeds that of any continental escarpment of comparable relief. For example, the angle of slope of the eroded east face of the Sierra Nevada fault-block averages about 18°. A second escarpment of considerable magnitude was located during two crossings of a submarine “spur’’ 300 miles in length extending out from the Antarctic Continent adjacent to Princess Ragnhild Coast. Figure 3B shows a profile of this escarpment obtained during the west- to-east crossing. This profile indicates the probable faulted nature of ' the eastward side of the “spur.’’ The escarpment drops with a 44° declivity from 1,100 fathoms to at least 2,700 fathoms, and eye-ear soundings suggest the presence of a foredeep. This escarpment is possibly the result of high-angle faulting or, more likely, by horizontal movement along a fault which has displaced a portion of the Antarctic Continent and formed the submarine “spur.’’ This feature reminds one of the Gordo escarpment off northern California, which, according to Shepard and Emery(2), may have been formed by horizontal displacement of the continental shelf along an extension of the San Andreas fault. V. CONTINENTAL SLOPES During her passage around the Indian Ocean sector of the Antarctic Continent the ‘“‘ Henderson ’”’ remained, for the most part, in the deep water of the basins surrounding the continent. These basins are extremely level suggesting a thick fill of sediments. No seamounts were found. At times the vessel ran along the continental slope at depths shoal enough to be recorded on the echo-sounder tape. Irregular fathograms were obtained, but the presence of submarine canyons or other indentations. into the continental slope cannot be definitely determined because of constant manoeuvring around the ice. There is no detailed record of the changes in course during this manceuvring so’ that many traces which appear to show indentation in the slope may have been produced by changes in course along a smooth slope. 340 vy zest OH MOMd aco TN We X IWOTLEHA @ O0=SE S 24-9 » VOLLOMWINY JdO INANGYYOSS |, ~ ERI ET EN RY FR nn Rd ad > Te | MUCLTES ” PRS SATIN Gee 0 e°7 x TWOLdiha @ €9-SLZT 8 CE-19 ers TTHMS “I YALSVE “N “IN 08 Hise Be ct wor i lie aw CURT LAE 3 RO8 MANE RETIRING Pr kee { eo : ao - ie > s ' : es seater Smomerinen ak Fic. 3.—Fathograms of two Antarctic sea-floor escarpments 341 The “‘ Henderson’ reached the continental shelf of Antarctica only once. On this occasion an excellent profile almost directly up the con- tinental slope was recorded from the Indian Ocean to the Mackenzie Sea (Fig. 4). In comparison with the slopes around other continents of the . world this profile shows a slope that is remarkably long, smooth, and gentle. It has a long, sweeping, concave form, and it varies in declivity from 2° near the top to about one-fourth of 1° at the bottom. There the slope fades into the abyssal sea-floor, 150 miles out from the continental shelf. The smoothness, gentleness, and concavity of the slope give it the appearance of foreset deltaic beds. However, the writer favours the theory of Shepard(3) and others of the structural origin of continental slopes in preference to a sedimentational origin. It is likely that the present form of the slope is the result of extensive sedimentation of detritus carried across the shelf and deposited unconformably along an originally steeper slope. According to this interpretation, this slope can be con- sidered to have reached a physiographic “ old age.’’. The top of the slope is marked by a sharp break at 280 fathoms, shoreward of which isa deep but level continental shelf. This deep break in slope is in marked contrast to the shelves in non-polar regions which generally have their break at about 65 fathoms. The ship traversed about 80 miles of level and featureless shelf before passing again over a sharp break at 280 fathoms. An oblique traverse down the slope to the south-west showed a continental slope similar to that of Fig. 4 and indicated the absence of submarine canyons cut into the slope in this region. An examination of the depth profiles obtained during five other traverses across the break-in slope of the continental terrace obtained by the U.S.S. “ Currituck ”’ on the west Pacific and Indian Ocean side of Antarctica showed breaks at from 230 to 280 fathoms. -Thus this excessive depth of the break-in slope appears to have wide geographic ~ distribution. This may result from deep erosion by glacial ice tongties or by large grounded icebergs. However, the flat nature of the shelf noted in the Mackenzie Sea with a complete lack of irregularities belies ice erosion at least in this area. Hence it is possible that the depth of the Antarctic shelf is explained by isostatic depression of the Antarctic Continent as a unit because of ice loading. Avsecond continental slope profile was obtained when the “‘ Henderson” ran up the continental slope of South Australia from the South Australian Basin into Bass Strait between Australia and Tasmania (Fig. 2c). This slope is irregular and hummocky, with an abrupt change in slope at 550 fathoms. The lower portion of the slope has a declivity of about 2° ; the top portion has a declivity of 6°. The break in slope between the continental slope and the shelf occurs at about 80 fathoms. Judging from published charts, this slope is of normal declivity and form. How- ever, the change in slope at 550 fathoms is striking and is no doubt significant. One possible explanation for this might be that detritus . transported across the shelf also moved down the steep 6° slope and has built up a wedge of sediment at a gentler angle of repose of 2°. The hummocky form of this deeper slope might be the result of landslides or of other mass movements. 342 nd ONIOOLNO | ON, Mecupialore ROAM ales ts OSI Lota dc Ets ; SUTIM IYOTLAYN ; OT 0 £0! / zt X TWOTLYAA AVEDOHLYA NOSUSANTH ssn (VAS BISNUMOWA OLN a Gd0TS WLNANLINOG YOLLOUYING! spaces Aen ta MADE iN E54. Bees S169 = 990 ee ie Sea Fre. 4.—Fathogram of the continental slope of Antarctica near the Mackenz 343 VI. CONCLUSIONS The development of the continuously recording echo sounder makes possible much more detailed studies of sea-floor geomorphology than was possible in the past. However, echo-sounder records still have many limitations such as generalizing the bottom because of the poor directivity of sound so that fathograms must ‘be interpreted with caution. It is also unfortunate that standard echo sounders have a tape recording limit of 2,000 fathoms as nearly all of the ocean floor is located at depths in excess of this. In studying sea-floor features from fathograms one is generally assisted by a simplicity of form resulting from the absence of competent erosion processes like those which add greatly to the complexity of subaerial features. It follows from the lack of erosion that some sea-floor features are extremely old, perhaps as old as the ocean basins themselves. Such physiographic “‘museum pieces’’ are in contrast to subaerial geomorphic features which are generally considered to be entirely late Tertiary or younger. REFERENCES (1) Hess, H. H. (1946): Drowned Ancient Islands of the Pacific Basin. Am. Jour. Sci., Vol. 244, pp. 772-791. (2) SHEPARD, F. P., and Emery, K. O. (1941): Submarine Topography off the California Coast. Geol. Soc. Am. Special Papers No. 31, pp. 35-41. (3) ——— (1948): Submarine Geology. Harper and Bros., New York, pp. 193-194. Ht GROLOGYS OF BEGIN IARSHALE ISEANDS By H. S. Lapp and J. I. TRacry, U.S. Geological Survey (Read by Dr. K. O. Emery) [A bstract| Soundings have been carried out on the sloping shelf around Bikini, and the slope indicated was relatively steep. A seamount was also indicated lying to the north-west. The projections of the reef are reflected in projections at depth. Soundings around the Rongelap Atoll also indicated steep shelves and an associated seamount at Eniwetok Atoll. A deep terrace at 750 fathoms lay to the north-west and a similar one to the south-east. North of Bikini is a shallow seamount which was illu- strated in some detail. Deep-sea sediment distribution was illustrated on plan. Deeper sediments are red clay, but at 2,300 fathoms to 2,000 fathoms it is replaced by globergina ooze, and between this zone and the atolls there is a variety of sedimentary types. Sonic soundings around Bikini indicate a slope of a maximum of 45°, and close soundings were carried out adjacent to the atoll with leadline. Cross-sections of atolls and seamounts were illustrated. The former indicated steeper slopes at the atoll, but the latter had a somewhat different profile which was comparable up to 600 to 700 fathoms, and above that a decrease in slope or a rounding off. Sounding within the lagoon itself indicated a terrace around the perimeter, widest at the outward projections and narrowest at the inward projections. The subsidence theory may hold ground for atolls built up from the seamounts, but this would require a deep drill-hole to prove. At Bikini there had been planing at lower sea-levels during glaciations. Growth of the rate of coral is estimated at 1mm. per year from the reef surface. There was a marked concentric distribution of sediments within the lagoon itself. o44 SUMMARY OF DISCUSSION Professor Yonge stated his experience on the Barrier Reefs off Queens- land, where the coral grew in confused masses, and, under heavy seas, it was broken up and piled up on the reef, and on other parts of the Barrier the reverse took place, and broken material formed submarine talus slopes. In answer to a question concerning light-penetration, Dr. Emery stated that some measurements had been taken, and that light seemed to be effective 150 to 180 ft. in the lagoon, and apparently this was the same outside the reef. Dr. P. Marshall remarked that the distribution of organisms and sediments described was very similar to that observed at the Cook Islands. MIO Da SNPS Oh ribs SP Aw ING POsl-=GUACIAL. TIMES By Ruopes W. FarRBRIDGE, University of Western Australia In his memorable work on the most recent eustatic drop in the level of the sea Daly (1920) reckoned on something of the order of 20 ft. and collected from the world-wide literature, willy-nilly, it might seem, all references he could find to “ fairly recent *”’ raised beaches, terraces, and the like. More than adequate evidence is now available to indicate that quite a number of Daly’s levels really belonged to a late Pleistocene date (possibly Zeuner’s “ late Monastir ”’ level, approximately 25 ft. in the type area of the Mediterranean) and identified far and wide in the Pacific (see Stearns, 1941, &c.) and other oceans. On the other hand, the various lower figures obtained by many workers have rashly been discredited altogether by the late Professor Douglas Johnson (1933), who decided that all marine erosion surfaces below “ hurricane-beach ”’ height were the products of the present cycle of erosion. The wide experience of and many papers by Stearns (1941, 1945, &c.) should be sufficient demonstration that in fact some of these lower levels are truly eustatic. Stearns and others attribute them to a mid-Recent stand of the sea at 5 ft. above the present. In certain particularly favoured areas, however, it has been possible to recognize not one, but for distinct stands of the sea in post-Glacial times. Kuenen (1933) found these in the East Indies and placed them at 4-5m., 13-2m., and 4-1 m. above the present sea-level, which con- stitutes the fourth and latest stand. Working independently, the author and C. Teichert have lately found very similar traces in Western Australia (10-11 ft., 5-6 ft., 2-3ft., and the present zero-level bench). These were first recognized in the Abrolhos Islands (Fairbridge, 1948) and on - Rottnest Island (Teichert, 1948), and we have both followed out the evidence together up and down the very stable coast of Western Australia for nearly 1,000 miles. Further evidence from islands and mainlands bordering the Indian Ocean and elsewhere suggests that these indicate truly eustatic sea-levels. This was suggested already over a century ago by Ehrenberg (1834). Comparison with recent studies in Sweden suggest that they have all been completed during the last four thousand years. The highest sea-level appears to correspond with the “ Atlantic ’”’ phase of climatic optimum (Flandrian stage of Dubois). The fact that these terraces are horizontal in attitude and separated from one another by short vertical cliffs, with other evidence, has led to the conclusion that periods of stand-still were protracted, but that changes 345, in level were carried out in a very short time (probably less than a century for a 5 ft. drop). The sea-level appears to have suffered short, sharp drops (Fairbridge, 1949) ; there seems to be little hkelihood of any oscilla- ting up and down below the present sea-level in these post-Glacial move- ments. Several factors may be combined to explain the remarkable development and, consequently, the discovery of these benches. First, there is a very small tidal range on much of our Western Australian coast-line, and likewise in the East Indies and elsewhere in the Indian Ocean. A neap rise and fall of less than 12 in. is normal at Fremantle. This means that at any rate the terraces at 5-6 ft. and 10-11 ft. above datum (low-water springs, which is the level of the contemporary bench) are generally clear of actual marine erosion and are only being slowly attacked by spray and rain. Shells in the associated raised beaches often still maintain much of their original colour. Secondly, off-shore reefs and wide fringing reefs protect much of our coast-line from storms. Hurricanes are not experienced. The benches are, of course, found best preserved in protected bays, inlets, and lagoons. Thus, in the Abrolhos Islands, the broad lagoon is flanked by low cliffs, in which here and there may be found all four levels rising in steps. On Rottnest a series of inlets, which were open to the sea until a few centuries ago, have now been sealed off by advancing sand-dunes to form a series of salt-lakes. The cliffed margins of these lakes now exhibit the most beautiful series of undercut notches, benches, and raised shell-beds which it has ever been my good fortune to see. Such perfect preservation is, of course, not found everywhere ; it would hardly be reasonable to expect to find a 2-3 ft. terrace preserved from the present attack of the sea in any but exceptional places. Normally this low terrace is completely destroyed or reduced to a sloping ramp which leads up into the. 5ft. notch. In exposed spots the contemporary 2 ft. and 5 ft. notches are all smoothly graded into one and only the 10 ft. bench stands out like a visor above the contemporary terrace. The third factor of importance in making these West Australian benches so striking is the fact that they are all cut in limestone. In places it is a coral limestone, or a massive lagoon limestone, but generally it is a sandy calcareous eolianite. All are of Pleistocene age, but generally extremely indurated and hard. The nature of limestone, as I have tried to indicate already (Fairbridge, 1948, 1949), is particularly favourable to the formation of a very massive, yet clean-cut, marine platform at exactly the height of low-water springs. This level is the critical lowest limit of subaerial erosion and also is close to lowest limit of super-aerated surf. The latter is rendered temporarily acid in its reactions to limestone under certain bio-chemical and physico-chemical conditions (extemely variable temperatures, CO, and pH ranges). With the sharp changes experienced in this zone limestone is alternatively dissolved (tending to reduce the level of the land to a horizontal plane coinciding with low-water springs), and alternately precipitated (pro; ducing a travertine filling in all the interstices of the limestone and rendering the rock so massive and hard that it rings to a hammer blow and was even used by primitive man for “‘ flint ’’ artifacts). The result is a horizontal bench of extreme resistance. It is realized that purely biological and mechanical factors are also highly active in this same 346 inter-tidal zone, but are not considered to be of the same significance as chemical erosion. Research into these various operations is still proceeding. The scientific consequences and implications of these discoveries may be of considerable interest to geomorphologists and archeologists. If the levels themselves are truly eustatic—z.e., world-wide—and if the four changes in level have actually taken place along the coasts near settlements of classical antiquity, such as Egypt and Mesopotamia, then important correlations may be worked out. An interesting essay in this direction was made by H. W. Pearson already in 1901, but this and other early attempts are full of weaknesses due to uncritical reading of evidence, to a failure to recognize the full complexity of the problem, and so on. Finally, looking to the widespread coral islands of the Pacific, it would be surprising indeed if further intensive study here also did not reveal traces of these most recent strand displacements. BIBLIOGRAPHY EHRENBERG, C. G. (1834): “ Ueber die Natur und Bildung der Corallenbanke des rothen Meeres. Phys. Abhandl. k. preuss. Akad. Wiss. (Berlin), for 1832, p. 381-438. Davee, R. W. (1948): Notes on the Geomorphology of the Pelsart Group of the Houtman’s Abrolhos Islands.. Jouvn. Roy. Soc. West. Aust., Vol. 33 (for 1946-47), pp. 1-43. (1949): The Geology and Geomorphology of Point Peron, Western Australia, Journ. Roy. Soc. West. Aust., Vol. 34 (for 1947-48), No. 3. (In the ‘ press.) Jounson, D. W. (1933): Supposed Two-meter Eustatic Bench of the Pacific Shores. C.R. Congr. Int. Geogr. (Paris), Vol. 2, pp. 158-163. KUENEN, P. H. (1938): Geology of Coral Reefs. The Snellius Expedition, Vol. V, Geological Results, Pt. 2, 125 pp. Pearson, H. W. (1901): Oscillations in the Sea-level. Geol. Mag., Dec. IV, Vol. 8, pp. 167-174, pp. 223-231, and pp. 253-265. STEARNS, H. T. (1941): Shore Benches on North Pacific Islands. Bull. Geol. Soc. Amer., Vol. 52, pp. 773-780. TEICHERT, C. (1948): “Late Quarternary Sea-level Changes at Rottnest Island, Western Australia. Pyvoc. Roy. Soc. Vic., Vol. 59 (2), pp. 63-79. MARINE EROSION By Ruopes W. FAIRBRIDGE, University of Western Australia OBSERVATIONS on the nature of marine erosion, resulting in the formation of contemporary marine benches, platforms, terraces, or reefs around the shores of the Pacific, Indian, and Atlantic Oceans have puzzled the writer for some time. Investigations into the relative effects of chemical, biological, and mechanical erosion here have led to conclusions which concern the whole nature of marine erosion, ranging from the emergent “wave-cut ”’ terraces, which fringe so many Pacific islands, to the broad floor of the continental shelf. : THe “‘ NORMAL ’”’ SHORE PROFILE Reading that the normal shore terrace was theoretically part of a profile of equilibrium achieved by mechanical erosion operating to wave- base (according to the Gulliver, Fenneman, Davis, Johnson school), it is somewhat astonishing to find in reality that the most usual profile of the continental margin 7 the more stable parts of the earth is in fact a series of steps, either sloping gently outwards or often even more or less 347 horizontal (see the many recent papers on continental shelves and submarine terraces). These observations have been based mainly on a study of the more recent hydrographic charts (many of which are based on very accurate sonic sounding). Notice that emphasis is placed on the phrases ‘‘ most usual’’ and “ more stable,’’ because the following remarks hardly apply either to entirely new shores, such as those of a freshly erupted volcanic island, or to the rapidly emerging shores of formerly glaciated areas which had been isostatically depressed, or again to highly mobile shores in the grip of active tectonic movement. In short, I am thinking of the normal coasts of the stable parts of the Continents of Australia, Africa, America, &c., but, nevertheless, the - conclusions may also be seen to apply to many of the younger shores as well. The general consensus of opinion now indicates that most continental shelves were, at least superficially, sculptured by shore-line erosion during the Pleistocene into series of platforms at various levels. The question of the degree to which glacial lowering of sea-level or tectonic oscillation of the continental border contributed this eventual result need not con- cern us for the present (cf. Lewis, 1937; Novak, 1938 ; Bourcart, 1938 ; Umbgrove, 1946; Fairbridge, 1946, 19474, 1948). Thus, for example, the continental shelf off Western Australia appears to consist of a series of terraces at 3-5, 10-15, 25-30, 55-60, and at about 100 fathoms below sea-level. Other stable coasts exhibit very similar features. We must conclude that no such thing as a mature offshore profile of equilibrium exists to-day, since major changes of sea-level, ranging through the Tertiary and Pleistocene, right up till to-day, have kept the profile in a continuous state of alternate rejuvenation and drowning. It is apparent that the few thousand years, which have elapsed since the last major submergence of the continental shelf have not been a sufficient span of time to permit mechanical erosion at wave base to reduce the ruggedness of these submarine terraces to a smooth profile ; sedimentation may be helping to fill up some of the depressions and round off the contours, but the essential sharpness is still there. The power of waves and currents to sort and distribute loose sediment across the shelf is undoubted, but a serious question is raised as to the strength of waves and currents to rapidly erode hard rock outcrops at depths ct, say, 10-100 fathoms. HoRIZONTAL PLATFORMS My problems really started when I noticed that the average “ wave- cut” platform of to-day is generally steep-to on the outside edge and is essentially horizontal on the surface. This means that the platform does not slope gently outwards to merge into the off-shore profile that descends to 100 fathoms or so, as we would have to believe from text-book figures (e.g., Johnson, 1919-88, Fig. 37). A soft, sandy, or muddy coast may well be endowed with a gently sloping off-shore profile, but not a rocky coast ; in fact, I have the impression that the cliff foot on the average rocky coast is being eaten back more rapidly than is the outer margin of the platform (see, for example, Gill, 1949) ; the older the coast (7.e. the longer it remains stable in relation to the sea-level) the wider the platform will become. Such a conclusion is hardly in conformity with the ““ traditional ’’ teachings of the Johnson school of marine erosion. 348 Such contemporary horizontal platforms may be seen par excellence in the Pacific and around the shores of Australia. These regions are endowed with widespread limestone coasts, which, because of their solubility in sea-water in the inter-tidal belt under certain highly special- ized bio-chemical and physico-chemical conditions on the warmer reef- flats, are particularly favourable to the rapid erosion of these broad horizontal platforms. It makes no difference whether the limestone in question is of coral origin or is a massive chemical rock, or yet again is the sandy calcareous eolianite commonly found on more arid coast-lines. In certain favoured places these contemporary platforms range up to half a mile in width ; in others perhaps only a few feet. Normally they are horizontal, though the outer part may be undercut and slope away ; or it may have an elevated rim. The inner part may be truncated sharply by cliffs; or again it may rise in a gently sloping ramp, particularly so in exposed places where there is a considerable swash. It should, however, be emphasized that horizontal reef platforms are also found in rocks other than limestones, such as shale, sandstone, schist, and so on, but massive rocks like granite and basalt are so resistant to subaerial and intertidal weathering that, in the limited time available since the last eustatic change of sea-level (possibly less than one thousand years), no appreciable benching has occurred in them. There are thus ideal bench-forming rock types, and others which are not at all favourable. The explanation of this horizontal benching has been sought with considerable curiosity. Investigations are still in progress. But this much at any rate is clear: as Bartrum, in New Zealand, has already very satisfactorily demonstrated, subaerial erosion operates rapidly and deeply on many rock-types, but is arrested in depth by sea-level, for alkaline sea-water acts as a preservative for most rock materials, in contrast to the destructive character of acidic rain-water. Thus, below the inter-tidal belt, the erosive action of the sea is negligible in contrast to that of the atmosphere; the critical zone of erosion is in the inter-tidal levels, where rock materials, loosened and_ partially disintegrated by subaerial forces, are etched, abraded, quarried, and washed away by the surf. In this same critical surf zone certain curious temporary chemical changes take place. Although sea-water is normally alkaline, here the action of the surf causes large amounts of CO, to be taken into solution, thus lowering the pH and rendering the water and spray temporarily “acid ’’ and thus corrosive. Drop in temperature in the water on the reef flat at night and, in the absence then of photosynthetic removal of CO, by plants, normal respiration of plants and animals in the inter- tidal area will all tend to the same end—that is, an increase in acidity, The relative importance of each factor is yet to be worked out.' (1) I have recently come across a reference which helps to, explain the unfavourable reaction of certain rocks to bench-forming processes. Half a century ago J. Joly, of Dublin, carried out careful experiments which demonstrated that aerated sea-water dissolved various silicate minerals and igneous rocks much faster than did fresh water similarly aerated. Hornblende is “eight times ; orthoclase fourteen times; obsidian four times; and basalt three times more soluble in salt than fresh water. (Joly, J. (1901): ‘‘ Expériences sur la dénudation par dissolution dans l’eau douce et dans l’eau de mer.”’ C.R. Congr. Geol. Int. (VIII, Paris, 1900), Vol. 2, pp. 774-784.) Naturally there is greatest aeration (acidity) of the sea- water in the intertidal zone, so that one would naturally expect some sort of bench to form, but the solution also goes on below this belt, so that one would not look for quite the same sharp outlines found on the ordinary benches. 349 The precise elevation of this contemporary horizontal platform is a matter of considerable importance. From my own and others’ observations (see Macfadyen, 1930; Kuenen, 1933; Fairbridge, 1948 ; Fairbridge and Gill, 1947; and many others) it is claimed that the “normal’’ platform forms at the level of low-water springs. Exceptions are known ; pre-existing cavities in the rock (karst caverns and holes), lenticles of soft sand in the country rock, collapse structures, and so on, may all cause segments of the reef to be “ abnormal.’’ The occurrence of hard rock bands, gently dipping, may come by differential erosion to almost conform to the ideal reef height and shape, but may exhibit a gentle dip in one direction or another; the effect being to institute considerable confusion (see, for example, the Sydney benches in gently- dipping Trias sediments—Jutson, 1939). Very exposed positions may result in shore “ramps, where the bench slopes gently up on the inside owing to the nature of the swash profile. However, when viewed overall, the “‘ abnormalities ”’ find local explanations, while the “ normal ” bench elevation tends finally to the height of low-water spring tides. An interesting problem in this connection was first described from New Zealand by Bartrum (1916, 1935), where his “ Old Hat” bench was already recognized by Dana and by Hochstetter. Its elevation is just below high-water level. Bartrum assumed that this is a contemporary bench, formed at the present stand of the sea, but in rocks of a particularly favourable sort and in fairly protected places; the rock below high-water level is supposed to be always saturated in protective sea-water, while the overlying rock is subaerially weakened and prepared for removal by quite gentle waves. I cannot agree with this interpretation, and feel that the base-level of subaerial erosion is not high-water, but low-water, springs; also the major role played by inter-tidal chemical processes should not be forgotten. Personally, I regard the “Old Hat” type of bench as a perfect example of the 10 ft. eustatic platform which was actually formed only about four thousand years ago, and is thus preserved in a surprisingly fresh state in favourable locations. Admittedly, if we had not had the privilege of examining the phenomenon on many occasions under ideal conditions on limestone shores we might very well have failed to realize that there had been multiple eustatic stands of the sea-level during the last few thousand years, which have had the result of producing platforms a few feet above the present one—that is, at 2-3, 5-6, and 10-11 ft. above datum (for example, the present low-water spring-tide level (see Kuenen, 1935 ; Fairbridge, 19474, 1947B, 1948, 1949; Teichert, 1947, 1948) ). It may thus be readily perceived that in regions of considerable tidal range, as in New Zealand around Auckland, all three of these higher benches would still be subjected to marine erosion to-day, and, in fact, may be very easily attributed to the effect of the sea at its present stand. In this way de Lapparent in France (1906), Jardine in Queensland (1925), Jutson in New South Wales (1939), Edwards in Victoria (1941), and Bartrum in New Zealand (1926, 1935) all speak of marine erosion as if it were selective at different heights of the tide and states of weather. At low tide we are supposed to get a “ normal ” or ‘‘ ultimate ’” bench, at mid to high tide we find an “ Old Hat ” type of bench, and, finally, at storm-wave swash-height we see a notch called a “storm-wave”’ bench. In a quiet bay in Western Australia, however, I believe I could demonstrate all four levels in one and the 300 Waa k - | r : —— 2 = — J oS 3BNMAL GadAivus9090Vx2 BIWIS WwWIILYUIA “GA'N wap BS NZ 0° ooe Fy) oO" a mapa 1 4 a foes 4334 Ni S1v2s IWANOzINOH ™ AWD TMH 4 oe att Ws, ot oe Ze ZE | Ree ah Press A wy 3 0) GAZ a 3 } a? ag i << 30) fu SN } SS poo” Jt 91 SN yo? dv 08" YTS y fy ~ : RX UN S4AWIL OF G32LVESIIVARS 31W9S WI143A “BN d — 192) fis Poodiod of yw a3? ) wha ny 9222 s | oP Det IAIN et TIAJT YILGM MOT — JPAITAILYM HOIH Idealized section of a limestone reef flat, indicating how extreme physico- chemical conditions over the reef flat may facilitate chemical solution of the limestone down to the level of low-water springs, and operate at a maximum (in protected places) at mean sea-level, producing a deep undercut Fic. 1p.—Idealized section of the JOnNwe QD ONY NOILVIYWA Ialxord NOBUv? BR FJONLVSFANIL LNVLSNOD ONY |. FANLWAHIAWIL Ne Se x ene Alav3#N 40 vay YILVM L4SFLVFHVD FO YI soe” ay? H waivM d 33d Avis 4334 Oo 38 a y b4%o0 : Q)*)0 pid: ie yor’ 724 cliffs at Point Peron, ” “coastal limestone 351 Western Australia, showing four post-Glacial bench levels cut by the sea at its various stands Fic. la. same place, a spot where storm-waves never reach and where the tidal range is so small that all the higher benches or notches are practically preserved from wave erosion (Fairbridge, 1948, 1949; Teichert, 1948). Taking the matter from another point of view, if we recognize that there have indeed been Recent higher sea-levels, we would expect to find the appropriate benches of those stands ranging up above the present “ Old Hat ”’ or storm-wave platforms. But, curiously enough, we do not. In places of considerable tidal range to-day, however (say, anywhere in excess of 10 ft. spring range), I would not be surprised if all the inter- mediate benches and notches are destroyed, so that all we see to-day is a single, large notch, the maximum incision of which stands at 12-15 ft. above present datum. This is a relic of the 10 ft. sea-level, with limited modification by all subsequent stands. It seems thus very likely that the ‘“ Old Hat ” bench of protected waters in New Zealand is also the product of the 10 ft. sea-level ; its resistant surface is not due to contemporary saturation by sea-water, but to induration at low-water level in early Recent times. And the “ storm-wave’’ notches, which rise 5-10 ft. higher, are products of the same high sea-level, but in more exposed places. For these reasons I am inclined to think that all the varied types of platforms attributed to contemporary marine erosion are nothing but “normal” platforms of various former sea-levels, some of which were broad and some were narrow and easily effaced, and which are subject to-day to varied exposures and types of weathering. SOME EARLIER POINTS OF VIEW The initial conclusion is that marine erosion on rocky coasts is very different from the text-book picture. We find a horizontal rock bench, tending towards an ultimate plane at the height of low-water spring tides. This is the base-level of subaerial decay. The mechanism of the erosion is more subaerial than marine, more chemical than physical. Wave action seems relatively unimportant below a few fathoms depth. Some investigation of the literature indicates that this is not really a new discovery, but merely that early work of the “ chemical school ”’ has been forgotten. I find the contrast between the two schools of thought on the subject of marine erosion—.e., the chemical versus the mechanical— so astonishing and so fundamental that a few appropriate quotations might be illuminating :— Ramsay (1846), while being largely responsible for the theory of mechanical marine denudation, which was first outlined by de la Beche, conceived a platform of mechanical marine erosion which reached down only to a moderate depth; nevertheless, he expressed the opinion that subaerial erosion was a vital aid to marine planation by wave action. The term “abrasion ’’ was coined for the mechanical process by von Richthofen (1886), who developed the idea further. Lyell (1865) would consider the mechanical explanation and no other, saying, ““ No combination of causes has yet been conceived so capable of producing extensive and gradual denudation as the action of the waves and currents of the ocean upon land slowly rising out of the deep.” Crossing the Atlantic, the teachings of Lyell appear to be reflected to some extent in the way in which the early American physiographers, such as Gulliver (1899) and Fenneman (1902), Davis (1909, &c.), Barrell (1918, &c.), and others make no mention whatever of subaerial agency in shore-line erosion. Summarizing the conclusions of this school, 302 Douglas Johnson (1919/1938) states bluntly: “The vertical limit of marine denudation is a surface so low that wave action is no longer retarded by it ’’ (a depth of 600 ft. or so in his opinion), and he finds the corollary that “ there is no horizontal limit of marine erosion ”’ (p. 234). Returning, however, to the English physiographers of the last century, in specific reply to the wave enthusiasts, G. Maw (1866) expressed the opposite with precision and clarity. He was struck first by “ the level surfaces of sea-coast reefs,’ indicating the base-level of rapid coast erosion at sea-level; the logical conclusion, of course, was that “the sea does no material work below the tidal range,’’ except, of course, in certain very exposed places. The general tendency of marine erosion is towards a straightening of a coast-line, while drowning institutes indentations formerly occupied by subaerially formed valleys. Maw’s accurate description of the normal contemporary horizontal bench or off-shore reef in England is a model which to-day could hardly be bettered elsewhere: “If we examine the sea-bed between high and low water mark, on any cliff-girt shore it is impossible not to be struck with the singularly level disposition of the reef surfaces extending seaward, which once formed the foundations of the old cliffs. Their general height would be a trifle above that of low tide, and any irregularities of surface will not exceed one or two feet. This well-marked lower limit to the erosive action of the sea is not confined to hard rocky coasts, but will be found to hold good in the softest strata.”’ The same thing was realized, too, by W. Whitaker (1867), who con- eluded: ‘‘ The sea, therefore, does not by itself destroy the land, but is largely helped by atmospheric actions.’ Mellard Reade (1885) agreed, but claimed in fact that this was thoroughly understood by Hutton already a century before. On a previous occasion (1877) Reade had outlined his chemical experiments and calculations, concluding: “ The chemical agency decomposes the matrix. . . . The ocean acts merely as a mechanical distributor of matter. . . . The action of subaerial erosion is . . . unlimited, except by sea-level.” Again, it is interesting to quote A. H. Green (1882): “ The sea toa very large extent only finishes the work begun for it by subaerial denu- dating agents” (p. 206), and “It must be noted that the destructive action of the sea is confined almost entirely to the belt between high and low water mark. Within that space the rise and fall of the tides and the forces of the breakers grind down any loose matter exposed to their action. These agencies, however, cease to have any effect on the bottom covered by a moderate depth of water, and hence very nearly all the denuding work of the sea is coast denudation. The drifting of the rough sediment over the bottom by under-currents may produce some abrasion, but its amount cannot be very much ”’ (p. 207). And yet again, Jukes- Browne (1898, p. 135): ““ Sea-waves can only act along one plane, and its currents, though able to erode soft sands and clays, can make but little impression on more solid rocks.’’ And earlier, in more detail, he suggested that low-water mark was the lowest limit of subaerial forces; it was in fact “a line of non-erosion ’”’ below which accumulation would normally begin. “‘ On a rocky shore the tendency of these conditions is to produce a horizontal or gently sloping platform, the outer edge of which corres- ponds to the line of non-erosion, so that its surface is bare at low water ” (1884, p. 120). ’ In America, too, the same concept was expressed. J. D. Dana (1880, p. 676) says clearly: ‘The lower limit of erosion is above low-tide level.” And, “ The wearing action of waves on a coast is mainly confined 303 to a height between high and low tides,” though in this case Dana does not mention subaerial action. It is not without significance that Dana had travelled the Pacific extensively, including Australia and New Zealand, while Gulliver, Davis, Barrell, Johnson, and others formulated their ideas on the isostatically unstable, and therefore abnormal, coasts of New England (which are suffering post-Glacial reactions.) Even Sir Archibald Geikie (1903, p. 575), while strongly emphasizing the forces of mechanical marine erosion, was careful to point out that : ““ Were it not for the potent influences of subaerial decay, the progress of the sea would be comparatively feeble.’ In Norway, recognizing the efficacy of subaerial erosion, Nansen (1905) believed that only such loosen- ing and weakening could break down the extremely hard metamorphic (Caledonide) rocks, enabling the waves to move the debris to form the famous “‘ Strand-flat.”’ Actual observations by W. von Zahn (1909) on the rocky coasts of Brittany and Normandy disclosed two distinct zones above and below mean sea-level: a “ Schliffzone’’ or ““Smooth Zone’’ below, affected by mechanical erosion ; anda “ Spritzzone,”’ or “ Brandungskarrenzone ”’ (Spray-etched Zone), above, affected by chemical erosion. Kayser (1923) ~ pointed out in any case that all three processes of purely marine erosion, biological, physical, and chemical are restricted to the absolute upper limit of marine erosion, and therefore tend to cut horizontally. The rather special position of limestone in relation to chemical solution, as indicated above, has long been recognized, though exaggerated by Murray, Agassiz, Gardiner, and Crossland. Rapid solution of limestone in ordinary open sea-water certainly does not take place beneath the surface. On the other hand, recent observations by Macfadyen (1930), Kuenen (1933), and Fairbridge (1948) show conclusively that chemical erosion of limestone is accomplished by physico-chemical and/or bio- chemical processes of sea-water in its surface few inches near the shore. In this way broad, flat marine benches are eroded, the level of which is at the low-tide limit. Maximum erosion, in protected places—.e., where the actual sea-level is not mechanically raised by wave action— is at mean sea-level, and cliffs are deeply undercut at this level. As Kuenen says: “ The solvent action is limited between the tidal range. The action of the sea is that of ‘sawing’ into the limestone.” Apart from the exceptional position occupied by limestone in this broad picture, the weakness of ordinary rocks to subaerial decay and their resistance to submarine mechanical attack has been specially emphasized by workers in New Zealand, where particularly fine examples of various benches were exposed. Noted in very early times by Dana (1849, 1872, 1880), a thorough explanation appears to have been first suggested by E. de C. Clarke in 1909: “ Rock-benches are developed in many places along the steeper parts of the shore-line, more commonly in the sedimentary rocks, but also in the volcanics. These benches consist of shelves cut out of the solid rock, generally horizontal : it seems possible to ascribe the formation of rock benches to the co- operation of subaerial weathering, which causes the retreat of the cliffs; with marine transport, which removes the waste so-formed ” (in Bell and Clarke, 1909, p. 30). Bartrum has greatly developed this research into the New Zealand benches, and while I fancy that he did not fully appreciate the significance of eustatic changes, he clearly recognized the importance of subaerial weathering above sea-level. While the lower part of the 304 cliffs, being permanently bathed and saturated in sea-water, would be completely protected from subaerial weathering, quite gentle waves would be sufficient to remove the debris, resulting in wide, flat benches (1916, 1935). | : PENEPLANATION Thus we see that it was a very different thing to imagine the sea operating mainly as a mechanical (and locally chemical) removal agent in the inter-tidal belt, from having its active mechanical erosion reaching right down to the ultimate wave-base. The sea could not act as an agent of regional peneplanation according to the former concept, but could according to the latter. With the former, the horizontal platform of erosion would eventually grow so wide that the sea could no longer wash away the debris but with the latter the waves would continuously be working downwards, permitting powerful waves to reach the cliff. It was this stumbling block which brought Douglas Johnson up against the old teachings of Ramsay, von Richthofen, and many others—e.g., de Martonne, de Lapparent, Kayser, including Gulliver and Scott, in his own country, to name only a few outstanding names. De Martonne (1934, p. 671 e¢ seg.) refers in fact to the Ramsay-Richthofen school versus the Barrell-Johnson school. The former believed that marine erosion acting on a stable continent would eventually form such a broad shallow abrasion platform that it would come to a standstill. The Johnson school imagined that an entire continent might in time be reduced to a submarine peneplain. To quote Johnson’s own words (1919, and even in his revised edition 1938, p. 163): “ If a land stands still long enough, the waves will reduce it to an ultimate abrasion platform . . . no matter how great may have been the original extent of the land.” Theoretically true J perhaps, but R. T. Chamberlin (1930) has shown that if all the lands were base-levelled in this way the sea-level would rise 670 ft. ; so the production of such a horizontal peneplain is in any case impossible. This Johnson concept is utterly unacceptable to de Martonne (1934, p. 677) and most continental European students. De Lapparent made the interesting suggestion that since wave action is far more impressive on the stormy coasts of Great Britain (and we might add Johnson’s own New England shore-line) they should not automatically be regarded as normal (De Lapparent, 1906, p. 242). Even then he contended that the “normal” platform of marine erosion only ranges from high to low-tide. level, though he called in storm-wave seasons, &c., to account for series of terraces (a phenomenon now adequately explained by eustatism). Park, in New Zealand, also made this point (1925), indicating that subaerial solvents provided a “ powerful ally” to the “ more apparent’ forces of mechanical erosion. In complete contrast to the fundamental teachings of the Lyell- Johnson school, the recognition of the slowness of marine erosion has apparently always been made in Europe. More recently, Novak (1938), Bourcart (1938), Francis-Boeuf (1938), and others have concluded that the continental shelf could not be due any more to Johnson’s marine erosion than it could be exclusively due to Sir John Murray’s sedimentary explanation (1888). Being left with subaerial erosion as the only satis- factory answer to the abundant evidence now available, from the topo- graphy (shown by sonic sounding), from the numerous basement rock 355 outcrops, and so on, scientists are now looking for suitable explanations for this subaerial exposure, or successive exposures, of the shelf. Glacio-eustatic and tectonic explanations are both favoured, and a whole new field of instructive research is now opening up. These two schools, therefore, thanks to the localities of their active protagonists, have more or less become associated to-day with Britain and America versus continental Europe. Since Johnson’s influence, for innumerable well-justified reasons in other connections, has been widespread in North America, his theory of marine abrasion has there become accepted almost without question. It is fortunate, however, that doubts have also been expressed on that continent. Wentworth (1927), as a result of careful studies in Hawaii, came to the conclusion that marine erosion cannot be a factor in pene- planation, only subaerial erosion could perform this colossal work. As a result of these and other researches considerable doubts are nowadays being expressed on the matter. Attention has also been drawn to another great fundamental weakness in all Douglas Johnson’s coastal work, his omission to recognize fully the ever-riding control of eustatic changes which in Pleistocene and Recent times gave rise to multiple oscillating strand-levels (Shepard, 1937). Johnson (1933) made exactly the same error as many others in the Pacific in mistaking the 10 ft. eustatic bench as a storm-wave platform ; this is the same bench that is so commonly found all.around closed bays where storm-waves mever reach. In conclusion, to summarize these remarks, we have made a protest against accepting the dogma laid down in many of the standard English and American text-books, following the teachings mainly of Lyell and Douglas Johnson, which appear, thanks, no doubt, to the geological constitution and geographical positions of the British Isles and the rugged coasts of New England, to have grossly exaggerated the forces of mechanical marine erosion and ignored the processes of subaerial and chemical decay in the formation of coastal benches or terraces. The works of European physiographers and those of New Zealand have been sedulously disregarded in this connection. Finally, we deduce that the submerged and terraced shelf regions of the Pacific and other oceans are not the result of mechanical erosion operating to wave-base, but were cut subaerially and in the inter-tidal belt during periods of low eustatic sea-levels (or tectonically elevated continental rims). The short time that has elapsed since that last great — emergence has prevented the accumulation of more than a thin veneer of post-Glacial sediment. BIBLIOGRAPHY Bartrum, J. A. (1916): High-water Rock-platforms: A Phase of Shore-line Erosion. Tvans. N.Z. Inst., Vol. 48, pp. 132-34. (1926) : “‘ Abnormal ” Shore Platforms. Journ. of Geol., Vol. 34, pp. 793- ee. (1935) : Shore Platforms. Rept. Aust. & N.Z. Assoc. Adv. Sct., Vol. 22, p. 135-148. ; BELL, J. M., and CrarkeE, E. DE C. (1909) : The Geology of the Whangaroa Sub- division, Hokianga Division. New Zealand Geol. Surv., Bull. No. 8, (n.s.), 115 pp. Bourcart, J. (1938): La marge continentale. Essai sur les régressions et trans- gressions marines. Bull. Soc. Geol. Fr., 5 ser., Vol. 8, pp. 393-474. CHAMBERLIN, R. T. (1930) : The Level of Baselevel. Journ. of Geol., Vol. 38, pp. 166-173. Dary, R. A. (1920): A Recent World-wide Sinking of Ocean-level. Geol. Mag., Vol. 57, pp. 246-261. 306 Dana, J. D. (1849) : United States Exploring Expedition 1858-42, Vol. 10 (Geology). (1872) : Corals and Coral Islands. London (2nd. ed., 1875). (1880) : Manual of Geology. New York, 911 pp. Davis, W. M. (1909) : Geographical Essays. Boston. Epwarps, A. B. (1941): Storm-wave Platforms. Journ. of Geomorph., Vol. 4, : pp. 223-236. FaiRBRIDGE, R. W. (1946) : Coarse Sediments on the Edge of the Continental Shelf. Amer. Journ. Sci., Vol. 245, pp. 146-153. (1947a) : Our Changing Sea-level. Scope (Journ. Sci. Union., Univ. West. Aust.), Vol. 1, No. 2, pp. 25—28. (19478): A Contemporary Eustatic Rise in Sea-level? Geogr. Journ., Vol. 109, p. 157. (1948) : Notes on the Geomorphology of the Pelsart Group of the Houtman’s Abrolhos Islands. Journ. Roy. Soc. West. Aust., Vol. 33 (for 1946-47), pp. 1-43. FAiRBRIDGE, R. W., and GIL1, E. D. (1947) : Study of Eustatic Changes of Sea-level. Austr. Journ. Sct., Vol. 10, pp. 63-67. FENNEMAN, N. M. (1902) : Development of the Profile of Equilibrium of the Subaqueous Shore Terrace. Journ. of Geol., Vol. 10, pp. 1-32. Francis—BoruFr, C. (1938): La probléme du plateau continental et des vallées sous-marines. Rev. Géogr. phys. et. Géol. dynam. (Paris), Vol. 11, No. 3, p. 254. Geixtie, A. (1903) : Text-book of Geology. London (Macmillan). 2 vols. (4th rev. ed.). Gitt, E. D. (1949) : Some Unusual Shore Platforms Near Gisborne, North Island, New Zealand (Roy. Soc. N.Z.) (In the press.) GREEN, A. H. (1882): Geology, Pt. 1., Physical Geology. London. GULLIVER, F. P. (1899) : Shore-line Topography. Proc. Amer. Acad. Arts & Shi, Vol. 34, pp- 149-268. JARDINE, F. (1925) : The Development and Significance of Benches in the Littoral of Eastern Australia. Repts. Gt. Barrier ” Reef. Comm., Vol. 1, pp. 111-130 (Tvans. Roy. Geogr. Soc. Aust., Old.). Jounson, D. W. (1919): Shove Processes and Shoreline Development. New MOE (Wiley), revised ed. 1938. Jounson, D. (1933) : Supposed Two-metre Eustatic Bench of the Pacific SHores: Congrés Int. Géogr., Cts. Rend., Paris, Vol. 2, pp. 158-163. JUK=s-BROWNE, A. J. (1884) : The Students’ Handbook of Physical Geology. London, 514 pp. — (1893): Geology. An Elementary Textbook. London. Jurtson, J. T. (1939: Shore Platforms Near Sydney, New South Wales. Journ. of Geomorph., Vol. 2, pp. 237-250. KAYSER, E. (1923) : ‘Lehrbuch der Geologie. Stuttgart (Enke), Vol. 1, 740 pp- (7th & 8th ed.). KUENEN, P. H. (1933) : Geology of Coral Reefs. The Snellius Expedition, Vol. V, Geological Results, pt. 2, 123 pp DE LAPPARENT, A (1906): Tvaité de Géologie. Paris (Masson), 5th ed. Lewis, R. G. (1937) : Studies in Earth Movements. Loughton, Essex. (Publ. by the author), 173 pp ; LYELL, C. Ce Elements of Geology. London (Murray), 6th ed. rev. MacrapyeEN, W. A. (1930: The Undercutting of Coral Reef Limestone on the Coasts of Some Islands in the Red Sea. Geogr. Journ., Vol.’ 75, pp. 27-34. DE MaRTONNE, E. (1934): Tvraité de Géographie Physique. Paris (A. Colin), 5th ed. (rev.), 3 vols. Murray, J. (1888) : On the Height of the Continents and the Depth of the Oceans. Scott. Geogr. Mag., Vol. 4, pp. 1-41. Nansen, F. (1905) : Oscillations of Shore-lines. Geogr. Jour n., Vol. 26, pp. 604-616. Novak, V. J. (1938) : On the Origin of the Continental Shelf. Vestnik Kral. Ceské Spolectnosti Nauk (Prague), for 1937 (No. 17), 27 pp. Park, J. (1925): A Textbook of Geology. London, 2nd ed., 527 pp. Ramsay, A. C. (1846): On the Denudation of South Wales and the Adjacent Countries of England. Mem. Geol. Surv. Gr. Brit., Vol. I, pp. 297-335. Reape, T. Merrarp (1877): President’s Address (1876). Proc. Liverpool Geol. Sec., Vol. 3, pt. 3, pp. 211-235. (1885) : Denudation of the Two Americas. Pyoc. Liverpool. Geol. Soc. (for 1884-5). (Pres. Add.) VON RICHTHOFEN, F. (1886): Fuihver fiir Forschungsreisende. Hannover. SHEPARD, F. P. (1937): Revised Classification of Marine Shorelines. Journ. of Geol., Vol. 45, pp. 602-624. TEICHERT, C. (1947) : Contributions to the Geology of Houtman’s Abrolhos, Western Australia. Proc. Lin. Soc., N.S.W., Vol. 71, pp. 145-196. ——— (1948): Late Quaternary Sea-level Changes at Rottnest Island, Western Austraha. Pyoc. Roy. Soc. Vic., vol. 59 (2), pp. 63-79. 307 Umperove, J. H. F. (1946): Origin of Continental Shelves. Bull. Amer. Assoc. Petr. Geol., Vol. 30, pp. 249-253. WeENtTWorTH, C. K. (1927) : Estimates of Marine and Fluvial Erosion in Hawaii. Journ. of Geol., Vol. XXXV, No. 2, pp. 117-133. WHITAKER, W. (1867) : On Subaerial Denudation, and on Cliffs and Escarpments of the Chalk and Lower Tertiary Beds. Geol. Mag., Vol. 4, pp. 447-454 and 483-493. von ZAHN, W. (1909): Die zerst6rende Arbeit des Meeres an Steilkiisten. J/itt. Geogr. Gesell. Hamburg, Vol. 24, pp. 193-284. SUMMARY OF DISCUSSION Dr. Shepard commented that steps across the continental shelf seemed from the study of a large number of charts to be practically the same in most parts of the world. As to storm-wave benches, tidal-wave investigations in Hawaii in 1946 had shown actual cuts 10 ft. or 20 ft. above normal sea-level. This was admittedly in soft material. But with repetition the same occurrence might take place in harder material. In general, said Professor Bartrum, there could be no doubt that surrounding platforms were uplifted. Professor Bartrum replied to criticism by Dr. Fairbridge of his own results by commenting on a series of slides, including many New Zealand examples, confirming the conclusions of Gulliver and Fenneman. He pointed out that Dr. Fairbridge showed inconsistencies with his later argument, in attempting to homologize platforms 2 ft. to 8 ft. above sea-level with those below. The examples of “ Old Hat’ structure were illustrated. Such phenomena were encountered only in certain con- ditions, where the rocks were impermeable, free from close-spaced joints, amenable to weathering, and in sheltered waters. A local example was ~ illustrated of a 96 ft. wide platform developed in Parnell Grit, having a gentle slope. The rocks were quite resistant when wet, but broke into pieces very readily on alternate wetting and drying. A series of other New Zealand examples was shown. Professor Cotton attempted to sum up the conflicting points made by Dr. Fairbridge and Professor Bartrum. Everywhere that erosion occurred, he stated, two platforms were tentatively developed—one towards the sea showed normal sloping profile, while the high-water platform of Bartrum was also present, making its way in towards the Jand. In certain rocks the top platform gets ahead in its development and we find the “ Old Hat ”’ type of erosion. In other cases the lower platform develops at the greater rate, and we find the normal shore-line profile. : COMMENTS BY J. A. BAaRTRUM, AUCKLAND UNIVERSITY COLLEGE Dr. Fairbridge’s observations of shore platforms in rocks other than limestones, which have abnormal solubility compared with most other rocks, appear to be limited. On New Zealand shores there are hosts of examples of wide, gently-sloping subaqueous platforms which have the profile demanded by Fenneman, Gulliver, and others of their school. He also minimizes the corrosive potentialities of waves as compared with subaerial processes, but any observer can readily satisfy himself that, in normal rocks, given suitable tools, waves are extremely capable corrosive agents. If, as Dr. Fairbridge maintains, the types of beach that I have termed the “Old Hat” and “ Storm-wave”’ shore-platforms, which differ at times as much as 10 ft. in height, are to be referred to one and the same 308 stand of sea-level, different processes must obviously have been involved in their formation. This does not seem consistent with Dr. Fairbridge’s scheme of shore erosion, but it is so with my own. ‘I may remark here that in New. Zealand there has been so much fairly recent block-faulting that correlation of any particular bench level with a particular phase of the Ice Age is peculiarly hazardous. I should like to deal next with platforms of the “ Old Hat” type. which occur solely in impermeable rocks free from open joints, readily amenable to weathering, and in very sheltered waters. Their surface lies a foot or so below high-water level and they are the product, as Dr. Fairbridge correctly states, of subaerial weathering. I personally regard this surface as a level of permanent saturation below which subaerial weathering cannot proceed. Dr. Fairbridge, on the contrary would carry subaerial weathering down to the level of low water at spring tide. This manifestly would be possible for permeable rocks or those affected by close-spaced open joints, but, if waves have any appreciable corrosive power, the platform so produced would be eroded yielding a “ normal ”’ off-shore platform. If Dr. Fairbridge’s views are correct and this plat- form is exposed at its present elevation merely by negative shift of sea- level, then its formation should be independent of the rock in which it is developed, provided that it was amenable to weathering. The nature of the joint fissures and the permeability of the rock should have no importance. The “Old Hat” type of bench, therefore, should not be infrequent: in actual fact it is by no means common. , “Storm-wave’’ platforms are developed only in fairly resistant rocks free from open joints at exposed locations such as headlands subject to attack by vigorous storm-waves and where reefs off-shore cause such waves to sweep upon the shore as surf (or waves of translation). Their surface is from a foot or two to as much as 8 ft. above high-water level, dependent on the vigour of the waves by which they are attacked, and, though initially rough in surface, in time may be smoothed down sub- aerially to the level of shallow pools of water lying on that surface. Reasons which have led me to regard these benches as the product of the sea at its present level are— (1) One can observe waves thundering on to these platforms during storms. (2) The benches never pass far from the end of a headland: towards a bayhead. (3) When they do so, they decline in level away from the headland. Occasionally the change to a lower platform is abrupt. In these cases observation shows that the waves responsible for carving the platforms have had their vigour reduced after passing the headland; at times this reduction is because. of deflection. It is clear that the platforms are unlikely to occur in open-jointed rocks, which would be disrupted freely at varied levels by pneumatic and hydraulic pressures. In conclusion, I would claim that Dr. Fairbridge has advanced no cogent reason for regarding platforms of the “‘ Old Hat” and “ Storm- wave’ type as developed during a period when sea-level was higher than now. . They therefore have no value in isostatic correlation of shore benches. | 309 hoe Al d SYMPOSIUM ON WAVE ANALYSIS AND WAVE PREDICTION : WAVES AND TSUNAMIS A SEISMIC SEA WAVE WARNING SYSTEM FOR THE PACIFIC By W. B. ZERBE, U.S. Coast and Geodetic Survey THE heavy loss of life and property in the Hawaiian Islands that accompanied the seismic sea wave of Ist April, 1946, brought to the attention of scientists and engineers the need for the development of a system for quickly detecting and reporting these waves so that the Hawaiian Islands and other areas might be warned in sufficient time to be spared a repetition of such a disaster. Although damaging waves have occurred in the past, progress in rapid communication and in instrumental development had not reached a point where a warning system was feasible. Soon after the earthquake of April, 1946, the Coast and Geodetic Survey undertook the develop- ment of the instruments and procedures required for the successful operation of such a system. These instruments, a visible recording seismograph with an alarm and a seismic sea wave detector, are now in operation, and sufficient progress has been made in the operation of the warning system to warrant reporting it to the scientific world. It was obviously desirable that the occurrence of a major earthquake should be known at once. The records from photographic recording seismographs, which are in general use, are not visible until they are removed and developed. Those that produce a visible record would have to be watched continuously, which is impracticable. A seismograph that would in some way signal an alarm was therefore indicated. This need has been met by an electronic recorder that not only produces a visible record, but also sounds an alarm. The alarm is sounded when the amplitude of vibration of the light-beam is large enough to cause the beam to strike photo-electric cells placed near the ends of its*swing. The alarm can be either audible or visual and it can be located in the station, the observer's quarters, or elsewhere. (This is a development of the electronic recorder described by F. Keller in the October, 1946, issue of Tvansactions of the American Geophysical Umon.) A recent development contains interesting added _ possibilities regarding the detection, location, and identification of submarine earthquakes. This involves the newly-discovered fact that these earthquakes sometimes generate low-frequency sound-waves peculiarly adapted for long-distance transmission through conducting layers of the sea-water. These waves pass into the ground structure of oceanic islands and can be recorded on special seismographs shortly after the higher-speed all-ground waves arrive. The complete warning system, as at present developed, consists of four Coast Survey seismograph stations, the reports from which will definitely fix the epicentre of the producing earthquake; a network of tide stations in the Pacific, some of which have seismic sea-wave detectors ; a seismic sea-wave travel-time chart; and a high priority communication system. 360 The centre of the system is the Coast and Geodetic Survey seismograph station at Honolulu. Here all seismograph reports will be received, epicentres determined, alerts issued, and wave reports evaluated. Here it will be determined whether or not an alarm is justified. Only a small number of the quakes that occur in the ocean produce seismic sea waves, and not all sea waves are large enough to be dangerous. All-must be treated with respect, however, by those involved in the system. Whenever the possibility of a sea wave exists, those charged with broadcasting warnings to the public and to military and other esta- blishments will be notified to “stand by’ so that no time will be lost in issuing a warning should it be found necessary. The sequence of events that would set the system in operation will differ at different times. Ideally an earthquake would be detected by the seismograph station as soon as it occurred and be reported to the central station where the position of the epicentre would be determined. If the central station is the first to detect the quake, reports will be requested from the other stations. If the epicentre is found to be under the Pacific Oean where it could generate a sea wave, selected tide stations, favourably situated to intercept the wave before it reached the Hawaiian Islands, would be alerted to watch their gauges for evidence of a wave and report their findings. From the seismic sea-wave travel-time chart the central station can determine quickly: what time to expect the wave in the Hawauan Islands, and consequently how much time can be used in obtaining tide station reports. Though other places than tide stations may at times be asked for reports, tide stations are in a more favourable position to report usable information, for waves -can be observed on the tide record that may otherwise go unnoticed. The fact that a wave is small at one place does not mean that it will not be large enough to be dangerous at another. To take care of the possibility that a quake might remain temporarily undetected and that the first hint of a seismic sea wave might be the arrival of the wave itself, the Coast and Geodetic Survey developed a seismic sea-wave detector. This is a simple device with no moving parts except a column of mercury which moves to close an electric circuit. It makes use of the change of air pressure in a vertical pipe brought about when the rise and fall of the sea has the twelve to twenty minute period -characteristic of a seismic sea wave. The detector screens out the rapid rise and fall of wind waves and the slow rise and fall of the tide, but automatically signals an alarm at a tide station upon the arrival of a seismic sea wave. Since most of the tide stations on Pacific islands are at military posts or communication centres where a twenty-four hour watch is maintained, an observer is always available to hear or see the signal. When the signal is observed the observer will check the tide record before alerting the Honolulu centre. Since the detector can be -actuated by the first part of the wave motion a few minutes before the arrival of the destructive part, it can also be used to sound an -alarm locally for the community or post in which it is located. (The instrument is described in greater detail in the January, 1948, issue of ‘the Coast and Geodetic Survey Journal.) Detectors have been installed at Honolulu, Hilo, and Midway, and another will soon be in operation at Palmyra Island. Others will be installed in the Aleutians. Places with large ranges of tide are being -avoided because the rate of rise and fall of the tide must not approach ‘too closely to that of a possible seismic sea wave. 361 The warning system‘is a co-operative undertaking. It binds into a network existing Coast and Geodetic Survey seismograph and tide sta- tions by using facilities of the U.S. Navy, Army, Air Force, and Civil Aeronautics Administration. These agencies, along with the Coast Guard, the Territorial Government, the City of Honolulu, and others, will broadcast warnings by radio, siren, airplane, and any other means necessary to clear the beaches and waterfront areas of threatened communities. Seismograph stations in the system are the Coast Survey stations at Tucson, Arizona; Sitka, Alaska; Fairbanks, Alaska; and Honolulu. To strengthen the system, the California University observatories at Pasadena and Berkeley will doubtless participate from time to time. Tide stations that can be used for wave detection include three in the Aleutians, one each at Midway, Johnston Island, Palmyra Island, Pago Pago, Kwajalein, Hilo, Honolulu, and others, including numerous stations on the mainland of North and South America. Although the warning system is not yet established in a complete form, it is in operation, and the quake of 8th September, 1948, in the region of the Tonga Islands provided a test of its efficacy. In this inst- ance perhaps more time was consumed in obtaining seismograph reports than was desirable, but the time available to the central stations was. sufficient to obtain reports from tide stations and others in the path of a possible wave. The travel-time chart showed that it would take a wave about 6 hours and 35 minutes to travel from the epicentre to Honolulu. As the time approached for the wave to arrive, planes took to the air in readiness to clear beach and waterfront areas, and all agencies were on the alert and ready to broadcast warnings. As the wave reports came in it became clear that though there probably was a wave, it was very small. The “ Stand by ” order was therefore rescinded and the “ All clear’ was. given. When the record was later removed from the Honolulu tide gauge, it showed that a seismic sea wave had arrived about on time. Its height was 6 in. So far as the public was concerned, the warning system operated. satisfactorily, but from the point of view of those at the centre the test indicated the desirability of some adjustments and additional studies. The basic plan, however, proved to be well designed to accomplish the task for which the system was created. WAVE ANALYSIS AND PREDICTION By G. E. R. Deacon, Admiralty Research Laboratory, England [A bstract| As soon as continous wave records were examined the fact that the observed wave profile is the resultant of a number of wave trains had to be recognized, and methods had to be developed to detect and measure each invisible wave-train to obtain the wave-spectrum. The examination of many such wave-spectra and the relevant wind charts shows that a wind blowing over the sea produces waves of all lengths up to a maximum that depends on the greatest wind strength. These component wave- trains travel independently across the ocean with the group velocities. appropriate to their periods ; the short waves generated at the beginning 362 of the storm are overtaken and outdistanced by the longer waves pro- duced when the wind is stronger, the separation between them increasing with distance (Barber and Ursell, 1948)("). The first indication at a distant recording station is a narrow band of long low swell; this is followed by shorter higher swell and the wave-band gradually broadens as the mean period decreases. The observed wave pattern at any place is generally a combination of waves generated by the local winds with swell components from remote sources. To predict the wave pattern or surf breaking on a coast from meteor- -ological charts and forecasts the effect of swell from each source must be taken into account and it is necessary to know how the wind energy is shared among the range of wave-lengths that are produced. Recent observations indicate that the amount of energy imparted to waves of a particular period depends on the difference between the geostrophic wind speed and the velocity of the wave and on the time during which the wind acts on the wave ; there is also a factor proportional to the wave period to allow for the increase with wave length of the capacity of a wave for absorbing energy without becoming unstable, and a factor inversely proportional to the wind speed to take account of evidence that there is an optimum wind speed for each wave-length, the growth of each of the shorter wave-lengths being decreased in turn as the rising wind strength -causes such values to be exceeded. Empirical methods based on such conclusions can be used with fair ‘success to predict the wave-spectrum from hour to hour on the west coast of the British Isles, but there are many outstanding problems. ot) “BARBER, INSEE, and URSELL, FE The Generation and Propagation of Ocean Waves and Swell. Phil. Trans. jn Soc., 240, 527 (1948). By Authority: R, E. Owen, ovement Spanien. Wollimeron! —1952. A: 5 ea ets AY