Cover Illustration: The ‘“A-Boat”’ It is doubtful that the many new, fairly luxurious, research vessels ever will obtain the affection and nostalgia reserved for the famed ATLANTIS. The ATLANTIS, designed and built for the Woods Hole Oceano- graphic Institution in 1931, sailed about one miltion miles in some 30 years during 270 cruises lasting from a few days to 6 or 7 months. On the average, the ship was at sea 250 days a year, working in the North and South Atlantic and adjacent gulfs and seas, the Pacific and Indian Oceans, and the Red Sea. Her two capable deep sea winches were used thousands of times to probe the ocean at all but the greatest depths. Statistics show only part of the story. The ATLANTIS probably made more hydrographic stations than any other ship. More important, she was the principal instrument in advancing the growth of modern knowledge of the ocean. Young men who became leaders in oceanog- raphy obtained their sea legs on her. Most of the modern equipment and techniques were tried out and developed on board the ATLANTIS. Her work in the Gulf Stream greatly advanced our knowledge of that vast current. ) Increasingly more accurate methods of echo sounding showed the roughness of the sea bottom and extended our knowledge of the Mid- Atlantic Ridge. The land-based method of seismic exploration was taken out to sea and revealed the thinness of the earth's crust beneath the ocean. Regardless of her small size, she did a tremendous amount of work. Her accommodations were none too luxurious; living and working con- ditions were arduous, particularly in the tropics, as she was not air- conditioned. Yet, the small number in her crew (19) and scientific party (8 or 9) made for a great camaraderie and created a stubbornness to ‘get the work done,’ regardless of difficulties. Boys, who came on board “through the hawse hole’ were taught navigation and seamanship and how to get along with the demands of science. Today, many of them are officers on the large new vessels. The ATLANTIS was a lucky ship. She went through many a fierce storm and several hurricanes with but minor damage. She never lost a man overboard nor was anyone seriously injured. Unfortunately, age and heavy sea duty began to tell. She was re- placed by the much larger, modern ATLANTIS //. On November 11, 1966, the “A-boat, ‘as she was known affectionately left Woods Hole to continue her career under the name EL AUSTRAL for the Hydro- graphic Office of the Argentine Navy. Many of those who saw her off were seen to wipe a tear from their eyes. Jan Hahn Editor, Oceanus ‘Nill MB NATIONAL OCEANOGRAPHIC DATA CENTER TTT MO GENERAL SERIES QUESTIONS ABOUT THE OCEANS PUBLICATION G-13 by HAROLD W. DUBACH and ROBERT W. TABER EDWIN J. SEREMETH Technical Adviser For Graphics Library of Congress Catalog Card Number: 67-60068 Published by the U.S. Naval Oceanographic Office Washington D.C. 20390 For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, D.C. 20402 - Price 55 cents (paper cover) The National Oceanographic Data Center is sponsored by U. S. Government agencies having an interest in the marine environment; it is governed by an Advisory Board composed of representatives of these activities and the National Academy of Sciences. The U. S. Naval Oceanographic Office is assigned responsibility for management of the National Oceanographic Data Center. The Sponsoring Agencies are: Atomic Energy Commission Bureau of Commercial Fisheries Coast and Geodetic Survey Coast Guard Coastal Engineering Research Center Department of the Navy Geological Survey Health, Education and Welfare National Science Foundation Weather Bureau ACKNOWLEDGMENTS The authors acknowledge with thanks the historical brief on the famous Woods Hole Oceanographic Institution vessel ATLANTIS sup- plied by Mr. Jan Hahn. The authors wish to give special recognition to the science class of Zundelowitz Jr. High School, Wichita Falls, Texas, which was a principal catalyst responsible for the creation of this book. We gratefully acknowledge the assistance of Mrs. L. Annette Farrall, Mrs. Wilhelmenia Bowe, and Mr. William Lyons. PUBLICATIONS IN THE NODC GENERAL SERIES: G-1. G-2. Introduction to the National Oceanographic Data Center Oceanographic Vessels of the World, Vol. |, Vol. II, and Vol. Ill EQUALANT |I—Data Report, Vols. | & Il A Summary of Temperature-Salinity Characteristics of the Persian Gulf EQUALANT II—Data Report Atlas of Bathythermograph Data—Indian Ocean EQUALANT III—Data Report Guinean Trawling Survey—Data Report (In press) Water Masses and Density Stratification, Vol. I— Western North Atlantic Ocean Selected IIOE Track Charts The Variability of Water Masses in the Indian Ocean Indian Ocean Atlas—Interpolated Values of Depth, Salinity, and Temperature on Selected Sigma-t Surfaces 100 Frequently Asked Questions About the Oceans Summary of NODC Ad Hoc Committee and Working Group Activities Topical Readings in Oceanography (In work) Junior High School Students Ask Questions About the Ocean at the 17th International Science Fair in Dallas, Texas. THE OCEAN Boats float in it. Fish swim in it. Stones sink in it. They all get wet. from HELLO AND GOOD-BY, Copyright, (C), 1959, by Mary Ann and Norman Hoberman, reproduced with the permission of the publishers, Little, Brown and Company: Boston. vi No. OoRWN = CONTENTS Question . What is the greatest depth of the ocean and where is it?. . . PM AS thevOGeal Oller ot we ee CH Te 0D Pee Where dolwaves COME NOMlre wie: ot sociale ava. aes woh . What is the rate of sediment deposition on the sea floor?. . . How thick is the ice in the Arctic Ocean? ............ . If all the ice in the world should melt, what would PALE) Woda tc fname usarncpnnes Saleh eS ees ee, ek thee ehh MiVinaticauses theved tide? 7). GRoL wan Wad cae. PMN atTiakes TMBsOCRAM Sal EY? ans ao scveevis avis) c- dun oan ehnoatal alle . ls there gold or other precious elements in the ocean? If How long (and big) is the Gulf Stream? ............. What is a waterspout and what causes it? ............ What commercial products other than fish are obtained EMAL SCO Hicis ucc'he thie ate nehcor aarp eee eat ole athe, (aOR Ts Mate weg What is the annual fish take by the United States? ...... How does the fish take of the United States compare with ERPS COUMUTIES hain rt Ces quia lar ak ep Ldn oa Nha) Shalt he . What are the primary pollutants found in the sea and what ANOMUME IT SOUINGES A ancl. seal coe th stn esate Ronee RS Bee Oi SR RN Viatal vA tlantiS2s peice ee tile 2 y.08) ree Le Sue ets Oot ee . What does the sea floor look like? ................ Are there strong currents at depths beneath the ocean surface that might compare to the “jet stream’ in the upper levels of the atmosphere? .................. Why dGes athe SeaahOaIM ae swces ped acesleeos (hoot eset he eee How did seas, such as the Black, Red, and White, get their RS CRAe PS Oh tie) SRR SE EE PO Eh SGA E ey RS IS A . What causes hurricanes and how do they differ from How:high: isthe highest, wave?its wis del a SUIS A . How many species of fishes are there? .............. . Beside the whale, what other mammals live in the oceans? vil No. Sie 32: So: 34. 35. 36. SH) 38. 218), 40. 41. 42. 43. AA. 45. 46. 47. 48. 49. 50. 51. 52. 53. 54. 55. 56. 57. 58. 59. 60. 61. 62. Question What: causes the tides? <0 5.5 2.5) eerie tas Meese ease Why do tide ranges in the same geographical areas of the world differ:so greatly? as... iin eke ais as ale) aate) eee ee How deep in the ocean can one see with natural sunlight? . What is the volume of the world’s oceans?............ Do any creatures in the sea other than the porpoise talk?. . How do oysters produce pearls? ...............45- How far into the ocean can one ‘see’ the effect of a FIVOR 2 spiel oie Was ey ae eel ea en Re ee ls seaweed a weed? What is it and how does it grow? .... What is green'scum?. «=. asus. os casi 2 ee What are algae?! sis Sateen Se eee Se ee Can gold, silver, platinum, or diamonds be mined from the sea?’ ..sac83,-a wa eelss is a ee Has a sea gull, albatross, or other sea bird ever flown across the Ocean? «35% osm. kone okie Ee eee eee Are there volcanoes under the sea like those on land? .... Can ‘tidal “waves be forecast?4. 2. oo. aan eee What is the ‘bends’ and how do divers become afflicted What is ‘‘fish farming’ and where is it practiced? ....... How far has a message in a bottle ever traveled on the OCEAN? inate ehaete oe. i ee aes ao eee eit ee How are oceanographic observations taken beside from a SIU? eco aa le ea Ee Se ees SG ee eae viii Page Question PAV MALISIOIOIUMIIMESCEMCEN: woatelcaice te sls liacslc Wileteflets! o-clens ma Whratrisitnecontinentalrshelifi?@ 1. eisai cs eaieks Griieoe essa . Has an efficient method of obtaining fresh water from the SPAIDPENINVENICEC ear ute ce id: ei cece MeUNiRN ete er tee a ee . Why is the Cape Hatteras area known as the graveyard . Does oceanography include the study of lakes and streams? PA ices: DIGMIEOME) hone epee ist ere alee Mea BUN nee Are there really sea monsters?.). os 8 ee ee ae Vial TEV GP eR ot ae cea ND A Re Sa ee Sena eee San ene neg Saal How do submarines navigate when submerged for weeks at ARENINT ELC Ne fe Seater oa tae ee rene he eve Caen eae ah AP aa Meee wat ats How fast can a porpoise swim? Is it the fastest swimming THIS ct US ee a aeaca PRN ae A aR i ed What is the most important discovery made about the CYCLE STAM Ralarsthard hue Mle tees ena i Oe aE ae Weta es MUTASE MOOS tare eee Silt Wie secs ee ins SM tt ee Aut . How much do scientists really know about the oceans? .. . Pan atianeviceslanas? 4.2%. s-.Sehs.. Ve ee Pe ee Panatus the My arOlogic CVGlE? <3 . in the northern subtropical region. The Pacific is less salty than the Atlantic because it is affected less by dry winds and resulting high evaporation rates. In the deeper waters of the Pacific, the salinity ranges from 34.6 “/oo to 34.7 “/oo. The Arctic and Antarctic waters are the least salty. Some areas in the world have abnormally high salinities; for example, the Red Sea and Persian Gulf have salinities exceeding 42 “/oo. The “hot, salty hole” in the Red Sea has salinities exceeding 270 “/oo (close to saturation) at depths below 2,000 meters. Very low salinities occur where large quantities of fresh water are supplied by rivers or melting ice. Salinity in the Baltic is 2 “loo-1 Hoowand in the Black Sea about 18 “/oo. Deacon, G. E. R (Ed.) Seas, Maps, and Men, Doubleday and Company, 1962. King, Cuchlaine A. M. Oceanography for Geographers, Edward Arnold Ltd. (London), 1962. Dubach, Harold W. A Summary of Temperature-Salinity Characteristics in the Persian Gulf, Publication G-4, National Oceanographic Data Center, 1964. 50 46. Has a sea gull, albatross, or other sea bird ever flown across the ocean? Some sea birds live along the coast and rarely travel far from shore. Others spend their lives over the ocean returning to land only to nest. Sea gulls are coastal birds, so they would not normally cross the ocean. However, many oceanic birds banded in Europe have been recovered in North America. Kittiwakes banded by scien- tists in the Barents Sea area have been recovered in New- foundland 4 months after banding. Puffins, fulmars, and petrels also are Known to have crossed the Atlantic from Eu- rope to North America, and the Arctic skua and the At- lantic cormorant fly from Northern Europe to the Afri- can coasts. By far the most impressive travelers are the Arctic tern and the albatross. The Arctic tern, which is the size of a small sea gull, regularly mi- grates from its breeding grounds in the Arctic to the Antarctic. It molts in the Antarctic and returns to the Arctic to nest each year. The albatross is also an oceanic bird, returning to land only . to nest. Banding records indicate that albatrosses fly around the world, especially during their first few years of life. Belopolskii, L. O. Ecology of Sea Colony Birds of the Barents Sea, 1957. (Translation), Israel Program for Scientific Translations, 1961. Salomonsen, Finn The Food Production in the Sea and the Annual Cycle of Faeroese Marine Birds, Oikos 6 (1): 92-100, 1955. Solyanik, G. A. “Discovery of a Banded Polar Sterna Paradisae Brunn in the Antarc- tic,” Soviet Antarctic Expedition 2:28-37 (translation), 1959. Vaucher, Charles : Sea Birds, Dufour Editions, 1963. 51 47. Are there volcanoes under the sea like those on land? Volcanoes have built up impressive mounds and ridges under the oceans. In many places these volcanic ridges extend above the sea sur- face as islands. Iceland is part of a ridge of volcanoes that also includes the Azores. The Hawaiian Islands are part of a volcanic chain that ex- tends across the Pacific for nearly 2,000 miles. f On November 14, 1963, a new volcanic island began to rise from the 7 North Atlantic, just south of Iceland. Fishermen witnessed the birth of . the island, now known as Surtsey. Before the volcanic activity began, the ocean at this spot was 425 feet deep. After the initial eruption, an t outpouring of lava built up about an acre a day. One of the first scien- tists to arrive on the scene was Professor Paul Bauer of American Uni- versity, who continuously observed and recorded the growth of Surtsey. His pictorial and scientific documentation of this evolutionary process as a day-by-day event is the first and only such record and should be a most useful record for research study by geologists for years to come. A 30-minute film is available on Surtsey. Blanchard, Duncan C. From Raindrops to Volcanoes, Doubleday and Company, 1967. Gaskell, T. F. World Beneath the Oceans, American Museum of Natural History, 1964. Thorarinsson, Sigurdur “Surtsey—Island of Fire,’ National Geographic, Vol. 127, No. 5, May, 1965. 52 48. Is life found at all depths in the ocean? This question was settled for all time in 1960 when Piccard and Walsh reported a flatfish, resembling a sole, at a depth of 35,800 feet. From the porthole of the bathyscaph TRIESTE they observed a fish about 1 foot long and 6 inches wide swimming away. As recently as 1860, some scientists believed that marine life could not exist below 1,800 feet. This view was discredited when a telegraph cable brought up from a depth of 6,000 feet was found to be covered with a variety of marine life. HATCHET FISH ACTUAL SIZE VIPER FISH ) Y% size In 1872 scientists aboard the HMS CHALLENGER found life in the deepest areas which they were able to trawl, but it was not until steam trawls and wire rope became available that trawl collections could be ob- tained from the deepest trenches. 53 293-387 O-68—5 In 1951, the Danish oceanographic ship GALATHEA dredged various invertebrates from a depth of 33,433 feet in the Philippine Trench and a year later caught fish at a depth of 23,400 feet. Deacon, G. E. R. (Ed.) Seas, Maps, and Men, Doubleday and Company, 1962. Piccard, Jacques, and Robert S. Dietz Seven Miles Down, G. P. Putnam’s Sons, 1961. Soule, Gardner The Ocean Adventure, Appleton-Century, 1966. 54 49. What causes “‘tidal waves’’? “Tidal waves” are not caused by the tides, but by movement of the ocean floor. Their proper name is tsunami, a word of Japanese origin. They are also commonly called seismic sea waves. Submarine earthquakes, landslides, or volcanic eruptions create tsu- namis; a submarine disturbance may produce three or four waves with a wave length (crest to crest) greater than 3 miles, although their height over the open ocean may be only 1 foot. Speed of advance can exceed 500 miles an hour. As the waves approach shore, they are slowed and the water behind piles up to tremendously destructive heights. Cowan, Robert C. Frontiers of the Sea, Doubleday and Company, 1960. Gaskell, T. F. World Beneath the Oceans, American Museum of Natural History, 1964. Stewart, Harris B., Jr. Deep Challenge, Van Nostrand, 1966. 55 we? wauts 2° e ey " Sete OA OTT lit 4 VERTICAL DISPLACEMENT SUBMARINE LONG — PERIOD RESONANCE Or AVALANCHES EARTHQUAKE WAVES OF SUBMARINE FLOOR TRENCH WATER 50. Can “‘tidal’’ waves be forecast? Yes, ‘‘tidal’’ waves (tsunamis) can be forecast, because the earth- quake waves causing them cross the ocean in only a few minutes and can be picked up by seismograph stations hours before the sea wave arrives. After the destructive tsunami that struck the Hawaiian Islands in 1946, killing 173 people and destroying 25 million dollars worth of property, a warning system was set up in the Pacific. Seismograph sta- tions provide information on the time and location of the quake. If the epicenter of the quake is under the sea, a tsunami may result. Whena quake is noted, tide stations are alerted to watch for indications of a wave. A travel time chart centered on the Hawaiian Islands is used to esti- mate time of arrival of the waves. Warnings of estimated time of arrival are transmitted through an international Pacific-wide communication system. The U. S. Coast and Geodetic Survey operates the warning service, which has its headquarters in Honolulu, Hawaii. Bowditch, Nathaniel American Practical Navigator, U. S. Naval Oceanographic Office, 1958. , Gaskell, T. F. World Beneath the Oceans, American Museum of Natural History, 1964. U.S. Coast and Geodetic Survey Tsunami, The Story of the Seismic Sea-Wave Warning System, 1965. 58 51. What is the “bends” and how do divers become afflicted with it? High pressure at depth causes some of the nitrogen in a diver’s body tissue to dissolve in his blood. If he ascends too rapidly, bubbles will form in the blood and collect in his joints and bone marrow, causing the extremely painful condition known as the “bends.” It is not ordinarily fatal unless bubbles collect in the spinal cord or brain, but the pain will continue for several days unless the diver is put under pres- sure and decompressed gradually; if the condition goes untreated there will be bone damage. After a long dive, a diver is returned to normal pressure gradually so that nitrogen in the blood may be released through the lungs, avoiding the ‘‘bends.”’ Bond, George F. “Medical Factors in Diving Safety,’’ Signal, October, 1965. Gaskell, T. F. World Beneath the Oceans, American Museum of Natural History, 1964. Rebikoff, Dimitri Free Diving, E. P. Dutton and Company, 1956. 59 52. Are all fishes edible? Not all fishes are edible. Some have organs that are always poisonous to man; others sometimes become toxic because of certain elements in their diet. In Japan, a national dish called fugu is highly prized. It is pre- pared from the puffer fish, and the gonads of the puffer are highly poisonous. For this reason, fugu is only served in restaurants licensed by the government. Consumption of sharks and rays has been known to cause illness or death; this was probably because the victim ate a portion of the liver, which contains a very high concentration of vitamin A that the human body cannot tolerate. There are 300 tropical species of fishes that cause fish poisoning; one type of poisoning is commonly known as ciguatera. A particular species may cause ciguatera when caught on one side of an island, but not if caught on the other side. These tropical fish are associated with reefs and do not usually venture far from the home reef; for this reason, the people living on one island may eat a certain species of fish, while those on a nearby island would not. No one knows what causes the fish to be- come poisonous, but most investigators agree that it isssomething in the diet. There is no method to determine before a fish is consumed whether or not it will cause ciguatera. Some common species of fish known to cause ciguatera are: surgeon fish, jacks, porgies, snappers, goatfish, moray eels, wrasses, and barracudas. Scombrid fish, commonly known as tuna or mackerel, have been known to cause scombrid poisoning, usually because of inadequate preservation. The flesh of scombrid fish contains bacteria which, if the fish is not preserved soon after capture, begin to produce a histamine- like compound. This compound, if ingested by humans, causes a severe allergylike reaction and may even lead to death. Fish, C. J. and M. C. Cobb. Noxious Marine Animals of the Central and Western Pacific Ocean, U.S. Dept. Interior, FWS, Res. Rept. 36, pp. 1-45. Norman, J. R. . A History of Fishes, Hill and Wang, 1963. Randall, John E. “A Review of Ciguatera, Tropical Fish Poisoning with a Tentative Explanation of Its Cause,’’ Bull. Mar. Sci. Gulf and Caribbean 8(3), pp. 236-267. 60 53. What other sea life is used for human consumption? Fish are only one form of marine life used for food. Two other im- portant sources are shellfish and algae. Shellfish are not fish at all; rather, they are members of two large groups of marine animals—crustaceans and mollusks. Lobsters, crabs, and shrimp are the most popular crusta- ceans on American tables. Spiny lobsters, Alaskan king crabs, and prawns are also harvested for food. Clams, oysters, and scallops are the most commonly eaten mollusks in this country. However, many other mollusks are used in some parts of this country and in other parts of the world. Mussels and cockles are popular in Europe, and squid is popular in Southern Europe and the Orient. Abalone is eaten in the Orient and the Western United States. One noted delicacy of the West Indies is conch salad; conchs are also used in chowder. Still more exotic delica- cies are sea urchins and sea cucumbers; these animals are relatives of starfish. Although not popular in this country, sea mammals provide food for many peoples. Whales provide a great deal of meat which is marketed commercially in Japan and the Scandinavian countries. The Eskimo has depended on seals and walruses for food, oil, fur, and leather for centuries. Food from the sea is not limited to animal life. Seaweeds have also been used as food for centuries. In Iceland, so/, a red alga, is used as a vegetable during the long winters. Other algae have been boiled and made into puddings. Seaweed is also eaten in the British Isles. The use of seaweed for food is most highly developed in Japan. Nori, a red alga, is cultivated as a crop on nets or bushes set in quiet bays. In the past, Hawaiians have made use of a wide variety of seaweeds, and the most select varieties were grown in special ponds for the nobility. Kelp, a brown alga, is the raw material for a gelatin used in many food products. The growing world population, coupled with the shortage of protein foods in underdeveloped areas, has stimulated interest in algae as a source of cheap protein. Flour enriched with protein extracts from algae has been used in baked goods. Dawson, E. Yale Marine Botany, New York, Holt, Rinehart and Winston, 1966. Hallsson, S. V. “The Uses of Seaweeds in Iceland.’’ Proceedings of the Fourth Inter- national Seaweed Symposium, pp. 398-405, 1964. 61 293-387 0-686 Hundley, J. M., R. B. Ing, and R. W. Krauss “‘Algae as Sources of Lysine and Threonine in Supplementing Wheat and Bread Diets,’’ Science 124 (3221): 536-537, 1956. Storer, Tracy |. and Robert L. Usinger General Zoology, McGraw-Hill Book Company, 1957. 62 54. What is fish protein and why is it important? Fish protein is a substance containing all the amino acids essential to humans in proper proportions to maintain health. In concentrated form, fully dehydrated and defatted, it can be shipped and stored for long periods without refrigeration. Protein deficiencies exist in areas of the world where starchy foods are used as a dietary staple. The critical areas of the world are the Far East, Near East, Africa, and Latin America. In these areas, nearly 60 percent of the people receive less than one-half ounce of animal protein daily. It has been stated many times that two-thirds of the world’s population lack sufficient animal protein. Roughly refined fish protein has been used as feed for chickens, pigs, and cattle, but it was not until February 1, 1967, that the U. S. Federal Food and Drug Administration approved the use of whole fish protein concentrate for human consumption. The U. S. Congress has authorized a pilot plant in the Pacific North- west, and plans have been made to set up demonstration plants in coun- tries whose people have protein deficiencies. The purpose of the program is not to ship fish protein to other countries, but to help them develop their own industry. Varieties of fish that are not presently used for food can be used for protein concentrate to supplement the diet of millions of people who are not receiving enough protein to maintain a healthy existence. Food and Agriculture Organization (UNESCO) The Director-General’s Program of Work and Budget for 1966-67, C. 65/3, April 1965. U. S. Department of the Interior, Bureau of Commercial Fisheries Fish Protein Concentrate, Reports 1-5, 1962. Van Camp Sea Food Company Potential Resources of the Ocean, Long Beach, California, 1965. 63 55. What is “fish farming’ and where is it practiced? For the most part, man’s role is still that of a hunter rather than a farmer of the sea. In the future, however, it is probable that food shortages will require regulation of the life cycles of marine animals and plants in much the same way as on land. This might include altering the bottom environment, hatching of fish eggs, fencing breeding areas, fertilizing plants, and use of drugs to control diseases. Japan has developed fish farming and aquaculture to a higher degree than any other country. Fish-farming centers have been established in the Inland Sea to offset the decrease in catch of high quality fish in coastal waters. Eggs are hatched and fries released into the waters of the Inland Sea. By growing oysters on ropes hanging from rafts, the Japanese have increased the yield per acre to 50 times that of conventional methods. Oyster culture is also highly developed in the Mediterranean Sea where oysters are harvested from sticks thrust into the shoal bottom. Off the coast of California old streetcars and automobiles have been dumped into the ocean to form artificial reefs to attract fish. Possible methods of fencing sea areas include the use of nets, elec- trical impulses, and ultrasonics. Fertilizers have been used experimentally in enclosed areas of the sea, but they have stimulated growth of weeds and unwanted species as well as of desirable fish. Clarke, Arthur C. The Challenge of the Sea, Holt, Rinehart and Winston, 1960. Deacon, G. E. R. (Ed.) Seas, Maps, and Men, Doubleday and Company, 1962. Hull, Seabrook The Bountiful Sea, Prentice-Hall, 1964. 64 56. How far has a message in a bottle ever traveled on the ocean? Each year, the Woods Hole Oceanographic Institution releases be- tween 10,000 and 20,000 drift bottles off the East Coast of the United States to obtain information on currents in the ocean, particularly over the continental shelf. Clear 8-ounce carbonated-drink bottles are com- monly used. Dry sand is added for ballast and a self-addressed postcard is included, requesting the finder to note the date and location of finding. Bottles are released from ships, ferry boats, offshore towers, aircraft, and even blimps. The rate of return has been 10 to 11 percent. Records of all bottles released and recovered are kept in an IBM punchcard system. ne ee SC) — a) = —_/ LA faa ACU, ae a a _——_ / — V4 SLATTED eae Woods Hole has records of a number of bottles that have crossed the Atlantic from the United States to Ireland, England, and France—a dis- tance of 3,000 miles. Other drift bottles have made a nearly complete circuit, passing the Azores and coming ashore in the West Indies after having drifted 5,000 or 6,000 miles. Probably the longest undisputed drift on record was a bottle released June 20, 1962, at Perth, Australia, and recovered almost 5 years later near Miami, Florida. Oceanographers at the Tropical Atlantic Biological Laboratory estimated that the bottle had traveled some 16,000 statute miles at a speed of about 0.4 mile per hour. The most probable route was around the Cape of Good Hope, north along the Coast of Africa, across the Atlantic to northern Brazil, north along the South American Coast into the Gulf of Mexico, and through the Florida Straits to Miami. 65 Lateral! 57. What is the difference between hydrography and ocean- ography? To explain the difference between hydrography and oceanography, the ocean can be compared to a bucket of water; then hydrography is the study of the bucket and oceanography is the study of the water. Hydrographers are primarily concerned with the problems of naviga- tion. They chart coast lines and bottom topography. A hydrographic survey usually includes measurement of magnetic declination and dip, tides, currents, and meteorological elements. Oceanography is concerned with the application of all physical and natural sciences to the sea. It includes the disciplines of physics, chem- istry, geography, geology, biology, and meteorology. Physical oceanography is primarily concerned with energy transmis- sion through ocean water, specifically with such items as wave forma- tion and propagation, currents, tides, energy exchange between ocean and atmosphere, and penetration of light and sound. Chemical oceanography is a study of the chemical properties of sea water, of the cause and effect of variation of these properties with time and from place to place, and of the means of measuring these proper- ties. Biological oceanography is the study of the interrelationship of marine life with its oceanic environment. The study includes the dis- tribution, life cycles, and population fluctuations of marine organisms. Geological oceanography deals with the floor and shore of the oceans and embraces such subjects as submarine topography, geological struc- ture, erosion, and sedimentation. The interrelationship of specialties is one of the main characteristics of oceanography. Oceanographic and hydrographic surveying may be combined on the same ship. Many times the words ‘‘oceanography”’ and “‘hydrography’’ are used interchangeably. Bowditch, Nathaniel American Practical Navigator, U. S. Naval Oceanographic Office, 1958. 67 58. How old is the science of oceanography? Mankind has been interested in the oceans since before the time of Aristotle, who wrote a treatise on marine biology in the fourth century B.C. The early studies of the ocean were concerned with problems of commerce; information about tides, currents, and distances between ports was needed. While he was Postmaster General, Benjamin Franklin prepared temperature tables by means of which navigators could determine whether or not they were in the Gulf Stream. This resulted in faster mail service to Europe. The beginning of modern oceanography is usually considered to be December 30, 1872, when HMS CHALLENGER made her first oceanographic station on a 3-year round-the-world cruise. This was the {HMS. CHALLENGE 1872-1876 — first purely deep-sea oceanographic expedition ever attempted. Analysis of sea water samples collected on this expedition proved for the first time that the various constituents of salts in sea water are virtually in the same proportion everywhere (Dittmar’s principle). 68 Even before the CHALLENGER expedition, Lt. Matthew Fontaine Maury of the U. S. Navy was analyzing log books of sailing vessels to determine the most favorable routes. He did much to stimulate inter- national cooperation in oceanography and marine meteorology. The present U. S. Naval Oceanographic Office is an outgrowth of his efforts. Dougherty, Charles M. Searchers of the Sea, Viking Press, 1961. Guberlet, M. L. Explorers of the Sea; Famous Oceanographic Expeditions, Ronald Press, 1964. Hull, Seabrook The Bountiful Sea, Prentice-Hall, 1954. 69 59. What universities and colleges have oceanographic courses? Before World War I1, only two universities in the United States granted degrees in oceanography. By 1966, at least 50 colleges and uni- versities were granting degrees in oceanography, marine biology, and ocean engineering; at least 20 others offered courses. Because oceanographic facilities and ships are expensive, most institu- tions offer a broad training program covering the basic sciences, mathe- matical sciences, and some introductory environmental courses. Nor- mally, the oceanographic curriculum is available to those who have completed the bachelor’s degree. Specialization in marine biology and marine geology is available to undergraduates at some schools. In June 1966, the Sea Grant College Act, first suggested by Dean Athelstan Spilhaus, now President of the Franklin Institute in Philadelphia, and introduced into Congress by Senator Claiborne Pell (Rhode Island), was passed. This project to develop and support universities in much the same fashion as land grant colleges is being administered by the National Science Foundation. ye. ze eee ap oi ee eh Saag Kg Scripps Insrirurion of OCEANOGRAPHY La Jolla, California A student interested in becoming an oceanographer should first major in one (or more) of the basic sciences—physics, biology, geology, chem- istry, or meteorology. His later study of the ocean will relate to his past major. Most institutions offering degrees in oceanography require a bachelor’s degree as a prerequisite. Oceanographers are expected to have mathematics through calculus. 70 Individuals planning to become oceanographers should begin prepara- tion in high school; courses should include the sciences, mathematics, and a foreign language if possible. The best training for oceanography is to get into the ‘‘toughest’’ undergraduate science curriculum possible and to work hard. Single copies of a list of colleges and universities offering degrees in oceanography may be obtained without cost from the National Ocean- ography Association, Suite 301, 1900 L Street, N. W., Washington, D. C. 20036. Interagency Committee on Oceanography University Curricula in Oceanography, \CO Pamphlet No. 23, Washington, D. C., 1966. National Oceanography Association Oceanography Curricula, Washington, D. C., 1967. Oceanology International Yearbook, 1968, ‘‘Academic and Research Programs in Oceanology,” Industrial Research Publications, Beverly Shores, Indiana, June 15, 1967. 71 60. Who hires oceanographers? Between 2,500 and 3,000 scientists and technicians are employed in oceanography and related fields of marine science in the United States, and the number is growing. Most of these scientists are employed by colleges and universities and by university-operated oceanographic laboratories, where they are usually engaged primarily in research. The Federal Government employs a substantial number of ocean- ographers. Many oceanographic positions are in activities of the Navy; the Naval Oceanographic Office in the Washington, D. C., area probably employs more than any other single activity. Government agencies with sizable oceanographic staffs are ESSA (Environmental Science Services Administration), with laboratories located in Miami and Seattle; BCF (Bureau of Commercial Fisheries) with laboratories at 14 coastal loca- tions; and Public Health Service, with three shoreside research stations. The Bureau of Mines marine work is at Tiburon Island, California. Marine scientists employed by the U. S. Coast Guard and the CERC (Army Engineers) are usually based in Washington, D.C. A total of 22 Government agencies conduct oceanographic work of some kind. States bordering the ocean and Gulf of Mexico also employ quite a number of marine specialists. Oceanographers are employed in limited but growing numbers by private industry (manufacturers and consulting firms), independent non- profit laboratories, fishery laboratories, and local Governments. Board of U.S. Civil Service Examiners Your Future in Oceanography in Establishments of the U. S. Government, Announcement No. 371B, September 28, 1965. Gaber, Norman H. Your Future in Oceanography, Richards Rosen Press, 1967. Smithsonian Institution Opportunities in Oceanography, Publication No. 4537, 1964. 72 61. What is the largest oceanographic research ship? The Japanese Arctic Research Ship FUJ// is the largest ship built for oceanographic research, although larger ships have been converted from other uses. FUJ/, which was launched in March 1965 has a displace- ment of 8,305 tons (full load). She was designed for breaking ice more than 20 feet thick, and her bow is heavily armored for driving the ship on top of the ice field and crushing it by sheer weight. i a Ps sool fm From 1957 until 1965 (when FUJ/ was launched) the Russian Oceanographic Research Ship M/KHA/L LOMONOSOV was the largest ship designed for oceanographic work. That ship has 16 scientific laboratories capable of performing any type of investigation or analysis. The scientific staff of 69 includes women scientists. Displacement is 5,960 tons. The largest U. S. oceanographic ships are DISCOVERER and OCEANOGRAPHER with a length of 303 feet and displacement of 3,805 tons. Capurro, Luis R. A., Albert M. Bargeski, and William H. Myers Oceanographic Vessels of the World, \GY World Data Center A for Oceanography and the National Oceanographic Data Center, 1961. 13 62. How are oceanographic observations taken beside from a ship? Because oceanographic ships are expensive to operate, difficult to anchor in deep water, and limited in speed, continuous observations in one location and surface observations over wide ocean areas can best be accomplished by means other than ships. Buoys have been used for many years to obtain measurements of surface and subsurface currents and temperatures, as well as to observe meteorological conditions. These observations were mostly made near shore because of the difficulties in deep-sea anchoring and long-distance radio transmission. More recently other measurements have been in- cluded, such as of salinity and waves. There is increasing interest in setting up networks of moored buoys which would transmit oceanographic and meteorological information by radio or satellite relay. The NOMAD (Navy Oceanographic Meteorological Automatic Device) buoys have withstood hurricanes and therefore supplied timely and useful data which could not have been collected by ships. FLIP (Floating Instrument Package) is a hybrid ship-buoy. It is towed in the horizontal position to its location, where ballast tanks at one end are flooded, thus flipping it to the vertical position. FLIP 74 eee serves as a stable, manned platform or ‘buoy’ with observation ports extending to a depth of about 300 feet. Offshore towers have also been used for collection of oceanographic data. Some, such as the Navy Electronics Laboratory tower located a mile off the San Diego, California, coast, have been built specifically for oceanographic research; others, such as the Air Force radar towers (Texas towers), were built for other purposes but also used as observation sites by oceanographers. The Coast Guard is undertaking a significant and ex- tensive oceanographic data collection program on its new offshore towers. These towers, which replace the lightships as outer channel markers to major East Coast and West Coast ports, are being equipped with an impressive array of oceanographic instruments. Surface data, primarily temperature, have been collected by ex- tremely sensitive sensors on aircraft and satellites. Frequent flights have made it possible to map the meanderings of the Gulf Stream. Subsurface observations have been made by submersibles and by divers operating either from the surface or from underwater laboratories. Cromie, William J. Exploring the Secrets of the Sea, Prentice-Hall, 1962. Yasso, Warren E. Oceanography, A Study of Inner Space, Holt, Rinehart and Winston, 1965. 76 63. What is bioluminescence? Bioluminescence is light produced by living organisms, both animals and plants. In contrast to incandescent light, high temperatures are not necessary; oxygen, however, appears to be essential to the light- producing process. Thousands of species of marine animals produce bioluminescence; most of them are animals of the lower orders. In addition to single- celled animals, various jellyfish and related animals produce displays. Among vertebrates, luminescence is found only in certain fishes and sharks. Displays are seen most commonly in warm surface waters. Although most of the organisms are small, there are such immense numbers present that brilliant displays occur when the waters are disturbed by the passage of a ship at night. Luminescent bacteria are present in sea water, but not in fresh water, and can cause decaying fish to glow in the dark. At ocean depths where light does not penetrate, there are strange- looking luminescent fishes. Beebe estimated that 96 percent of all the creatures brought up by nets were luminescent. There is controversy among biologists concerning the purpose of lights on marine animals. Some creatures have well-developed eyes but no light to enable them to see in the dark; others have brilliant light organs but are too blind to see. The property of luminescence is perhaps used as a defense against predators or as a means of hunting food or finding members of the opposite sex in the dark. Cromie, William J. Exploring the Secrets of the Sea, Prentice-Hall, 1962. Klein, H. Arthur Bioluminescence, J. B. Lippincott Company, 1965. Yasso, Warren E. Oceanography, A Study of Inner Space, Holt, Rinehart and Winston, 1965. 77 293-387 0-687 64. What is the continental shelf? Officially, United States laws define the continental shelves as the seaward extention of the coast to a depth of 600 feet; this limit is set for the purpose of granting mineral rights, including oil drilling. The edge of the continental shelf, where the bottom begins to slope steeply, most commonly is found at depths between 360 and 480 feet. At the time the shelf received its name, it was thought to be essen- tially flat; now geologists know that the continental shelf has basins, ridges, and deep canyons. Compared to the deeper ocean floor, how- ever, the relief is gentle; hills and basins on the shelf usually do not ex- ceed 60 feet. The continental shelf width varies from practically nothing to several hundred miles. The shelf along the east coast of the United States is many times wider than that along the west coast. If all the continental shelves of the world are included, the average width is approximately 40 miles. The shelf slopes gently, at an average drop of 12 feet per mile, from the shore to the continental slope. In contrast, the grade of continental slopes is 100 to 500 feet per mile. CONTINENT SHELF About 7 percent of the ocean is underlain by continental shelves. These are the areas where intensive mineral exploration is now being con- ducted. Cromie, William J. Exploring the Secrets of the Sea, Prentice-Hall, 1962. Engel, Leonard, and Editors of LIFE The Sea, Life Nature Library, Time, Inc., 1961. Stewart, Harris B., Jr. Deep Challenge, Van Nostrand, 1966. 78 65. Has an efficient method of obtaining fresh water from sea water been invented? Compared to the cost of purifying fresh water, desalinization is not yet an efficient method of obtaining water for either drinking or irriga- tion. Only in a few water-poor areas is it now economical to desalinate sea water. As commercially practical plants reduce water costs, the con- sumption of water will increase, making the desalinization operation not only attractive but also essential. Use of water in the United States is increasing at the rate of 1.5 mil- lion gallons an hour! In many parts of the country water shortages are already critical. Recognizing this crisis, the U. S. Congress in 1952 passed the Saline Water Act; this Act established the Office of Saline Water and assigned to it the primary mission of developing practical low cost com- mercial ways to increase the supply of potable water. Using the best com- mercial methods available in 1952, the cost of producing 1,000 gallons of fresh water from sea water was more than 4 dollars. Today the cost is about 1 dollar; future cost of 20 to 30 cents per 1,000 gallons is con- sidered entirely possible. A nuclear powered plant is scheduled to begin operation in southern California in 1972. Capacity will be 150 million gallons per day plus 1,800 megawatts of electricity. This one plant will produce more fresh water than all the desalination plants operating throughout the world in 1966. There are a number of desalinization methods. Freezing of sea water leaves about one-third of the salts in pockets in the ice. Use of semi- permeable membranes, ion exchange, and salt-eating bacteria has been considered experimentally. Scripps Institution of Oceanography is 79 developing a multiple-effect sea water conversion system, which shows promise of producing fresh water for 20 cents per 1,000 gallons commercially. The oldest method, solar distillation, is not economical, because even in the Sahara the cost of a plant would be four times that of an evapora- tion plant using artificial heat. Nevertheless, there are areas in the world where small quantities of water are needed, but energy sources and technical competence are not available. In these areas the simple solar still may be a partial answer. Spiegler, K. S. Salt Water Purification, John Wiley and Sons, 1962. Stewart, Harris B., Jr. Deep Challenge, Van Nostrand, 1966. U.S. Department of the Interior Saline Water Conversion Report for 1965, Office of Saline Water, Washington, D. C., 1965. 80 66. Why is the Cape Hatteras area known as the graveyard of ships? Cape Hatteras has earned its reputation as a dangerous area because of a combination of factors: sudden storms, shifting sand bars, and strong currents. The name “Graveyard of Ships” or “Graveyard of the Atlantic’ was used by Alexander Hamilton, who as a young man sailed past the area. Later, he used his influence as Secretary of the Treasury to have a lighthouse built at Cape Hatteras. The Cape is exposed to severe storm winds; it is open to the sea from north through east to southwest. Storms strike with sudden intensity. Hurricanes have driven many ships onto the beaches and shoals. The sands of Hatteras Island extend seaward as gigantic shoals for a distance of 12 miles; at some places they reach almost to the surface. Sand bars on Diamond Shoals are constantly shifting. It is in this area that the southernmost portion of the Labrador Cur- rent meets the Gulf Stream. At times, the current has great velocity at Diamond Shoals; at other times there is no current or its direction may be reversed. With northerly and northeasterly winds a dangerous cross sea is usually encountered. Since the introduction of modern aids to navigation the reputation of Cape Hatteras has improved considerably, but the skeletons of many ships are reminders of its past. 81 Carney, Charles B. “Hatteras: Climate Setting for Year-round Recreation,’ Weather- wise, Vol. 18, No. 3, 1965. Lonsdale, Adrian L., and H. R. Kaplan A Guide to Sunken Ships in American Waters, Compass Publica- tions, 1964. 82 67. How does an oceanographic ship anchor to take observa- tions in the deep ocean? Although most oceanographic observations are made without anchor- ing, Oceanographic ships sometimes anchor in deep water for several hours, days, or weeks to measure subsurface currents or to obtain re- peated observations in one spot. The weight of the anchor need not be great, because the weight of cable lying on the bottom may be more than 2 tons. The Navy often uses anchors of 500 or 800 pounds, but Danforth anchors of only 40 pounds have been used to anchor in water a mile deep. In depths of 3,000 fathoms, wire tapering from 5/8 to 1/2 inch is normally used to lower the anchor. !n greater depths, the taper is from 3/4 to 3/8 inch. Free-fall anchors have been used for rapid anchoring in deep water. For example, in a recent mooring the total elapsed time for planting a 4,000-pound anchor at 17,250 feet was 16 minutes. No attempt was made to recover the cable and anchor. Even if a suitable winch had been available, the cost would have exceeded the value of the anchor and cable. To prevent a ship from swinging on its mooring, it may be anchored fore and aft or it may tie to a bridle arrangement of three or four anchored buoys. Pell, Claiborne (Senator) Challenge of the Seven Seas, William Morrow and Company, 1966. Sverdrup, H. U., Martin W. Johnson, and Richard H. Fleming The Oceans, Their Physics, Chemistry, and General Biology, Prentice-Hall, 1946. U.S. Naval Oceanographic Office Instruction Manual for Oceanographic Observations, H. O. Pub. No. 607, 1955. 83 e 68. How much power (energy) is in a wave? The kinetic energy in waves is tremendous. A 4-foot, 10-second wave striking a coast expends more than 35,000 horsepower per mile of coast. The power of waves can best be visualized by viewing the damage they cause. On the coast of Scotland, a block of cemented stone weighing 1,350 tons was broken loose and moved by waves. Five years later the replacement pier, weighing 2,600 tons, was carried away. Engineers have measured the force of breakers along this coast of Scotland at 6,000 pounds per square foot. Off the coast of Oregon, the roof of a lighthouse 91 feet above low water was damaged by a rock weighing 135 pounds. An attempt has been made to harness the energy of waves along the Algerian coast. Waves are funneled through a V-shaped concrete struc- ture into a reservoir. The water flowing out of the reservoir operates a turbine which generates power. Bowditch, Nathaniel American Practical Navigator, U. S. Naval Oceanographic Office, 1958. Deacon, G. E. R. (Ed.) Seas, Maps, and Men, Doubleday and Company, 1962. Williams, Jerome Oceanography, An Introduction to the Marine Sciences, Little, Brown and Company, 1962. 84 69. Are the rise and fall of tides used to develop power? Only in France are the tides used to develop power. There are many reasons why tidal power is not extensively used and probably won't be in the near future. There are only a few places in the world where the tidal range is great enough to justify building dams. Even if all these areas were utilized, they could supply only one-tenth of one percent of the world’s power requirements by the year 2000. Labor costs for such huge construction projects are prohibitively high. Perhaps some of the dams could have been built 30 years ago, but labor costs today make the projects financially unattractive. (4) SEA WATER INLET SLUICE GATE. HYDRO TURBINES OPEN POWER HOUSE @) BAY WATER INLET SLUICE GATE CLOSED SEA WATER AT HIGH TIDE SLUICE GATE CLOSED TLET SEA WATER OUTLET Sale (4) SLUICE GATE OPEN WHEN Sea WATER AT Low Tipe... SLUICE GATES N2 2&3 OPEN FOR BAY WATER TO FLOW OUT TO THE SEA. GATES N& 1&4 CLOSED WITHOUT STOPPAGE OF HYDRO-ELECTRIC GENERATORS BY MEANS OF TIDAL GATE CONTROLS. Tidal power cannot compete economically with power produced by nuclear fission and other methods. The main reason that tidal power is not used is simply that the need for additional power does not exist now. It is interesting to note that extensive use of tidal energy for power stations would bring about a noticeable change in tidal conditions. According to the French engineers Allard and Gibrat, if the utilization of tidal energy is brought to 2 billion kilowatts, the earth would slow its rotation so much that it would lag 24 hours every 2,000 years. Deacon, G. E. R. Seas, Maps, and Men, Doubleday and Company, 1962. Gaskell, T. F. World Beneath the Oceans, American Museum of Natural History. Pell, Claiborne (Senator) Challenge of the Seven Seas, William Morrow and Company, 1966. 85 70. Who is the most famous oceanographer? This is a difficult question. The scientists best known for their ex- ploits on and in the ocean have been explorers and aquanauts. Many men who have contributed most to oceanography are virtually unknown to the public. One man who was both an explorer and oceanographer was Fridtjof Nansen, a Norwegian who froze his ship, the FRAM, into the Arctic ice off the coast of Siberia to prove the theory that an ocean current would drift a ship across the Arctic Basin. During the 3-year drift he came within 360 miles of the North Pole and then proceeded by sledge to a point 226 miles from the Pole. He is the inventor of the Nansen bottle, which has been the basic oceanographic instrument for decades and is still widely used. A special museum in Oslo houses the FRAM and many other Nansen mementos, awards, and expedition materials. Lt. Matthew Fontaine Maury, USN, often called the father of Ameri- can oceanography, was the first man to undertake systematic study of the ocean as a full-time occupation and to write an English language textbook on oceanography. The present U. S. Naval Oceanographic Office is an outgrowth of the work he started before the Civil War. Two other Americans who contributed much to oceanography were William Beebe and Professor Henry Bigelow. Beebe, although best known for his work with the bathysphere in which he reached a depth of 3,028 feet in 1934, also directed a number of shipboard ocean- ographic surveys. During his long association with the Woods Hole Oceanographic Institution, Bigelow contributed greatly to the coordination of physical, chemical, and geological studies of the oceans, leading to a more com- plete understanding of the interrelationships of life in the sea. Many men who were famous for other reasons have been interested in study of the oceans. Included in the long list are Alexander the Great, Prince Albert of Monaco, Captain James Cook, Benjamin Franklin, and Commander Scott Carpenter. Deacon, G. E. R. (Ed.) Seas, Maps, and Men, Doubleday and Company, 1962. Dougherty, Charles M. Searchers of the Sea, Viking Press, 1961. Lyman, John “History of Oceanography,” Ocean Sciences, edited by Captain E. John Long, United States Naval Institute, 1964. 86 71. Does oceanography include the study of lakes and streams? The study of inland waters (lakes and streams) and the processes occurring in them is known as limnology rather than oceanography, but many of the methods of oceanography can be used in this study. It is concerned with the interrelationships of chemistry, physics, and geology and their effects on organisms. Processes such as sediment drift along shore are similar in lakes and oceans. Fish are affected by temperature changes in fresh water as well as in salt water. Pollution is a universal problem. In North America, oceanographers and limnologists have a joint society, the American Society of Limnology and Oceanography, which publishes the journal Limnology and Oceanography. Frey, David G. Limnology in North America, University of Wisconsin Press, 1963. Pincus, Howard J. Secrets of the Sea, Oceanography for Young Scientists, American Education Publications, Inc., 1966. Reid, George K. Ecology of Inland Waters and Estuaries, Reinhold, 1961. 87 72. What is plankton? The word “plankton” is derived from a Greek word meaning wander- ing. Plankton includes all sea animals and plants too small or weak todo anything but drift with the currents. The plants are known as phyto- plankton and the animals as zooplankton. Both are important food sources for fish and other animals. The single-celled plants known as diatoms make up more than half the plankton in the ocean. A cubic foot of sea water may contain 20,000 plants and only 120 animals or eggs. Phytoplankton uses the nutrient salts and minerals in sea water as food. It, in turn, is food for many animals, which are themselves part of the ‘food chain.” Plankton ‘‘blooms” in the spring when nutrient-rich bottom water is brought to the surface by storms. Longer days provide more light to - © t= (©) DIATOMS Sa % COPEPOD ACTUAL SIZE-—2.5™m RADIOLARIAN RADIVEARNnS stimulate plant growth and increase numbers rapidly. Phytoplankton may spread over miles of ocean, discoloring the water with shades of yellow, brown, or green. Many planktonic organisms are sensitive to changes in temperature and salinity. Sudden changes can cause mass mortality, not only to the plankton, but also to the animals that feed on it. Beside planktonic plants and animals, there is another group with some characteristics of each. This group includes the dinoflagellates which manufacture their own food, but also eat other organisms and have means of locomotion. 88 Deacon, G. E. R. (Ed.) Seas, Maps, and Men, Doubleday and Company, 1962. Engel, Leonard and Editors of LIFE. The Sea, Life Nature Library, Time, Inc., 1961. King, Cuchlaine A. M. Oceanography for Geographers, Edward Arnold Ltd. (London), 1962. 89 73. Are there really sea monsters? Although we discount the fabled sea monsters, such as the kraken which could swallow vessels whole, we have not yet explored the ocean thoroughly enough to say with absolute certainty that there are no monsters in the deep. Scientific observations and records note that giant squids with tentacles 40 feet long live at 1,500 feet and that sizable objects have been detected by explosive echo sounding at greater depths. Oarfish 40 to 50 feet long also have been observed by scientists. Either the oarfish or the giant squid with its long tentacles may have given rise to the sea serpent stories told by sailors of old. In recent years, Danish scientists have studied large eel larvae that would grow to 90 feet if their growth rate is the same as eels of other species. Helm, Thomas Monsters of the Deep, Dodd, Mead and Company, 1962. Knowlton, William Sea Monsters, Alfred A. Knopf, 1959. Miller, Robert C. The Sea, Random House, 1966. 90 74. What is sonar? The word “sonar” was coined from the term describing the opera- tion and functions of certain undersea equipment, “sound navigation and ranging.” Equipment using sound for underwater navigation and ranging is called sonar. It operates on the same principle as radar, but transmits sound waves instead of radio waves. Sonar may be either active or passive. In an active system, a sound is transmitted and the echo received. Distance is computed as one-half of elapsed time multi- plied by speed of sound in sea water. A passive system is a listening system, and only direction can be determined. The speed of sound is affected by water temperature, salinity, and pressure. An increase in any of these results in an increase in sound velocity. Sonar is used for submarine detection, navigation, fish finding, and depth determination. The depth finding sonar is commonly called a fathometer but the correct general name for a depth finding sonar is echo sounder. The word “‘Fathometer”’ is a registered trademark of the Raytheon Company and should be used to describe electronic sounders made by Raytheon only. Coombs, Charles Deep-Sea World, William Morrow and Company, 1966. Hull, Seabrook The Bountiful Sea, Prentice-Hall, 1964. U.S. Naval Oceanographic Office Oceanography and Underwater Sound for Naval Applications, Special Publication No. 84, October 1965. 91 75. How deep can submarines operate safely? The maximum operating depth of submarines is a military secret; however, the engineering facts that determine safe operating depths are well known. The bathyscaph 7TR/ESTE, which reached the deepest depth of the oceans, is no more like a true submarine than a stratosphere balloon is like an airplane. A true submersible should be positively buoyant and carry a considerable payload. A submarine built by today s methods to withstand a depth of 4,000 feet would not have sufficient buoyancy to carry a useful payload. Submersibles (not military submarines) have dived and operated under power at depths greater than 6,000 feet; AL V/N and ALUMINAUT are two of these. ALUMINAUT has a depth capability of 15,000 feet. Newer construction materials, such as filament-wound, glass-rein- forced plastic, produce high hull strength in respect to weight and may be used in the future for submersibles designed for deeper depths. According to Geo-Marine Technology magazine (March 1967), World War | submarines had a capability of 100—200 feet; World War I! submarines, 200—400 feet; and present day submarines, 750—1,500 feet. By 1970 the depth is expected to reach 4,000 feet; small, high- speed interceptor submarines may be capable of diving to 6,000 feet or more. Hull, Seabrook The Bountiful Sea, Prentice-Hall, 1964. Soule, Gardner The Ocean Adventure, Appleton-Century, 1966. 92 76. How do submarines navigate when submerged for weeks at a time? When the nuclear submarine VAUT/LUS made its famous voyage to the North Pole under the Arctic ice in 1958, the navigator was making use of Newton's second law of motion, F = MA (force equals mass times acceleration). The navigation system, known as inertial navigation, uses accelerometers to continuously sense changes in velocity with respect to a known starting point. Three gyroscopes (one for each direction of movement) create a platform which remains stabilized regardless of maneuvers of the sub- marine. The system is entirely independent of magnetic influences; this is an essential requirement in polar navigation. In addition to the inertial navigation system, submarines may rely on acoustic positioning sources on the bottom of the ocean to locate known points of reference, and they can make use of doppler sonar to deter- mine accurate ground speed. The whole doppler-inertial navigation system on a nuclear submarine is tied together by an electronic computer. Caidin, Martin Hydrospace, E. P. Dutton and Company, 1964. Sherwood, David A. “Acoustic Navigation Systems, ‘Undersea Technology, Vol. 5, No. 6, June 1964. Tilson, Seymour “The New Navigation,’ /nternational Science and Technology, July 1963. 93 293-387 O-68_8 77. How fast can a porpoise swim? Is it the fastest swimming “fish’’? Most porpoises can swim 17 to 23 miles per hour for short periods, although, to an observer aboard a ship, they may appear to be traveling much faster. There are records of porpoises being observed at 40 to 43 miles per hour, but they were swimming before a ship, utilizing the bow wave for extra speed. Much research has been done to discover just how the porpoise is able to accomplish its high swimming speed. Either it is a much more powerful swimmer than expected, or it modifies its shape and, there- fore, reduces hydrodynamic drag. The question is yet unsolved. Although the porpoise is a very fast swimmer, it is not the fastest sea animal. Marlin, bonito, and albacore have been reported to swim at speeds of 40 to 50 miles per hour. The sailfish and swordfish have at- tained speeds of 60 miles per hour. Alpers, Antony Dolphins: The Myth and the Mammal, Houghton Mifflin Com- pany, 1961. Lagler, Karl F., J.E. Bardach, and R. R. Miller Ichthyology, John Wiley and Sons, 1962. Norris, Kenneth S. Whales, Dolphins, and Porpoises, University of California Press, Berkeley and Los Angeles, 1966. 94 ee 78. What is the pressure at the deepest part of the ocean? The pressure at the deepest part of the ocean is close to 7 tons per square inch, almost a thousand times the atmospheric pressure on the earth's surface. At a depth of 3,000 feet, a pressure of 8,100 pounds per square inch is sufficient to squeeze a block of wood to half its volume so that it will sink. Ata depth of 20,000 feet, air will be compressed so much that it will weigh as much as the surrounding water. Bowditch, Nathaniel American Practical Navigator, U. S. Naval Oceanographic Office, 1958. Carrington, Richard A Biography of the Sea, Basic Books, 1960. Stewart, Harris B., Jr. Deep Challenge, Van Nostrand, 1966. 95 79. What are turbidity currents? Turbidity currents occur when sediments on the continental slope are dislodged by earthquakes and begin sliding down the slope. A cur- rent is created by the increased density of the sediment-laden water. This current, in turn, dislodges more sediment which continues down- slope at greater speed. Turbidity currents have broken off series of submarine cables; the time between the cable breaks enables one to compute their approxi- mate speed. If the slope is steep and long, the speed may reach 50 miles per hour. The sediment-laden currents cause scouring of the sea floor; it is believed that they contribute to the flushing and erosion of submarine canyons. If the turbulence is sufficient to keep sediments in suspension, turbidity currents may flow for great distances; the sediments are finally deposited on the abyssal plains. Cowan, Robert C. Frontiers of the Sea, Doubleday and Company, 1962. Deacon, G.E. R. Seas, Maps, and Men, Doubleday and Company, 1962. Gaskell, T. F. World Beneath the Oceans, American Museum of Natural History, 1964. 96 80. What is the most important discovery made about the oceans? One of the most important discoveries about the oceans is the true nature of the sea floor. Not so long ago it was generally believed that much of the deep ocean floor was a featureless plain. We now know that there are numerous mountains under the sea, some of them higher than Mt. Everest. But perhaps the most striking discovery is that all oceans except the North Pacific are divided in the center by an almost con- tinuous system of mountains. Some of the other important discoveries are: Discovery in 1938 of the coelacanth, a fish thought to have become extinct 50 to 70 million years ago, but which was found to be thriving off South Africa. Discovery of a layer of living organisms spread over much of the oceans at a depth of several hundred fathoms (deep scattering layer). Discovery of nodules of manganese, cobalt, iron, and nickel which can be dredged from the sea floor. Discovery that the earth’s crust is much thinner under the sea than under the land and that the bed of the ocean is underlain by basalt rather than by granite which makes up the continents. ' Discovery of a deep sound channel that carries sounds for thousands of miles. Discovery of life in the deepest parts of the oceans. Perhaps the most important recent discovery is that man can live and work in the ocean for extended periods of time. Captain George F. Bond, a medical officer in the United States Navy, discovered that, once a diver's blood has become saturated with breathing gases at a given depth, decompression time is related only to the depth and not to the length of time the diver remains there. This led to the concept of under- water habitation by Cousteau and Link. Carson, R. L. The Sea Around Us, Oxford University Press, 1951: Mentor Books (Paperback), 1954. Engel, Leonard, and Editors of LIFE The Sea, Life Nature Library, Time, Inc., 1961. 97 81. What is the MOHO? MOHO is the name commonly used for the Mohorovicic dis- continuity, the boundary between the earth’s crust and mantle. It was named from the Yugoslav seismologist who discovered its existence. The crust is the surface layer of rock, averaging 125,000 feet in thickness under the continents; under the oceans it is only 15,000 to 20,000 feet thick. This is why the planned Mohole was to be drilled through the ocean floor. At the Mohorovicic discontinuity, the speed of earthquake waves changes abruptly, indicating a difference between rocks of the crust and of the mantle. f The objective of the Mohole Project (now discontinued) was to drill through the MOHO and obtain samples of the mantle rock. Some of the questions which led to the project are: How did the rocks of the oceanic crust become separated from the rocks of the continental crust? How was the crust differentiated? And from where did the layers of oceanic crust come? Achievements that arose from the Mohole Project included develop- ment of ways to core the ocean bottom in deep water, a better under- standing of the geophysics of several ocean areas, and improvement of drilling instruments and techniques. Bascom, Willard A Hole in the Bottom of the Sea, Doubleday, 1961. Ericson, David B. and Goesta Wollin The Deep and the Past, Alfred A. Knopf, 1964. Yasso, Warren E. Oceanography, A Study of Inner Space, Holt, Rinehart and Winston, 1965. 98 82. How much do scientists really know about the oceans? Every question answered about the oceans leads to additional ques- tions that demand answers, so it can safely be said that our present knowledge is very small. Charting of the ocean floor is one thing that can be expressed in per- centage. Not more than five percent of the world’s ocean floor has been charted with any degree of reliability and most of this was done during the International Geophysical Year (1957-58). Our ability to predict the ocean environment is still small and largely restricted to predicting wave height and conditions for sound trans- mission. Among the unanswered questions are the following: Where can more fish for food be found? The Southern Hemisphere is largely unexploited. Are there still unknown animals in the sea? The coelecanth (question 80) was unknown except as fossils until 1938. Will “farming’’ the ocean increase our food supply without disturb- ing the balance of nature? Were the Eastern and Western Hemispheres split apart millions of years ago as the contours of their present shorelines suggest? " What causes the lateral meanders in the path of the Gulf Stream? How much pollution, radioactive and other, can the sea dissipate without turning into a ‘desert’? Can a practical method of using plankton for food be found? And, perhaps most important, can the nations of the world learn to use the ocean and its resources cooperatively? There have been many disputes over fishing rights; disputes over mineral rights on the continen- tal shelves will follow unless international agreements are made and adhered to. Coombs, Charles Deep-Sea World, William Morrow and Company, 1966. Pell, Claiborne (Senator) Challenge of the Seven Seas, William Morrow and Company, 1966. Woods Hole Oceanographic Institution Research in the Sea, 1967. 99 83. What are ice islands? Ice islands are thick masses of ice which have broken from the ice shelves of Greenland, Ellesmere Island, or other northern islands. They have been used as drifting stations for oceanographic and meteorological studies. Ice floes of frozen sea water have also been used as scientific stations, but they usually last only a year or two. The Russians have been manning ice stations in the Arctic since the mid-1930's; by 1958 they had airlifted 565 temporary scientific sta- tions onto Arctic Ocean pack ice. The U. S. station Fletcher's Ice Island (T-3) has been used as a re- search station since 1952. It drifts clockwise around the Arctic Ocean. Another ice island, ARLIS Il, was manned from May 1961 to May 1965. Cromie, William J. Exploring the Secrets of the Sea, Prentice-Hall, 1962. Thomas, Lowell, Jr. “Scientists Ride Ice Islands on Arctic Odysseys,’’ National Geo- graphic, Vol. 128, No. 5, Nov. 1965. Weeks, Tim, and Romona Maher Ice Island, The John Day Company, 1965. 100 84. What are the best materials to use for building a pier? Because piers are constructed and used in all geographic climates and because of the variety of marine conditions that piers are exposed to, experts hesitate to recommend a universal “‘best material” for piers and other marine constructions. Piers and harbor and shore constructions are subjected to corrosion, abrasion, marine borers, and fouling. Since World War II, extensive per- formance and service life tests of the basic heavy structural materials— timber, concrete, and steel—have been undertaken in hundreds of loca- tions; on these basic materials an infinite number of paints, adhesive coatings, impregnations, and protective coverings have been tested. There is no structural material that can be guaranteed to withstand the extreme forces and pressures of waves generated by a hurricane or of sea ice driven by wind and current. Results of experiments using steel piles for shore protection show the greatest deterioration at the beach surface. The corrosion created by the salt spray, combined with the constant ‘‘sanding’ movement of the beach, causes this location on the pile to erode 10 times faster than any other. _ In many cases, galvanic protection is given to steel piers. Galvanic corrosion occurs because sea water is a good electrolyte; the system acts on the same principle as a battery. Mill scale and other chemical and physical differences in steel cause it to act as a bimetallic, setting up an anode and a cathode in the electrolyte (sea water). Corrosion protec- tion is afforded by attaching magnesium, aluminum, or zinc oxide bars below the level of mean low water; direct current using scrap steel or graphite anodes can be used to give the same protection. Certain marine mollusks and crustaceans cause extensive damage to timber structures in sea water each year. The mollusks as larvae enter the timber through a small hole and grow to full size inside the wood; crustaceans destroy the surface, burrowing very close together and creating a system of interlacing holes that weaken the wood and permit waves and currents to break off the damaged wood and carry it away. Cases are recorded where untreated piles 16 inches in diameter have been severed in 6 months and creosote-treated piles needed replacement in 2 years! Such destruction has been reported in widely different geo- graphic locations—Puerto Rico, Florida, Newfoundland, California, New York, and Alaska. Two common methods of pile protection are creo- sote pressure treatment and use of precast concrete jackets. The value of the latter covering is questionable, since marine borers are also known 101 to attack low-grade concrete and soft stone. Certain tropical woods, such as Greenheart found in British Guiana, have a natural resistance to marine borers, but most woods must be protected. Concrete structures tend to “grow” in sea water. A case on record cites a 13-foot-diameter concrete cylinder that increased 6 inches in di- ameter and 4 inches in height. In another case, a steel cylinder of 1/4- inch steel plate filled with concrete ‘grew’, causing the plates to rupture. High-silica-cement piles covered or impregnated with asphalt have proven quite satisfactory; an engineering report on piers built with these specifications indicates that they were in excellent condition after 10 years of exposure and use. Woods Hole Oceanographic Institution Marine Fouling and Its Prevention, Annapolis, Maryland, U. S. Naval Institute, 1952. Morgan, J. H. Cathodic Protection, Its Theory and Practice in the Prevention Of Corrosion, Macmillan Company, 1960. 102 85. What is the hydrologic cycle? The oceans are the vast reservoir from which moisture is drawn to furnish precipitation to the land. Even inland areas, such as the Missouri-Mississippi drainage area, receive up to 90 percent of their precipitation from water that has evaporated from the sea surface. It has been estimated that about 9,000 cubic miles of water fall on the land surface of the earth each year. This water dissolves minerals from the earth and carries them, along with sediments, to the ocean. Rain water may return to the ocean directly through streams or rivers or more slowly through subsurface percolation. Part of the water may be withdrawn from the cycle for extended periods by being locked up as ice, and some evaporates back to the atmosphere and falls again as rain or snow. Thus, the essence of the cycle is the progressive transformation and movement of water through evaporation, precipitation, runoff, and return to the sea. Rane PIR ATION EVAPORATION 4 Mol IStORe ROM 4 So y King, Cuchlain A. M. Oceanography for Geographers, Edward Arnold Ltd. (London), 1962. Pincus, Howard J. Secrets of the Sea, Oceanography for Young Scientists, American Education Publications, Inc., 1966. 103 86. What is the DSL? The deep scattering layer (DSL) is a widespread layer of living organisms that scatter or reflect sound pulses. During the day, this layer has been reported at depths of 700 to 2,400 feet, but most often between depths of 1,000 and 1,500 feet; at night, the layer moves to or near the surface. Existence of the DSL has been reported from almost all deep ocean areas, except the Arctic, Antarctic, and some areas of the Central South Pacific. The types of organisms making up the deep scattering layer are still not definitely known. They may be fish, shrimplike crustaceans, or squid. Attempts to collect and photograph the organisms have been inconclusive. The DSL produces a phantom bottom on echograms, which probably accounts for the charting of nonexistent shoals in the early days of echo sounders. Dietz, Robert S. “The Sea's Deep Scattering Layer,’’ Scientific American, Vol. 207, No. 2, Aug. 1962. Soule, Gardner The Ocean Adventure, Appleton-Century, 1966. U.S. Naval Oceanographic Office Science and the Sea, Washington, D. C., 1967. 104 87. How thick is the sediment at the bottom of the ocean? Seismic refraction and reflection methods have enabled geophysicists to make reliable estimates of the average thickness of unconsolidated sediments on the ocean floor. Sediments in the Atlantic are about 750 meters thick. The rate of deposition in the Pacific appears to be much slower (see question 4); the thickness of red clay sediment in deep basins of the Pacific has been found to be 100 to 200 meters. The average thickness of sediments in the Pacific is about 300 meters. Basins of the Indian Ocean have about the same sediment thickness as those of the Pacific. Calcareous deposits in equatorial regions average 400 meters in thickness. Most sediments (sand, mud, and clay) come from the land; therefore, the thickest deposits of sediments are near land. Thickness as great as 4,000 meters has been measured close to large land masses. Cowan, Robert C. Frontiers of the Sea, Doubleday and Company, 1960. Ericson, David B., and Goesta Wollin The Deep and the Past, Alfred A. Knopf, 1964. Gaskell, T. F. World Beneath the Oceans, American Museum of Natural History, 1964. 105 88. What is a storm surge? A storm surge is caused by a combination of meteorological and astronomical factors. Gravitational effects of the moon and sun pro- duce tides. Storms, and particularly hurricanes, may raise the normal tide level by several feet. High winds blowing from one direction for a prolonged period (usually 10-12 hours or more) can physically “pile up” water on shore (or move it off shore). The effect is particularly notice- able, and most dramatic and hazardous, along shorelines of estuaries and semienclosed seas. This amounts to transport of a substantial volume of water by the frictional meshing of two fluids—air and water. When storms occur during times of highest tides, the results may be disastrous. When the water level is raised, higher waves can result from the com- bination of greater depth and strong winds. The storm surge resulting from a hurricane can last through one or two tidal cycles. In 1953, a storm surge occurring at a time of particularly high tides flooded the coast of Holland, killing more than 1,800 people. The same storm surge killed more than 300 people in England. Since that time, a flood warning service has been set up in Britain to forecast the probable height of a surge 12 hours before it strikes. Deacon, G. E. R. (Ed.) Seas, Maps, and Men, Doubleday and Company, 1962. Dunn, G. E., and B. |. Miller Atlantic Hurricanes, Louisiana State University Press, New Orleans, 1960. Gaskell, T. F. World Beneath the Oceans, American Museum of Natural History, 1964. 106 ee 89. What makes a very slight swell (wave) become much higher when it breaks on the shore as surf? Until a wave approaches the shore, its height is usually about one- twentieth its length (distance from crest to crest); thus, if the crests are 20 feet apart, the wave height would be 1 foot. When the water depth equals half the wave length, bottom friction begins to slow down the speed of advance. With a wave length of 20 feet, this would take place when the water depth is 10 feet. As the wave slows, the back of the wave crowds the front, piling the water higher. The lower part of a wave, being nearest the bottom, is slowed more than the top; as a result, the top begins to curl over. When the wave height reaches three-fourths the water depth, the wave topples over as a breaker. Bowditch, Nathaniel American Practical Navigator, U. S. Naval Oceanographic Office, 1958. Deacon, G. E. R. (Ed.) Seas, Maps, and Men, Doubleday and Company, 1962. Engel, Leonard and Editors of LIFE The Sea, Life Nature Library, Time, Inc., 1961. 107 90. What is “ship route forecasting’’? The shortest route between two points on the globe is a great-circle track; however, because of sea conditions, it is not always the fastest or safest. In one year (1954), more than 6 percent of the world’s shipping experienced weather damage. Another 3 percent was involved in col- lisions, some of which were caused at least partly by weather condi- tions. In the early 1950's, the U.S. Navy established a ship routing service which isa modern version of the service provided by Lt. Matthew Maury before the Civil War, when he gathered the logs of ships and produced charts of ocean currents and winds. Maury swork resulted in saving days or weeks in the journeys of sailing vessels; now time savings are meas- ured in hours. By 1958, it was found that the travel time of Military Sea Transport Service ships from New York to Bremerhaven had been reduced from 10 days to 9. The principles of ship routing are simple. Marine meteorologists pre- dict wind speeds and direction for the area of interest. A chart is pre- pared to show lines of equal wind velocity and these are translated into charts of expected wave heights. By use of these charts maximum attain- able speed can be computed for any type of ship. A ship using this service maintains communication with the individual supplying the routing service and receives a daily course to be steered. Although ship route forecasting was developed by the military, pri- vate forecasters furnish the same service to commercial ships. James, Richard W. Application of Wave Forecasts to Marine Navigation, Special Publi- cation No. 1, U.S. Naval Oceanographic Office, July 1957. Marcus, Sidney O., Jr. “The United States Navy Hydrographic Office Ship Routing Pro- gram,” Transactions of the New York Academy of Sciences, Vol. 21, No. 4, February 1959. 108 Se ee ee ee 91. How accurately can oceanographers predict ice formation, size, and movement? The accuracy of ice forecasting depends on the locale, details re- quired, time range of the prediction, and accuracy of the input weather information. Ice formation predictions are based on heat content and salinity of the water mass, currents, and expected heat exchange from water to atmosphere (weather prediction and climatology). The required heat, salinity, and current information is obtained by oceanographers aboard icebreaker survey ships when the ice coverage of the sea is at its annual minimum. From ocean data so obtained, the ‘‘ice potential” of the water can be determined. With a known ice potential and expected air temperature data applied to the basic laws of thermodynamics one can derive the ice formation forecast’. In the far north, long-range predictions of ice formation are accurate within 2 to 4 days. Farther south, however, where the environmental conditions tend to be more variable, the formation predictions are accu- rate within 8 to 12 days. Size of the ice pack varies relatively little from year to year in the general area. Variations occur mostly on the southernmost fringes where shipping must travel; here variations are of critical importance. Predic- tions of the size of the pack are therefore generally quite accurate, but the predictions of ice in the shipping lanes need to be improved. The movement of ice in and out of shipping lanes, or leads, depends substantially on the wind; therefore the accuracy of an ice forecast is de- pendent on a good wind forecast. An accurate 48-hour to 5-day ice fore- cast is possible because meteorologists can produce reasonably good wind forecasts. For long-range (seasonal) ice prediction, which must be based in part on the area climatology, the dates for opening or closing of leads on the Labrador coast may be in error by as much as 6 weeks. Recently the problem of predicting ‘‘heavy ice’ and ‘‘open’’ areas in the polar ice pack for submarine operations has been tackled by oceanographers using aerial and submarine surveys and wind climatology. Oak, W. W. and H. V. Myers “Ice Reporting on the Great Lakes,’’ Weatherwise, Vol. 6, No. 1, Feb. 1953. Perchal, R. J. and S. O. Marcus “The U.S. Navy Hydrographic Office Ice Observing and Forecasting Program,’’ Mariners Weather Log, Vol. 5, No. 6, Nov. 1961. Wittmann, W. |. “Polar Oceanography,’’ Ocean Sciences, edited by Capt. E. John Long, U.S. Naval Institute, Annapolis, 1964. 109 293-387 O-68—9 92. What is the International Ice Patrol? The menace of icebergs to shipping was brought starkly to public attention on April 14, 1912, when the “unsinkable” ship 7/TANIC smashed into an iceberg off Newfoundland and sank with the loss of 1,500 lives. As a direct result of this tragedy, the International Ice Patrol was established; since that time not a single life has been lost through collision with icebergs in North Atlantic shipping lanes. Seventeen nations contribute to the funding of the Patrol, which is conducted by aircraft and ships of the U.S. Coast Guard. Despite man’s knowledge of icebergs, his best defense against them is still to track their movements and broadcast warnings. Attempts to destroy icebergs by firebombs, gunfire, and chemicals have all met with failure. Ice surveillance begins early in March when Coast Guard aircraft begin flying from Argentia, Newfoundland, and continues through June or July. The average number of icebergs drifting past Newfoundland each year is 400, although the number varies from less than a dozen to more than a thousand. | Icebergs that break off from glaciers of the Greenland icecap are first carried northward along west Greenland. They then turn westward and are carried southward by the Labrador current. The average time between breakoff and entry into the shipping lanes is 3 years. In order to understand the forces of nature that influence the drift of icebergs, oceanographers of the Coast Guard make studies of the origin of icebergs, yearly crop and drift patterns, currents, waves, and meteorological factors. The Coast Guard is now using a computer 110 aboard the oceanographic vessel EVERGREEN to aid in predicting the speed and course of icebergs drifting in the shipping lanes of the North Atlantic. Bowditch, Nathaniel American Practical Navigator, U. S. Naval Oceanographic Office. 1958. Kaplan, H. R. “The International Ice Patrol—A Memorial to the Titanic,’’ Mariners Weather Log, Vol. \!, No. 3, May 1967. 111 93. Who owns the water areas offshore and how far? Ownership of offshore waters is one of the major problems to be re- solved before the sea can be exploited peacefully. No country owns the floor of the open ocean. In the past, the traditional limit was 3 nautical miles, the effective distance a cannonball could be fired in the days of sailing vessels. Now nations choose a distance between 3 and 12 miles from their shores. Within these limits they may exercise control of shipping; there is, however, no clear requirement for other nations to recognize this sovereignty. The United States recently changed its territorial water claim from 3 to 12 miles. Although waters were orig- inally designated territorial for defense purposes, nations are now also concerned with pro- tecting their fishing and min- eral rights. The continental shelves are important for fu- ture harvest of marine life and minerals. The Geneva Convention of 1958 provides for a nation the sovereignty over its continental shelf to a depth of 200 meters or to the depth of exploitation of natural resources. Several Latin American countries have made claims of exclusive fishing rights to a distance of 200 miles from their coasts. Burke, William T. “Legal Aspects of Ocean Exploitation,”” Transactions of the 2nd Annual MTS Conference, Marine Technology Society, Washington, D. C., 1966. Pell, Claiborne (Senator) Challenge of the Seven Seas, William Morrow and Company, 1966. U.S. Department ot State Sovereigntv of the Sea, Geographic Bulletin No. 3, April 1955. 112 94. Is there any danger of overfishing? In some areas of the world, overfishing is already a problem for some species. Stocks have been depleted in heavily fished areas such as the continental shelves of Europe, particularly the North Sea. Cessation of fishing during two World Wars proved that a decrease in fishing could result in an increase in the number of large specimens. The U. S. Bureau of Commercial Fisheries has listed the following species as being seriously depleted: Pacific sardine, Atlantic salmon, Atlantic sturgeon, blue whale, fin whale, Atlantic shad, sperm whale, humpback whale, oyster, and sea otter. Depletion of these species is not caused entirely by overfishing; disease, predators, and water pollu- tion all take their toll. When the catch of a species reaches the point where the reproductive capacity is unable to compensate for the losses sustained, the species is headed for extinction. However, before this point is reached, operation of fisheries becomes unecanomical, and fishing of many species to extinction is thus prevented. There is little agreement among fisheries experts on how much the world’s fisheries could be increased. Estimates of the percentage of po- tential yield have varied from 1 percent to 75 percent. Undoubtedly the fish catch could be increased through exploitation of areas in the Southern Hemisphere and through fishing for species not now widely used for food. Pell, Claiborne (Senator) Challenge of the Seven Seas, William Morrow and Company, 1966. U.S. Naval Oceanographic Office Science and the Sea, Washington, D. C., 1967. Van Camp Sea Food Company Potential Resources of the Ocean, Long Beach, California, 1965. 113 95. Are radioactive wastes disposed in the ocean? If so, where and how, and are there any latent dangers involved? Radioactive wastes in concentrations considered harmful to man are contained in storage tanks on land; only low-level concentrations are disposed in the ocean in sealed containers. Nuclear generators of electricity will produce large quantities of low- level radioactive wastes. The sea has a great capacity for dispersing con- taminants; however, certain marine organisms have the capacity to con- centrate radioactive and other materials, even in an environment with low levels of concentration. Clams and other sessile (permanently attached) organisms eaten by man concentrate strontium-90 in their bodies; fish also concentrate the material in their bodies. Local game and fish authorities should be consulted before consumption of organ- isms taken from waters containing even low-level radioactive con- taminants. Some Russian scientists are of the opinion that disposal of radio- active waste in the sea is potentially harmful, especially if it reaches the sea at times when fish eggs are developing. While this view is not shared by all scientists, it does nevertheless suggest a latent danger: any disposal of radioactive materials in the sea is potentially hazardous. The study of organism uptake and concentra- tion of elements in sea water to such an extent that they may become inedible is a subject that promises to receive increasing attention and study by health and Government scientists and authorities. Cowan, Robert C. Frontiers of the Sea, Doubleday and Company, 1960. Stewart, Harris B., Jr. Deep Challenge, Van Nostrand, 1966. Williams, Jerome Oceanography, An Introduction to the Marine Sciences, Little, Brown and Company, 1962. 114 96. Why isn’t there more interest and activity in recovery of sunken ships and treasure? There is a great deal of interest in sunken ships and treasures, not only among professional salvors, but also among historical researchers and adventurers, including the armchair variety. From the beginning of time, men have been fascinated by the thought of getting rich quickly; but, for every successful treasure hunter, there are hundreds who don’t even meet expenses. Unquestionably, gold worth millions of dollars lies on the bottom of the ocean. It has been estimated that 150 million dollars worth of treasure from Spanish ships which sank while crossing from the Caribbean to Spain has never been salvaged. The availability of scuba gear has opened the search beneath the sea to amateurs. Those who search in shallow water (less than 65 feet) are almost certain to be disappointed; most treasure ships in these depths were located and salvaged soon after their loss. Waters between 65 feet and 200 feet deep (the effective working depth of scuba gear) offer most hope of finding treasure without ex- penditure of large capital. The hazards of salvage operations in deep water are great, and professional salvors must have a substantive margin of potential profits, because bad weather and equipment breakdown can make the operation expensive. Old wrecks are nearly always covered by coral, sand, and mud. Poor visibility adds to the difficulty of salvage Operations. Traditionally, there is an old shark guarding every treasure. 115 There are fabulous true stories, such as the success of Wagner and Associates, who have recovered more than a million dollars in treasure from Spanish ships off the coast of Florida. Perhaps there would be more such stories if it were not for the fact that successful treasure hunters are often closemouthed. Not all the treasures on the ocean bottom are gold and silver. When the ANDREA DORIA sank in 240 feet of water in 1956, she carried with her irreplaceable paintings of Rembrandt, which may still be un- damaged by salt water. A life-size bronze statue of Admiral Doria has already been salvaged. Two ships which sailed the seas many years ago will become national treasures of their respective countries when salvage and renovation are completed. The VASA, which sank in Stockholm (Sweden) harbor on her maiden voyage in 1628, was raised in 1961 and is now being re- stored. Eventually, the VASA and the artifacts found aboard will reside in their own seaside museum. In the United States, work is actively proceeding to raise from Mobile Bay (Alabama) the Yankee Civil War ironsided monitor known officially as USS TECUMSEH. Some objects have already been recovered from the ship, but many more museum pieces are expected to be located when the ship surfaces. When re- stored, the USS TECUMSEH will become a prize historic relic in the Smithsonian collection. Both ship and artifacts are valued beyond any price. Lonsdale, Adrian L., and H. R. Kaplan A Guide to Sunken Ships in American Waters, Compass Publications, 1964. Potter, John S.., Jr. The Treasure Diver’s Guide, Doubleday and Company, 1960. Wagner, Kip “Drowned Galleons Yield Spanish Gold,’ National Geographic, Vol. 127, No. 1, January 1965. 116 97. What types of organisms, other than sharks, are potentially dangerous to swimmers? The most dangerous animal other than sharks is probably the barra- cuda; indeed it is feared more than sharks by West Indian divers. Its usual length is only 4 to 6 feet, but it is aggressive, fast, and armed with a combination of long canines and small teeth capable of cutting as cleanly as a knife. Although no authentic record of deliberate attacks on man exists, the killer whale is potentially more dangerous than either sharks or barracudas. This carnivore measures 15 to 20 feet and hunts in packs. It attacks, seals, walruses, porpoises, and even baleen whales. The moray eel, which is as long as 10 feet, lurks in holes in coral reefs and may inflict severe lacerations on a diver who pokes his hand into its hiding place, or it may grasp the diver in its bulldoglike grip until he drowns. The octopus is probably overrated as a villain because of its evil appearance; nevertheless, its bite is poisonous. The giant squid has been known to pull man beneath the water to his death. The Portuguese man- of-war has tentacles up to 50 feet long with stinging cells which are painful to a swimmer brushing against them. There is a large group of animals dangerous to swimmers or waders who step on them. These include the sting ray, stonefish, zebra fish, toadfish, and many others. The giant tropical clam (7Tridacna), weighing as much as 500 pounds, has been depicted as trapping divers; however, no authentic records exist. Cromie, William J. The Living World of the Sea, Prentice-Hall, 1966. Engel, Leonard and Editors of LIFE The Sea, Life Nature Library, Time, Inc., 1961. Herald, Earl S. Living Fishes of the World, Doubleday, 1961. 117 98. How much electricity does an electric eel generate? Although the electric eel (which isn't a true eel) is the best known generator of electricity, there are at least 500 kinds of fishes that gener- ate. appreciable amounts of electricity. The electrical discharge serves to stun prey and repel attackers. The average discharge is more than 350 volts, but discharges as high as 650 volts have been measured. Current is low, usually a fraction of an ampere; however, brief discharges of 500 volts at 2 amperes have been measured, producing 1,000 watts. Although direct current is produced, it may be discharged as frequently as 300 times a second. Severity of the shock depends on the size and state of health of the fish. Voltage increases until the eel reaches a total length of about 3 feet; after that, only amperage increases. Electric eels in South American waters have been known to grow to a length of almost 10 feet. Other electric fish are found in other parts of the world. Cromie, William J. The Living World of the Sea, Prentice-Hall, 1966. Herald, Earl S. Living Fishes of the World, Doubleday and Company, 1961. 118 99. How are ships protected from corrosion and fouling? In the days of wooden ships, copper sheathing was used for protec- tion against fouling organisms because of its toxic properties. It served the additional purpose of protecting the hull against borers. By 1783 all English vessels were copper sheathed, and by the early 1800's the French and Spanish had followed suit. Copper sheathing has now been replaced by coatings and paints, many of which contain copper. Be- cause the toxic material must dissolve fast enough to prevent attach- ment, these coatings must be renewed periodically. Before World War II, development of antifouling coatings was on a trial-and-error basis. During the war, oceanographers of the Woods Hole Oceanographic Institution worked with the U. S. Navy to learn how marine paint actually works and which compounds are most effective at the least cost. Their research saved millions of dollars by cutting the cost of paints, lengthening the stay out of dry dock, and saving fuel. The Navy attributed a 10-percent fuel bill reduction to the improved anti- fouling paints. Corrosion of ships’ hulls is prevented by organic coatings or cathodic protection. Sea water is very corrosive, and the copper and mercury compounds used in antifouling paints, if not isolated from the hull, may accelerate corrosion. The most widely used anticorrosive compounds are vinyls, epoxies, and combinations of epoxy and coal tar. Fiberglass coatings are being tested. When a metal corrodes, metal ions enter the electrolyte (sea water) at the anode, leaving behind electrons which flow to the cathode through the metal. In cathodic protection, the corrosion potential of the hull is made more electronegative and the direction of flow is reversed at the sacrifice of the cathodic metal. Nowacki, Louis J., and Walter K. Boyd Metals Protection in the Marine Environment, Battelle Technical Review, June 1964. Turner, Harry J., Jr. “A Practical Approach to Marine Fouling,”” Geo-Marine Technology, Vol. 3, No. 3, March 1967. 119 100. What causes the hydrogen sulphide concentration at the bottom of the Black Sea? The Black Sea is landlocked with only a narrow, shallow outlet to the Mediterranean Sea. Asa result of its configuration, the bottom water is stagnant. Although the surface water is well oxygenated and teeming with life, water below the depth of about 200 meters contains no oxygen and is inhabited only by bacteria that decompose organic matter drift- ing down from above. Decomposition of organic material on the bottom uses up any avail- able oxygen so that hydrogen sulphide is concentrated in a thick layer of bottom water. This hydrogen sulphide colors the black mud on the sea floor. Similar conditions occur in those Norwegian fiords that are separated from the open ocean by shallow sills. Miller, Robert C. The Sea, Random House, 1966. Sverdrup, H. V., Martin W. Johnson, and Richard H. Fleming The Oceans, Their Physics, Chemistry and General Biology, Prentice- Hall, 1946. 120 They that go down to the sea in ships, That do business in great waters, These see the works of the LORD, And His wonders in the deep. — Psalms 107:23-24 121 U.S. GOVERNMENT PRINTING OFFICE : 1968 O0—293-387 Rit ba ; um he rhs Ue i f \ :) 7 i eae Hie irae ; : chee gi axial é \ Rete Pe a a Rane os: 4 ‘ aes Seo a3 bintoly ah side a 5 coy hai ek Le ape deieteey, Urey ae pew, eh oe Pant, CoP rh Ay Vert i i fi h (ot int \ 6" ' i i ¢i i ) ) ono | At, cote ' Tae i i , & 1 ’ Ti " i | Ti “y i ) ? 4 Z A J it ad 2. i Vom af iz ; ae : oy fie oe 4 y phy >i ‘ \ | os ey | \ , 1 ‘ a « = mn #. ‘9 an a nt oh TUB De “eon i ERRATA Page 112, paragraph 2, lines 4 and 5 should read: "The United States territorial sea claim is 3 miles, but the fishing limits were recently changed to 12 miles." Page 112, last line on page should read: "Sovereignty of the Sea," Geographic Bulletin No. 3S, April’ 1965). in RN Sy aa PRY Ber yt oud oA ras They iS, NG Wt eae ge Sree SRO eas ae ee aoe Se a Ay cane WINES aoa