NPS ARCHIVE 1967 BIRCH ETT, J. : TEMPERATURE-SALINITY RELATIONSHIPS IN THE SURFACE LAYERS OF THE EASTERN GULF OF MEXICO IN AUGUST 1966 A Thesis By JOHN ALEXANDER KLEIN BIRCHETT III Lieutenant, United States Navy Submitted to the Graduate College of the Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE May 1967 Major Subject: PHYSICAL OCEANOGRAPHY LIBRARY ntinnv NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIF. 93940 TEMPERATURE-SALINITY RELATIONSHIPS IN THE SURFACE LAYERS OF THE EASTERN GULF OF MEXICO IN AUGUST 1966 A Thesis By JOHN. ALEXANDER KLEIN BIRCHETT III u Lieutenant, United States Navy Submitted to the Graduate College of the Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE May 1967 Major Subject: Physical Oceanography ft£; iWrr-S^W LIBRARY NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIF. 93940 TEMPERATURE-SALINITY RELATIONSHIPS IN THE SURFACE LAYERS OF THE EASTERN GULF OF MEXICO IN AUGUST 1966 A Thesis By JOHN ALEXANDER KLEIN BIRCHETT III Lieutenant, United States Navy Approved as to style and content by: (Chairman of Committee) (Head of Department) (Member) (Member) May 1967 iii ABSTRACT A two-week cruise in the Eastern Gulf of Mexico using continuous profile recording salinity/temperature/depth (STD) equipment as the primary means for acquiring in situ data provides the basis for an examination of the water masses and circulation features present dur- ing August, 1966. Attention is focused on the upper 300 meters. Caribbean waters flowing in through the Yucatan Strait interact with resident Gulf of Mexico waters to create a dumb-bell shaped circulation pattern in the deeper waters of the Eastern Gulf. A large, well-developed, anticyclonic Northern Loop centered near 26° N. , 88° W. dominates the circulation. An elongated anticyclonic smaller loop extends north-northwestward from the western tip of Cuba (Cuban Loop) . The water masses in these circulation patterns are delineated into three distinct kinds based on significant character- istic temperature versus salinity relationship differences in the upper 300 meters. The Eastern Gulf Loop waters are categorized as Right-Hand (of the loop flow) and Left -Hand waters. The former is practically identical to the inflowing Yucatan Current waters. While the char- acteristic water mass of the western Gulf of Mexico is similar to the Left-Hand waters, there are sufficiently distinctive differences to warrant its classification as a unique intermediate water mass be- tween the Right-Hand and Left-Hand waters. The adaptability and performance evaluation of the STD equipment in quasi-synoptic oceanographic surveying is also presented. iv ACKNOWLEDGMENTS I am indebted to Dr. Dale F. Leipper for his academic and professional guidance in the preparation of this thesis and for his enthusiasm and personal interest during my tenure in this scholastic atmosphere. The method of treatment of the Gulf of Mexico waters contained herein is his suggestion, without which the completion of this paper would still be forthcoming. I am grateful also to unknown personnel of the United States Navy who dictated my presence at Texas A&M University; without their decision I would yet be blindly seeing my professional habitat. My most profound thanks, however, are directed to my family. Their patience and understanding made the arduous hours spent away from them pass quickly. TABLE OF CONTENTS Page ABSTRACT iii ACKNOWLEDGMENTS iv LIST OF TABLES vii LIST OF FIGURES viii LIST OF SYMBOLS AND ABBREVIATIONS xii CHAPTER I. Introduction 1 A. Historical Remarks 1 B. Present Status of Knowledge 2 C. Objectives 3 II. Observation 4 A. Background 4 B. Cruise Execution 4 C. Data Collection 5 D. Measurements 10 III. Presentation and Analysis of Data 11 A . Terminology 11 B. Characteristic Temperature-Salinity Relationships. 12 1. Right-Hand Eastern Gulf Loop Waters 12 2. Left-Hand Eastern Gulf Loop Waters 17 3. Western Gulf and Campeche Bank Waters 26 4. General 28 C. Surface Temperatures and Salinities 31 vx CHAPTER Page D. Temperature, Salinity, and Sigma-t in the Vertical Sections 34 •E. Currents and Transports 72 IV. Conclusions and Recommendations 101 A. Conclusions 101 B . Recommendations 104 APPENDIX A. STD System Performance Evaluation 107 1. System Description 107 2. Factors Affecting Performance 112 3. Data Reduction 113 4 . Data Processing 115 5 . STD Error Analysis 115 APPENDIX B. Comments on STD Salinity Correction Program 118 APPENDIX C. STD Salinity Correction Program 122 REFERENCES 146 VX1 LIST OF TABLES Table No. Page I. Designation of Coincident Hydrocast-STD Stations... 8 II. Right-Hand Eastern Gulf Loop Waters 16 III. Left-Hand Eastern Gulf Loop Waters 20 IV. Western Gulf Waters 27 V. Volume Transports Within Cuban Loop and Northern Loop 89 VI. Relative Surface Current Velocities and Volume Transports Between Stations 93 VII. Comparison of Maximum Surface Current Velocities and Surface Current Velocities Over Right-Hand Water Core 99 A-I. HYTECH Model 9006 System Specifications 114 VX11 LIST OF FIGURES Figure Page 1. STD stations occupied during ALAMINOS 66-A-ll, 4-18 August 1966. Lines indicate ship's track 7 2. Characteristic temperature versus salinity relation- ship for Right-Hand Eastern Gulf Loop Water. Mean depths (in meters) of observation of temperature- salinity values shown (dots) are noted alongside curve 14 3. Characteristic temperature versus salinity relation- ship for Left -Hand Eastern Gulf Loop Water. Mean depths (in meters) of observation of temperature- salinity values shown (dots) are noted alongside curve 19 4. Characteristic temperature versus salinity relation- ship for Western Gulf of Mexico Water. Mean depths (in meters) of observation of temperature-salinity values shown (dots) are noted alongside curve 23 5. Superimposed characteristic temperature versus salin- ity relationships for Right-Hand, Left-Hand, and Western Gulf Waters for temperature above 15° C. (upper 300 meters , approximately) 25 6. Temperature versus salinity values for Campeche Bank Waters. Dots represent observation points 30 7. Observed surface values of temperature versus salin- ity for selected stations, ALAMINOS 66-A-ll, 4-18 August 1966. Open circles are Left-Hand Water stations; dots are Right-Hand Water stations. Num- bers indicate STD stations. For station locations, see Figure 1 33 8. Transects of several course legs of ALAMINOS 66-A-ll, 4-18 August 1966. Vertical sections discussed in text correspond to these transects. See Figure 1 for correspondence of transects with station loca- tions 36 9. Temperature (degrees Celsius) along Transect A-A' , 7-8 August 1966, ALAMINOS 66-A-ll. Dots represent standard depth sampling levels. Vertical exagger- ation 3708:1 39 ix Figure Page 10. Salinity (parts per mille) along Transect A-A', 7-8 August 1966, ALAMINOS 66-A-ll. Dots represent standard depth sampling levels. Vertical exag- geration 3708:1 41 11. Sigma-t along Transect A-A', 7-8 August 1966, ALAMINOS 66-A-ll. Dots represent standard depth sampling levels. Vertical exaggeration 3708:1 43 12. Temperature (degrees Celsius) along Transect B-B- , 8-9 August 1966, ALAMINOS 66-A-ll. Dots represent standard depth sampling levels. Vertical exaggera- tion 371:1 45 13. Salinity (parts per mille) along Transect B-B' , 8-9 August 1966, ALAMINOS 66-A-ll. Dots represent standard depth sampling levels. Vertical exaggera- tion 371:1 47 14. Sigma-t along Transect B-B', 8-9 August 1966, ALAMINOS 66-A-ll. Dots represent standard depth sampling levels. Vertical exaggeration 371:1 49 15. Temperature (degrees Celsius) along Transect C-C ' , 9-10 August 1966, ALAMINOS 66-A-ll. Dots represent standard depth sampling levels. Vertical exaggera- tion 371:1 53 16. Salinity (parts per mille) along Transect C-C, 9-10 August 1966, ALAMINOS 66-A-ll. Dots represent stan- dard depth sampling levels. Vertical exaggeration 371:1 55 17. Sigma-t along Transect C-C, 9-10 August 1966, ALAMINOS 66-A-ll. Dots represent standard depth sampling levels. Vertical exaggeration 371:1 57 18. Temperature (degrees Celsius) along Transect D-D' , 10-12 August 1966, ALAMINOS 66-A-ll. Dots represent standard depth sampling levels. Vertical exaggera- tion 371:1 60 19. Salinity (parts per mille) along Transect D-D' , 10- 12 August 1966, ALAMINOS 66-A-ll. Dots represent standard depth sampling levels. Vertical exaggera- tion 371:1 62 Figure Page 20. Sigma-t along Transect D-D', 10-12 August 1966, ALAMINOS 66-A-ll. Dots represent standard depth sampling levels. Vertical exaggeration 371:1 64 21. Temperature (degrees Celsius) along Transect E-E' , 16-18 August 1966, ALAMINOS 66-A-ll. Dots represent standard depth sampling levels. Vertical exaggera- tion 371:1 67 22. Salinity (parts per mille) along Transect E-E? , 16- 18 August 1966, ALAMINOS 66-A-ll. Dots represent standard depth sampling levels. Vertical exaggera- tion 371:1 69 23. Sigma-t along Transect E-E', 16-18 August 1966, ALAMINOS 66-A-ll. Dots represent standard depth sampling levels. Vertical exaggeration 371:1 71 24. Dynamic topography of the surface relative to the 1000-db surface, ALAMINOS 66-A-ll, 4-18 August 1966. Contour interval, 0.1 dynamic meters. Dots represent STD station locations. See Figure 1 for identification of stations 75 25. Dynamic topography of the surface relative to the 300-db surface, ALAMINOS 66-A-ll, 4-18 August 1966. Contour interval, 0.1 dynamic meters. Dots repre- sent STD station locations. See Figure 1 for identification of stations 77 26. Topography of the 22° C. isothermal surface. Con- tour interval 50 meters 79 27. Profiles of the sea surface from dynamic computa- tions, Stations 31-51, 8-11 August 1966, ALAMINOS 66-A-ll 81 28. Profiles of the sea surface from dynamic computa- tions, Stations 51-65, 11-13 August 1966, ALAMINOS 66-A-ll 83 29. Profiles of the sea surface from dynamic computa- tions, Stations 65-83, 13-16 August 1966, ALAMINOS 66-A-ll 85 30. Profiles of the sea surface from dynamic computa- tions, Stations 83-95, 16-18 August 1966, ALAMINOS 66-A-ll 87 XI Figure Page 31 Sample Salinity/Temperature/Depth (STD) analog record. Grid resolution of graph paper indicated in upper left corner. Salinity, temperature, and depth scales shown (used throughout AL AMINOS 66- A-ll) may be changed for larger-scale recording of the in situ water structure. This particular analog record was observed at Station 88 (see Figure 1) . Illustration is approximately two- thirds recorded size 109 xii LIST OF SYMBOLS AND ABBREVIATIONS A, B, C Empirical coefficients in relation of conductivity as a function of temperature. cm/sec Velocity measure, centimeters per second. D Geopotential (dynamic height) anomaly (dynamic meters) . db Pressure measure, decibars. dyn. m. Dynamic meters. G Conductivity. h Vertical separation between temperature and salinity probes of STD sensor unit. K Conductivity coefficient. K_ Conductivity ratio coefficient. km. Linear measure, kilometers (1 kilometer = 0.538 nautical miles) . kts. Velocity measure, nautical miles per hour (1 kt . = 51.5 cm/sec) . m. Linear measure, meter(s). 3 m /sec Volume transport measure, cubic meters per second. n.m. Linear measure, nautical miles (1 n.m. = 1853 m.). Q Transport function for geopotential volume flow. R Conductivity ratio. S Salinity (°/oo) . S* Uncorrected or indicated salinity from STD salinity sensor (°/oo) . SAIW Subantarctic Intermediate Water. STD Salinity/Temperature/Depth continuous in situ recording equipment . SUW Subtropical Underwater. Xlll T Temperature (° C). V STD sensor unit descent rate (meters per second) . Z Vertical coordinate (meters or decibars) . a, 3, 6 Empirical coefficients in relation for conductivity ratio as a function of salinity. a Sigma-t, density parameter; a function of salinity and temperature as related to atmospheric pressure. ° C. Degrees Celsius (degrees Centigrade) . % Percent . /oo Parts per thousand; parts per mille. N. Degrees of North latitude. W. Degrees of West longitude. Minutes (arc measure) of latitude and longitude. o o o CHAPTER I INTRODUCTION A. Historical Remarks An hydrographic analysis of Gulf of Mexico waters was conducted by Parr in the late 1930' s, and his conclusions (1935a, b; 1937a, b; 1938) were until recently (Wennekens, 1959) the only detailed study of the temperature and salinity structure of Gulf waters. Parr's oceanographic data, however, were meager, as there were few deep water measurements obtained (Leipper, 1954). Dietrich (1939) subsequently described in his classical survey of the American Mediterranean the presence of an Eastern Gulf clock- wise loop current, formed by the meandering of the Yucatan Current as it progressed from the Caribbean Basin to the Straits of Florida. Dietrich's chart of surface current patterns was based on a descrip- tion (by Bjerknes) of movements of American shipping in the Gulf in 1905 and 1906 and of English shipping for the Caribbean area, and on American pilot charts. Although the circulation pattern depicted was deduced from the study of surface measurements in the Gulf, and in- cludes wind-driven effects, it was taken to be representative of the general circulation within the surface layers. A large, well-defined anticyclonic surface loop was observed in the Eastern Gulf on three cruises conducted during 1951-1952 by the Texas A&M Research Foundation and the United States Fish and Wildlife Service. These cruises provided the first partial coverage of the Gulf with information needed to compute deep water currents; subse- quent analysis revealed that the deep water data supported the general surface circulation pattern described by Parr and Dietrich (Leipper, 1954). A 1954 summer cruise was conducted (by the Texas A&M Research Foundation) specifically to study the loop current. That cruise (Austin, 1955) supplied descriptive hydrographic data, including dynamic height analyses and temperature-depth and oxygen- depth profiles across the loop, clearly depicting its presence. Austin concluded that the loop was a common feature of the Yucatan Current -Gulf Stream system, that it was centered at approximately 26° N. , 86° W. (at the time of his summer cruise) , and that it varied in size, shape, and intensity in time and space. B. Present Status of Knowledge Observation of time and space variability of the loop since 1954 has been recorded in several winter and summer cruises in the Eastern Gulf (McLellan, 1960; Gaul, 1967; Leipper, 1967; Nowlin and McLellan, 1967) and adjacent waters (Cochrane, 1961, 1962, 1963, 1965, 1966). Wust's work (1964) is an exacting analysis of the Caribbean source waters of the Eastern Gulf, while Cochrane' s investigations of the Yucatan Current offer a description of this water at its point of introduction into the Gulf basin. Nowlin and McLellan (1967) have presented their results from a rapid winter survey of the entire Gulf of Mexico in 1962; their attention is focused on the circulation regions of the Eastern and Western Gulf sections, and considerable discussion is devoted to the Eastern Gulf Loop Current system. Thus, while considerable hydrographic data is presently avail- able for an objective analysis of the shallow layers of the loop waters, no treatments of water mass description primarily directed at the upper 300 meters of these waters have been made. C. Objectives An August, 1966 cruise in the Eastern Gulf of Mexico is investi- gated in order to describe on a synoptic basis the temperature, salinity, and density characteristics of the surface waters (upper 300 meters) located over the deeper portions of the Eastern Gulf basin; to define the water masses present in the Eastern Gulf Loop flow based on characteristic temperature versus salinity relation- ships in the upper 300 meters; to determine to what extent the presence of these water masses may be indicated by sea surface tem- perature and/or salinity alone; and to analyze the effectiveness of the salinity/temperature/depth (STD) continuous profile recording equipment as a primary means of oceanographic data collection. CHAPTER II OBSERVATION A. Background The Eastern Gulf waters, in general, have been surveyed several times, as referenced previously; most of the resulting studies were directed toward the Gulf circulation and dynamics (especially for the deeper waters) or were a composite compilation of data from several cruises over a period of several years. A quasi-synoptic approach, such as that of Nowlin and McLellan (1967), permits a more meaningful interpretation of specific characteristic features of the Eastern Gulf and its loop current system; however, there was but one early cruise (Austin, 1955) approaching a near-synoptic representation of condi- tions in the late summer season -.- the season during which the East Gulf loop has its maximum intrusion into the Gulf, at least in certain years (Leipper, 1967) . Any analysis which is dependent upon the com- bination of data from various years and seasons is certain to be mis- leading, especially in the surface layers, since Gulf currents show great variation in position. With these thoughts foremost, an analysis of a recent late summer cruise (ALAMINOS 66-A-ll, August 4-18, 1966, conducted by Dr. D. F. Leipper) was undertaken. The author participated in this cruise. B. Cruise Execution Pre-cruise planning for ALAMINOS 66-A-ll was significant in that station locations were not predetermined; rather, the objective of the cruise was to seek, find, and investigate as thoroughly as poss- ible within the limited ship time available the Eastern Gulf Loop Current. 66-A-ll accomplished its mission. The final cruise track (Figure 1) suggests the thoroughness with which the current was traced. It should be noted that the elapsed time of the significant data gathering period was less than two weeks, a fact which lends credence to synoptic treatment of the assembled data. C. Data Collection Cruise 66-A-ll was unique in that a Hytech Model 9006 salinity/ temperature/depth continuous profile recorder (STD) was utilized for collecting nearly all in situ salinity and temperature data for the cruise. Discussion of the instrument's utility and performance eval- uation is given in Appendix A. Classical hydrocasts (using Nansen bottles with reversing thermometers) were made during the initial course leg of the cruise (see Fig. 1) and at several subsequent lo- cations (Table I) ; their data were used primarily as "reference" values of temperature and salinity, at selected depths, to which the STD analog trace (paper graph) and digital (punched tape) outputs were compared for immediate "on station" performance evaluation and subsequent error analysis. Hourly and "on station" bathythermograph casts and observations of surface temperature and salinity provided supplemental information for comparison with the STD measurements. FIGURE 1. STD stations occupied during ALAMINOS 66-A-ll , 4-18 August 1966. Lines indicate ship's track. TABLE I DESIGNATION OF COINCIDENT HYDROCAST - STD STATIONS CRUISE ALAMINOS 66-A-ll AUGUST 4-18, 1966 Station Sampling Depths, Meters 1** 0, 15, 25, 50, 75, 100, 125, 150, 175 2 0-1002 (Deep Cast Sample Levels***) 3 0-996 (Deep Cast Sample Levels***) 4 0-1000 (Deep Cast Sample Levels***) 5 0-1198 (Deep Cast Sample Levels***) 6 0, 50, 75, 125, 175, 300 7 0-1199 (Deep Cast Sample Levels***) 8 0-1187 (Deep Cast Sample Levels***) 9 0-1198 (Deep Cast Sample Levels***) 10 0-800 (Deep Cast Sample Levels***) 15* 22 16* 23 53* 15, 399, 802, 1199 54* 15, 408, 760, 1171 55 0-1201 (Deep Cast Sample Levels***) 56* 15, 410, 778, 1180 57* 15, 465 59* 8, 453 61* 25, 406 TABLE I (continued) DESIGNATION OF COINCIDENT HYDROCAST - STD STATIONS CRUISE ALAMINOS 66-A-ll AUGUST 4-18, 1966 Station Sampling Depths, Meters 62* 790 63* 810 65* 600 66* 400 68* 190 75* 1196 78* 949 81* 400 ** No STD Cast * Nansen Bottles Attached to STD Cable *** Deep Cast Sample Levels: 0, 50, 100, 150, 200, 300, 400, 500, 600, 800, 1000, 1200. 10 "Surface" temperature and salinity observations were made by direct sampling at a nominal depth of one meter below the air-sea interface to prevent the distortion of this data by the influence of short-term variations, viz. , wind- influenced property transfer processes. Observations of oxygen and phosphate concentrations of the water masses were not made. Attachment of sampling bottles to the STD cable at each station would have virtually doubled station occupancy time and would have further limited the coverage of the Eastern Gulf Loop Current waters within the alloted time period. D. Measurements Salinity (chlorinity) determinations of all water samples were conducted as soon as possible after collection, utilizing a ship- board conductive salinometer built at the University of Washington. Temperatures and sampling depth levels of the Nansen bottle hydrocasts were determined following standard oceanographic data processing techniques (LaFond, 1951). Accuracy of these measurements can be shown to be within the established limits, i.e. , + 0.02 parts per mille in salinity, + 0.02° C. in temperature, and + 5 meters in depth (Sverdrup et .al. , 1942) . The prima facie acceptance of the values of these measure- ments is of paramount importance to the correction of STD measure- ments and subsequent interpretation of dynamic computations and graphical analyses based on STD data (see Appendix A.). 11 CHAPTER III PRESENTATION AND ANALYSIS OF DATA A. Terminology The Eastern Gulf Loop Current is directly caused and maintained by the influx of the Yucatan Current into the Gulf of Mexico via the Yucatan Strait. The representative temperature versus salinity re- lationship of the Right-Hand portion of this inflowing Yucatan Cur- rent is given by Wust (1964: Fig. 3); a distinctive feature is the subsurface salinity maximum near 22.5° C. and 36.75°/oo (Subtropical Underwater - SUW) . Wennekens (1959: Fig. 3A) also terms this water "Yucatan Water" and likewise illustrates the salinity maximum feature at a depth of about 200 meters. The nomenclature of Nowlin and McLellan (1967) is herein adopted for designation of such water with- in the confines of the Gulf of Mexico basin: Eastern Gulf Loop water. This water mass remains remarkably uniform during its tra- verse through the Gulf; so much so, in fact, that the "core" of Sub- tropical Underwater remnant of the Yucatan Current may be used as an index of its location. The surrounding waters of the Gulf are modi- fied in varying degrees dependent upon the intensification or de- gradation of the inflow and the extent of development of the Loop northward into the Gulf; however, a subsurface salinity maximum of approximately 36.4°/oo determines the demarcation between distinc- tive Eastern Gulf Loop waters and other Gulf of Mexico waters. It must be emphasized at this point that the data presented 12 herein and inferences and subsequent conclusions based thereon are considered to be representative only of conditions in the Gulf of Mexico during early August, 1966, unless otherwise specified. Subsequent discussion of salinity, temperature, density, and related water mass properties involves delineation of "Right-Hand" or "Left-Hand" categorization of the waters at each station. Right- Hand waters exhibit a temperature-salinity correlation commensurate with the typical Yucatan Current T-S curve, and such waters are rep- resentative of the right side of the flow around the loop, facing downstream. Left-Hand waters exhibit a distinctively different T-S correlation which defines these waters above 300 meters and is indic- ative of the left side of the loop flow, facing downstream. The above nomenclature serves well to quickly separate the waters at the various stations into two major groupings useful in the study of the location of the current. Further, the resemblance of this terminology to Stommel's de- scription (1965, p. 21) of the Gulf Stream is not coincidental: "The Gulf Stream is not a river of hot water flowing through the ocean, but a narrow ribbon of high- velocity water acting as a boundary that prevents the warm water on the Sargasso Sea (right-hand) side from over-flowing the colder, denser waters on the inshore (left-hand) side." B. Characteristic T-S Relationships 1. Right-Hand Eastern Gulf Loop Waters. Figure 2 shows the composite temperature versus salinity relationship for all ALAMINOS 66-A-ll stations exhibiting water mass properties typical of the 13 FIGURE 2. Characteristic temperature versus salinity relationship for Right-Hand Eastern Gulf Loop Water. Mean depths (in meters) of observation of temperature-salinity values shown (dots) are noted alongside curve. 14 (•%) A1INHVS 15 Right-Hand waters of the Eastern Gulf Loop Current. Table II sum- marizes the mean values of this composite T-S relationship at standard depth levels. (Reference to standard depths in this paper signifies sampling levels of 0, 10, 20, 30, 50, 75, 100, 125, 150, 200, 250, 300, 400, 500, 600, 700, 800, 1000, and 1200 meters, unless otherwise specified.) The T-S relationship for Right-Hand waters is practically ident- ical to the characteristic T-S relationship for the Caribbean Basin waters as shown by Wust (1964: Fig. 3). The salinity minimum of 34.88°/oo at 6.1°C. is clearly related to the remnant of Sub-Antarctic Intermediate Water (SAIW) , which has nominal values in the Caribbean of 34.75°/oo at 6.3° C. A maximum subsurface salinity value of 36.74°/oo at 21.2° C. is likewise practically coincident with the Sub- tropical Underwater (SUW) of Wust ' s Caribbean T-S curve. Above 22°C, however, the Right-Hand waters exhibit a marked departure from the Caribbean Basin T-S curve. The shape of the Right-Hand water T-S curve from 21° C. to 24° C. is the mirror image of the curve from 21° C. to about 18° C. ; the temperature extremities of this segment are coincident with the 36.4°/oo isohaline. Near 25° C. the curve reverses slope to represent the relatively uniform salinity (approx- imately 35.9-36.0°/oo from 28-29° C.) of the surface layers (upper 50 meters) typical of late summer-early fall conditions in the Gulf of Mexico. Note the perpendicularity of the curve to the isopyncnals at 26° C. The portion of the curve from 5° C. to about 17° C. coincides 16 TABLE II RIGHT-HAND EASTERN GULF LOOP WATERS CRUISE ALAMINOS 66-A-ll AUGUST 4-18, 1966 Depth, Meters Temperature, C. Salinity, 0/00 Sigma-t 0 29.2 35.86 22.6 10 29.2 35.86 22.7 20 29.2 35.92 22.7 30 29.0 36.04 22.9 50 28.5 36.07 23.1 75 27.6 36.15 23.4 100 26.7 36.13 23.7 125 25.7 36.19 24.1 150 25.2 36.28 24.3 200 24.1 36.52 24.8 250 21.5 36.68 25.7 300 19.4 36.60 26.2 400 17.4 36.37 26.5 500 15.4 36.06 26.7 600 12.6 35.60 27.0 700 10.3 35.27 27.1 800 8.7 35.03 27.2 1000 6.6 34.89 27.4 1200 5^ 34.90 27.6 Stations From Which The Above Data Were Compiled: 30, 31, 32, 33, 34, 35, 41, 42, 43, 44, 45, 46, 47, 48, 49, 54, 55, 56, 69, 70, 71, 79, 80, 81, 85, 86, 87, 88, 89, 90. (For locations of stations, refer to Figure 1) 17 with the usual T-S configuration for the Gulf basin waters. Above 17° C. the significant features described above distinguish this Right-Hand water from its source Yucatan (Caribbean Basin) water. The nominal depth of the subsurface salinity maximum is about 200 meters; Wennekens (1959) also has found 200 meters to be the approximate location of the salinity maximum (SUW remnant) . Nowlin and McLellan (1967) specify a depth of 150 meters. Wenneken's data cover the summer season, while Nowlin and McLellan' s data is repre- sentative of winter conditions in the Gulf. In winter, these waters, existing as an elongated loop northwest of Cuba (Nowlin and McLellan, 1967) , are located over the moderately deep waters of the southeastern basin of the Eastern Gulf; the entering Yucatan waters move swiftly around the loop and exit the Florida Straits without expanding in breadth and depth. Conversely, in summer- fall, the Loop extends well northward over the deeper waters of the central basin of the Eastern Gulf (Leipper, 1967) . 2. Left-Hand Eastern Gulf Loop Waters. Figure 3 shows the com- posite temperature versus salinity relationship for the ALAMINOS 66-A-ll stations exhibiting water mass properties typical of the Left- Hand waters of the Eastern Gulf Loop Current. Table III summarizes the mean values of the composite T-S relationship at standard depths. The T-S relationship for Left-Hand waters is coincident with the T-S relationship for the Right-Hand waters in the temperature range from 5° C. to about 17° C. In this temperature range, the waters of the Eastern Gulf Loop Current are very similar. (Compare Figs. 2 18 FIGURE 3. Characteristic temperature versus salinity relationship for Left-Hand Eastern Gulf Loop Water. Mean depths (in meters) of observation of temperature-salinity values shown (dots) are noted alongside curve. 19 (°%) A1INHVS 10 fO 5 IO in io (0 IO O 1 1 1 1 1 lO 1 1 l i I l 1 1 1 1 1 1 1 1 oV. • ml • A" •' — \ IO \ • • CM ••o\"- ', m\ • \ • CM •cvjI . — ^j — U 2^ Of. — UJ 3 o /. in X cvyt — £ «o O '"jF < _ 20 TABLE III LEFT-HAND EASTERN GULF LOOP WATERS CRUISE ALAMINOS 66-A-ll AUGUST 4-18, 1966 Depth, Meters Temperature, °C. Salinity, 0/00 Sigma-t 0 29.2 35.71 22.5 10 29.1 35.73 22.6 20 29.0 35.77 22.7 30 28.0 35.86 23.1 50 24.6 36.15 24.3 75 23.9 36.26 24.9 100 20.4 36.39 25.7 125 19.0 36.42 26.1 150 18.1 36.38 26.3 200 15.9 36.17 26.5 250 15.3 36.08 26.7 300 14.2 35.88 26.8 400 11.1 35.36 27.0 500 8.7 ' 35.06 27.2 600 8.1 34.99 27.3 700 6.4 34.88 27.4 800 5.6 34.88 27.5 1000 5.0 34.93 27.6 1200 4^7 34.96 27.7 Stations From Which The Above Data Were Compiled: 28, 29, 36, 37, 40, 50, 53, 57, 58, 59, 64, 66, 67, 72, 73, 74, 75, 76, 82, 84, 91, 92, 93, 94. (For locations of stations, refer to Figure 1) 21 and 3.) In Left -Hand waters the Subtropical Underwater influence is evident to a slight degree, near 19.5° C. , where the subsurface salinity maximum of approximately 36.4°/oo is reached. It is pos- sible that the SUW remnant of the Right-Hand waters has diffused into other Gulf waters along the isopyncnal surfaces to form this most characteristic feature of the Left-Hand waters. Left-Hand waters nearer the surface are characterized by sig- nificantly lower salinities (35 ,6-35.9°/oo) than exhibited in the Western Gulf T-S curve (36 . 2-36 ,4°/oo) and the Right-Hand T-S curve. (Compare Figures 2, 3, and 4.) From about 16.5° C. , corresponding to a nominal depth of nearly 200 meters, to 27° C, at approximately 35 meters depth, these lower salinities of the Left-Hand waters may mix with the higher salinity SUW remnant of the Right-Hand waters to form the intermediate water mass of the Western Gulf (see Fig. 5). The significant distinction between Left-Hand and Western Gulf waters lies in the temperature range from 20-26° C. While both waters have salinities near 36.4°/oo at 20° C. , Left-Hand water salinities decrease markedly as temperature increases, yet the West- ern Gulf T-S curve is relatively flat (constant salinity) over the same temperature span. One remarkable distinction between Left-Hand and Right-Hand waters is in the depths at which given values of the water mass properties are found. In all instances (except in the mixed layer) the properties of the Left-Hand waters are elevated above those of 22 FIGURE 4. Characteristic temperature versus salinity relationship for Western Gulf of Mexico Water. Mean depths (in meters) of observation of temperature-salinity values shown (dots) are noted alongside curve. 23 (°%) A1INHVS 24 FIGURE 5. Superimposed characteristic temperature versus salinity relationships for Right-Hand, Left-Hand, and Western Gulf Waters for temperatures above 15° C. (upper 300 meters, approximately) . 25 (°%) A1INHVS 26 equal magnitude in the Right-Hand waters, i.e. , the depth at which a given value of any mass property of the Left-Hand water is found is less than the depth at which the same value appears in Right-Hand water. For example, the differences in the depths at which equal values of sigma-t are found varies from 20 meters (at 28° C.) to 250 meters (at 16° C). Further, the depths of the minimum salinity of the Left-Hand waters is some 300 meters shallower than its location in Right-Hand waters. Tables II and III facilitate comparison of the depths of other properties. 3. Western Gulf and Campeche Bank Waters. Stations 2 - 11, all west of 89° W. longitude, have characteristic T-S relationships as illustrated in Figure 4. Table IV tabulates the mean values of tem- perature and salinity at standard depths for these Western Gulf waters. This T-S curve is not unlike that for Western Gulf waters given by Wennekens (1959: Fig. 3B) . The temperature range of the upper 100 meters varies from 20- 29° C., while the salinity (approximately 36.5°/oo) remains almost unchanged from 40-100 meters. Salinities decrease gradually from a surface value of about 36.5°/oo to a near-surface minimum of about 36.2°/oo at a depth of about 30 meters. Below this depth the salinity increases to a maximum subsurface value of 36.48°/oo at about 50 meters depth. The high salinities in the upper 50 meters are at- tributed to increased seasonal evaporation and convective mixing of these waters in the Western Gulf. The unorganized T-S data points (Figure 6) of the Campeche Bank 27 TABLE IV WESTERN GULF WATERS CRUISE ALAMINOS 66-A-ll AUGUST 4-18, 1966 Depth, Meters Temperature, °C. Salinity, 0/00 Sigma-t 0 30.0 36.55 22.9 10 29.7 36.44 23.0 20 29.3 36.34 23.1 30 28.5 36.29 23.4 50 23.8 36.49 24.8 75 22.0 36.48 25.6 100 20.2 36.46 26.0 125 19.1 36.41 26.3 150 17.6 36.29 26.5 200 15.4 36.04 26.8 250 13.2 35.65 26.9 300 11.9 35.45 27.0 Stations From Which The Above Data Were Compiled: 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 51, 52, 65, 68, 78, 83, 95 (For locations of stations, refer to Figure 1) 28 stations (Stations 12-27) reveal no significant pattern; the congre- gation of several points near 36.1°/oo and 29° C. (surface values) may be associated with the seasonal evaporation and wind-stirring of these shallow shelf waters. 4. General. For the cruise of August, 1966, the T-S curve for a given station is readily classified as either Right-Hand or Left- Hand water using criteria and definitive temperature and salinity values presented above. Transition from one water mass to the other, when occurring, is accomplished between only a few stations. (Average distance between stations on this cruise was 30 n.m.) Even though the marked depth differences in the properties of these two water masses are not apparent in their characteristic T-S curves, use of the T-S relationship alone is a practical means of determining the boundaries of the Eastern Gulf Loop Current. Wennekens (1959) defines the water mass in the shallow Eastern Gulf as "Continental Edge Water". It has a T-S relationship similar to the Left -Hand Eastern Gulf waters defined above. He notes "the great reduction of the salinity maximum..." in "... the upper portion of the curve ..." having "... salinities ranging between 36.1°/oo and 36.6°/oo". The summer temperature range of the Edge Water was found to be from 30° C. (at the surface) to 20° C. (at 100 meters). He concluded that the "differentiation between the Edge Water and Yucatan Water is found mainly in the upper 300 m. Below about 300 m., both (have) T-S characteristics (which) merge within a single narrow en- velope". 29 FIGURE 6. Temperature versus salinity values for Campeche Bank Waters. Dots represent observation points. 30 (°%) A1INHVS 31 For this August cruise, the differences in the magnitudes of the subsurface salinity maxima between the Right-Hand and Left-Hand waters are even more significant than the differences between Wennekens ' Yucatan and Continental Edge waters. (See especially Wennekens, 1959: Fig. 4.) While Wennekens categorizes his Edge Water as the intermed- iate water mass between Yucatan Water and Western Gulf water (a water mass unmodified by the Yucatan Water and resident west of a line con- necting the Mississippi delta and the Yucatan Peninsula) , it would appear that, based on the findings of this cruise, the Western Gulf waters are the intermediate water mass possibly formed by the combi- nation of the Right-Hand and Left-Hand water mass properties. C. Surface Temperatures and Salinities An attempt was made to determine the presence of the Right-Hand and Left-Hand waters of the Eastern Gulf Loop Current based on the observed surface temperature and salinity values. On the premise that the warm, high-salinity core of the Right-Hand waters would be evident in relatively warmer temperatures and higher salinities at the sur- face, while the Left-Hand waters would not be so significantly repre- sented by their surface values of temperature and salinity, a simple plot of surface salinity versus temperature was prepared (Figure 7) . Nearly all Right-Hand waters fell within the ranges of 35. 77-36 .0°/oo and 29-29.8° C. , while the majority of Left-Hand waters were outside these ranges. However, there were sufficient stations of definite Left-Hand water characteristics plotting within the range of Right- 32 FIGURE 7. Observed surface values of temperature versus salinity for selected stations, ALAMINOS 66-A-ll, 4-18 August, 1966. Open circles are Left-Hand Water stations; dots are Right-Hand Water stations. Numbers indicate STD stations. For station locations, see Figure 1. 33 (°%) O lO ro O CO lO ro O 0) lO ro A1INI1VS § 2 O CM O ro co co ro ro CO ro CO ro 1 1 1 1 1 1 1 1 1 1 r-° O O) CD 0 CO 0 rO UJ in fO (J) O r- 00 cr o ^o o* F o r>- o 3 UJ Q_ 00 • m 00 • 00 5 CD o — O Ld r^ CT> Is- co CJ h- O t\J o • o ir: in • Tj-CD mm • • in ^f CD 00 o • o ro • in o o — O • • ro CJ m 00 CJ o ro in 65 o o • o o 1 1 1 1 1 1 1 1 1 1 34 Hand waters to cast doubt on judgments based on the limiting values stated above. In fact, there were a few stations representing West- ern Gulf waters which also fell within the Right-Hand water limits! The explanation of these paradoxical results lies in the seasonal depth of the mixed layer. Of at least 30 meters depth, and often deeper, as observed at the time of this cruise, the late summer mixed layer effectively masks the temperature and salinity structure of the underlying waters. The Left-Hand waters are practically indis- tinguishable from the closely-related Western Gulf waters in the analysis of their surface temperature and salinity values. Surface values of temperature and salinity falling within the ranges deter- mined for the period of this cruise can be termed as only suggestive of Right-Hand waters beneath. D. Temperature, Salinity, and Sigma-t in the Vertical Sections The temperature, salinity, and sigma-t profiles in the vertical sections for several cross-current legs are presented as Figures 9 through 23. Figure 8 shows the transects approximating these cross- current legs for this cruise. These vertical sections represent the most significant portrayal of the Eastern Gulf Loop Waters and have been selected (based on specific features particularly relevant to the description of the Right-Hand and Left-Hand waters) from all such sections prepared from the data for this August cruise. In the following discussion, inference of currents in the upper 1000 meters based on temperature and salinity (and hence density) 35 FIGURE 8. Transects of several course legs of ALAMINOS 66-A-ll, 4-18 August 1966. Vertical sections discussed in text corre- spond to these transects. See Figure 1 for correspondence of transects with station locations. 36 37 distributions in the vertical sections is predicated on the assump- tion that such currents are geostrophic and are relative to an, assumed level of no motion at some greater depth. Briefly, the direction of such currents relative to two areas of different tem- perature (density) is such that with warmer, less dense water on the right, the flow is directed into the vertical section. Figures 9, 10, and 11, depicting the transect A-A' across the Campeche Bank (see also Fig. 1), reveal two interesting phenomena. At St. 22, about 50 n.m. (93 km.) west of the eastern edge of the Campeche Bank, an uplifting of relatively cooler water is evidenced which can rationally be attributed to the presence of the inflowing Yucatan Current not over 75 n.m. (139 km.) to the east. As the Yuca- tan Current approaches the narrow Yucatan Strait, the colder waters which have been traversing the Caribbean Basin at considerable depths (Wust, 1964sPlate XIX) are lifted into the shallower depths due to the restrictions imposed on the flow by the bathymetry. The prevail- ing winds (easterly) also tend to pile up the surface waters at the entrance to the channel. As the sill depth of the Yucatan Strait is estimated at about 1600 meters (Sverdrup et . al. , 1942), the piling up effect of the colder, deeper waters at the sill results in some spillover into the Yucatan Strait. Additionally, the superposition of the swiftly flowing Yucatan Current aids in moving this colder water northward along the Strait, with the result that cold, low- salinity waters are lifted up the slopes of the Yucatan Strait. (See Figures 12, 13, and 14, Transect B-B' , for the area just east of the 38 FIGURE 9. Temperature (degrees Celsius) along Transect A-A' , 7-8 August 1966, ALAMINOS 66-A-ll. Dots represent standard depth sampling levels. Vertical exaggeration 3708:1. 39 O < I- (SH313IN) Hld3Q 40 FIGURE 10. Salinity (parts per mille) along Transect A-A' , 7-8 August 1966, ALAMINOS 66-A-ll. Dots represent standard depth sampling levels. Vertical exaggeration 3708:1. 41 (SU313W) H±d3Q < 42 FIGURE 11. Sigraa-t along Transect A-A' , 7-8 August 1966, ALAMINOS 66-A-ll. Dots represent standard depth sampling levels, Vertical exaggeration 3708:1. 43 (SU313IAI) Hld3d 44 FIGURE 12. Temperature (degrees Celsius) along Transect B-B', 8-9 August 1966, ALAMINOS 66-A-ll. Dots represent standard depth sampling levels. Vertical exaggeration 371:1. 45 50 100 DISTANCE (N.M.) FIGURE 12 46 FIGURE 13. Salinity (parts per mille) along Transect B-B' , 8-9 August 1966, AL AMINOS 66-A-ll. Dots represent standard depth sampling levels. Vertical exaggeration 371:1. 47 STATIONS 27 Onr 50 100 DISTANCE (N.M.) FIGURE 13 150 200 48 FIGURE 14. Sigma-t along Transect B-B' , 8-9 August 1966, ALAMINOS 66-A-ll . Dots represent standard depth sampling levels Vertical exaggeration 371:1. 49 STATIONS 27 0 50 100 DISTANCE (N.M.) FIGURE 14 50 Campeche Bank.) Some portions of this water eventually gain the precipice of the slope and spread horizontally over the bottom of the Campeche Bank, as they are no longer restricted to vertical uplift. Thus, at St. 22 there is evidence of the process described above. At St. 14, where a surface temperature of 28.6° C. was recorded, there is a suggestion of upwelling, though weak. While Cochrane (1966) reported the presence of upwelling over the Campeche Bank for several summer cruises, and particularly in May 1965, and further states that upwelling "... probably is active from March through Aug- ust," the vertical sections over the Campeche Bank for this August cruise do not show such upwelling. It is noted, however, that Cochrane' s transects cross the 100-fathom curve at several locations north of A-A' and are therefore closer to the Yucatan Current as it bends northwestward around that isobath. Transect B-B', extending across the Yuca^rtan Strait and thence to the Florida Shelf depicts (Figures 12, 13, and 14) the northern semi- circle of the Cuban Loop. The center of the loop, especially in the greater depths, is located at St. 32, with some skew toward the right (to the east) of the highest velocities (as indicated by the isoline gradients) as the surface is approached. The core of salinities higher than 36.6°/oo centered about St. 33, at a nominal depth of about 210 meters, is an excellent representation of Right-Hand waters; these Right-Hand waters are present in this loop out to the extent of the cell of salinities greater than 36.4°/oo, beyond which the waters are representative of Left -Hand water. Notice that the slopes of the 51 isolines in the eastern portion of this transect (the southeastward flowing Right-Hand Eastern Gulf Loop waters) are practically the same as those for the northward flowing Right -Hand water in the west- ern portion. More significant, however, is the parallelism of the isolines to the bottom of the section (1200 meters), indicating that the inflowing and outflowing currents decrease uniformly from the surface to the depths represented. Surface currents based on dynamic computations relative to the 300-db surface — above which depth the warm, high-salinity core of the Right-Hand waters is found — might then be reliably used to give an indication of the flow beneath the 300-db surface. (Specific currents and transports found on this cruise are discussed in the following section.) The "banded" structure of the Yucatan Current noted by Cochrane (1963, 1965, 1966) is not evident in this transect; however, it is possible that the current has united into a single flow (as depicted here) by the time it reaches this latitude (24° N.). The Yucatan Strait proper is some 100 n.m. (192 km.) upstream (to the south). Figures 15, 16, and 17 show the isoline structures for the east- ward flow out of the Gulf of Mexico (Transect C-C). Notice that the patterns of isolines are practically the same as observed in the eastern section of transect B-B'} indicating that there is very little modification of the outflowing waters in the short span be- tween those two transects. The concentrated flow between Sts. 40 and 42, as evidenced by the sharp change in gradient of the isolines south of the latter station, is located at approximately 24° N. , 84° 52 FIGURE 15. Temperature (degrees Celsius) along Transect C-C , 9-10 August 1966, ALAMINOS 66-A-ll. Dots represent standard depth sampling levels. Vertical exaggeration 371:1. 53 STATIONS 40 0 50 DISTANCE (N.M.) FIGURE 15 100 54 FIGURE 16. Salinity (parts per mille) along Transect C-C , 9-10 August 1966, ALAMINOS 66-A-ll. Dots represent standard depth sampling levels. Vertical exaggeration 371:1. 55 STATIONS 40 0 0 50 DISTANCE FIGURE 100 N.M.) 16 56 FIGURE 17. Sigma-t along Transect C-C* , 9-10 August 1966, ALAMINOS 66-A-ll. Dots represent standard depth sampling levels. Vertical exaggeration 371:1. 57 STATIONS 40 0 DISTANCE (N.M FIGURE 17 58 W. , and is coincident at that point with the 1000-fathom curve. The maximum velocity and transport through the eastern portion of transect B-B', upstream from this locale, and centered at about 24° 20' N., 84° 50' W. (near St. 35), is centrally located between the 1000-fathom curves off the Florida Shelf and Campeche Bank. This suggests that the streamlines of flow in the northeastern part of the Cuban Loop may have been governed at this time by the bathymetry. Transect D-D' encompasses the longitudinal axis of the Cuban Loop, the combined exiting flows of both the Cuban Loop and the Northern Loop circulation present in the Eastern Gulf, and the flow of the eastern semi-circle of the Northern Loop, as well as a large, cold-water tongue extending well off from the Florida Shelf to a location between the Cuban and Northern Loops. Figures 18, 19, and 20 show the vertical sections of temperature, salinity, and sigma-t along this transect. (Figure 24 is also helpful in visually organ- izing the features of this transect.) The center of the Cuban Loop consists entirely of Right-Hand waters; there is almost no motion of these interior waters except for the indication of a slight eastward flow below 400 meters at the very southern end of the transect. The cold, low-salinity tongue of waters extending out from the Florida Shelf, near Sts. 51 and 52, separates the Northern Loop from the Cuban Loop and apparently prevents a direct southeastward flow of the Northern Loop toward the Florida Straits. In this transect, as in the previous ones describing the Cuban Loop flow, the maximum slopes of the isolines are consistently parall- 59 FIGURE 18. Temperature (degrees Celsius) along Transect D-D', 10-12 August 1966, ALAMINOS 66-A-ll. Dots represent standard depth sampling levels. Vertical exaggeration 371:1. 60 < (SU313W) HldBd 61 FIGURE 19. Salinity (parts per mille) along Transect D-D', 10-12 August 1966, AL AMINO IS 66-A-ll. Dots represent standard depth sampling levels. Vertical exaggeration 371:1. 62 o o ro O if) O o CM * 0> z — W UJ ui rr o 2=5 in < o o o If) (SU313W) HldBfJ 63 FIGURE 20. Sigma-t along Transect D-D', 10-12 August 1966, AL AMINOS 66-A-ll. Dots represent standard depth sampling levels. Vertical exaggeration 371:1. 64 (SU313W) Hld3a 65 el down to the bottom of the sections. Of special significance, how- ever, is that the gradients of the Northern Loop flow, in the northern portion of transect D-D', are approximately the same as depicted for all other transects of the Cuban Loop. Figures 21, 22, and 23, depicting the cross-current profiles for transect E-E' , across the western semi-circle of the Northern Loop flow, illustrate the same dynamic features of the preceding sections. The center of the anticyclonic Northern Loop circulation is located at St. 88, near 26° N. , 88° 30' W., as evidenced by the apex of isolines at that station. The slopes of isolines in this transect are not quite as steep as in the previous transect across the Northern Loop flow (D-D'), suggesting that the flow is moderating and spreading westward during its travel around the southeastern quadrant of the Northern Loop. The most significant feature of the vertical sections, taken collectively, is that the presence of the Right-Hand waters is con- sistently demonstrated by the core of warm, high-salinity water be- tween 175-225 meters depth. Further, the waters of the Cuban Loop and the Northern Loop circulation patterns are in motion to at least 1200 meters (and probably deeper) . The maximum velocities of the Eastern Gulf Loop Current, as depicted by the slopes of isolines in the vertical sections, lie not over the core of the Right-Hand waters but rather are found to the left of the core (facing in the direction of flow) over the maximum gradients of the isolines joining the Right- Hand and Left-Hand waters. There is representation of considerable 66 FIGURE 21. Temperature (degrees Celsius) along Transect E-E' , 16-18 August 1966, ALAMINOS 66-A-ll. Dots represent standard depth sampling levels. Vertical exaggeration 371:1. 67 STATIONS 95 0 h- \ r^ V r- 1 00 1 N f O) / N y o a~ '*> co [ oo - \ \ CM CO \ CD ' \ 9 ^ 0> CJ - UJ § I e> — CO o in CO < »- CO o m (W NAQ) QV (IN NAQ) QV 86 FIGURE 30. Profiles of the sea surface from dynamic computations, Stations 83-95, 16-18 August 1966, AL AMINOS 66-A-ll. 87 ro 00 / - * / 00 w 00 I - CO 00 r- 00 1 CO r- < I- q cvi m (W HXQ) 0 7 00 f ^ 00 00 \ 00 \ 100 (N. M.) o 50 DISTANCE CM 0) 1 — o ro 0> in 1 1 1 o in CM o o CM CO z o r- < r- co — w 5 o o t, LU S q: CO e> g 5 U. o m o cvi m (W NAQ) QV 88 Northern Loop and the Cuban Loop. While the contours of the Northern Loop are shown joined in the southwestern quadrant, they may not be truly representative of the flow pattern there. The absence of data in the quadrant permits only the speculative interpretations of Figs. 24 and 25. Configuration of streamlines in the Yucatan Strait (Fig. 24) is also subjectively presented; unfortunately stations across the west- ern portion of the Strait were not deep enough to permit dynamic com- putations to the 1000-db surface. In Fig. 25, however, the stream- lines depicted in this area are based on dynamic computations to the 300-db surface, but must be viewed with caution, as mentioned above. Referring to Fig. 24, around both the Cuban Loop and the North- ern Loop the separation of the flow into an "inside loop" and a single dumb-bell shaped outer envelope may be made by selecting the 1.5 and 1.6 dynamic meter streamlines to represent the boundaries of these sub-system circulation patterns. The "inside loop" circulation within the Northern Loop, bounded by its 1.6 dyn.m. streamline, has a ft o transport (relative to the 1000-db surface) of 29.3 x 10 m /sec. The "inside loop" circulation within the Cuban Loop, bounded by its 6 3 1.6 dyn.m. streamline, also has a transport of 29.3 x 10 m /sec. These figures represent the average of the summations of all the dy- namic computations performed between pairs of stations along the axial legs extending from the centers of these interior gyres out to the 1.6 dyn.m. streamline. The transport within the envelope around the Northern Loop, com- 89 6 3 puted as above, is 13. A x 10 m /sec. The transport within the en- velope of the Cuban Loop, based on dynamic computations in the Florida Straits area only due to insufficient information in the Yucatan Strait area, is 11.9 x 10 m /sec. The latter figure is based on data for just five stations and must be considered as only an estimate of the flow. A summary of these computations is presented in Table V, with the percentage of the several transports to the total transport in- dicated. TABLE V VOLUME TRANSPORTS WITHIN CUBAN LOOP AND NORTHERN LOOP "Inner Loop" % Outer Envelopi 2 % Total % Northern Loop 29.3 68.5 13.4 31.5 42.7 100 Cuban Loop 29.3 71.0 11.9 29.0 41.2 100 (Values are x 10 m /sec) These results are indicative of the state of development of the Eastern Gulf Loop circulation at the time of this cruise; as more of the total transport of the circulation system in the Eastern Gulf of Mexico (taken as a single system) is concentrated within the "inner loops" of both the Northern Loop and the Cuban Loop (and both should be equivalent) , these two features become more independent of each 90 other. At the ultimate state of development, the transport contained in the envelope surrounding the "inner loops" may become insignificant and the Northern Loop may then become separated from the parent Cuban Loop. Without a further source of supply of Right-Hand waters from the inflowing Yucatan Current — even though the Northern Loop is mostly Right-Hand water within its own circulation — it cannot main- tain itself as a separate identity from the resident Gulf of Mexico waters and probably diffuses slowly into them. Further dynamic computations of the transport relative to the 1000-db surface between axial stations and the center of the Northern Loop (at St. 88) support the above discussion of the balance of transport in that system. In tabular form, they are: Station Pairs Transport 88-92 43 x 106 m3/sec 88-62 42 x 106 m3/sec 88-52 45 x 106 m3/sec 88-73 44 x 106 m3/sec These figures are perhaps subject to significant error when consideration is given to the horizontal distances involved between stations (see Fig. 1); nevertheless they illustrate the uniformity of flow around the Northern Loop. VJhen the same axes are used to demonstrate the transport relative to the 300-db surface, the re- sults are similar to those for the 1000-db surface: 91 Station Pairs Transport 88-93 12.2 x 106 m3/sec 88-73 12.8 x 106 m3/sec 88-60 ' 11.8 x 106 m3/sec 88-67 9.6 x 106 m3/sec 88-52 11.6 x 106 m3/sec 88-83 14.3 x 106 m3/sec It is seen that the transport in the upper 300 meters is approx- imately 35% of that of the water column above 1000 m. The flow pattern of the Cuban Loop indicates that some inflowing Yucatan Current waters proceed northward, turn sharply south-south- eastward near St. 48 to return toward the Cuban coast, and then are diverted back into the Caribbean through the Yucatan Strait. Specif- ically, the transport between Sts. 43 and 44 is approximately 7.6 x 10 m /sec, southward, while between Sts. 44 and 45 there is a net ft "\ transport eastward of 8.5 x 10 m /sec. Lack of data for this area in the Yucatan Strait (along the 22° N. latitude parallel) precludes definite description of this area, but the suggestion is strong that there may be a closed loop anticyclonic circulation within the Cuban Loop centered at St. 44. The vertical sections for Transect D-D' (Figs. 18, 19, and 20) give some evidence of a southward flow below 400 meters, as mentioned previously. The net transports relative to the 300-db surface between Sts. 43-44 and 44-45 are 0.75 x 10 m /sec, southward, and 0.9 x 10 m /sec, eastward, respectively, indicating that the deeper flow dominates the water movements in this region. The observed (computed relative to the 1000-db surface) outflow- 92 ing net transport in the Florida Straits (from Sts. 40 to 44) is approximately 45 x 10 m /sec, eastward. Over half, or 30 x 10 3 m /sec, occurs between Sts. 40 and 42, Further, the net transport between Sts. 47 and 52 (from the Cuban Loop northward across the current to the cold tongue of waters extending off the Florida Shelf) f> 3 is 42 x 10 m /sec, eastward. Summarizing the transports of several selected cross-current sections, compare: Station Pairs Transport 88-52 45 x 106 m3/sec 47-52 42 x 106 m3/sec 40-44 45 x 106 m3/sec Table VI lists the relative surface currents and net transports derived following the dynamical computational procedures outlined by McLellan (1965) . Values relative to both the 300-db and the 1000-db reference levels are tabulated for comparison. Direction of flow may be inferred by reference to the figures discussed in the preceeding sections. All computations were performed utilizing the mean lati- tude between the stations considered for determination of the Coriolis parameter . Table VII compares the maximum surface current velocities to the surface current velocities located over the high-salinity core of the Right-Hand waters. It is seen from Table VII that the maximum surface velocities are indicative of the horizontal limit of influence of the Eastern Gulf Loop Current; specifically, the excursion of the left side of the current (facing downstream) is delineated. The maximum 93 TABLE VI RELATIVE SURFACE CURRENT VELOCITIES AND VOLUME TRANSPORTS BETWEEN STATIONS [BASED ON DYNAMIC COMPUTATIONS TO THE INDICATED REFERENCE LEVEL] 28 29 30 31 32 33 34 35 36 37 40 41 Current Velocity Volume Transport sec tcts m /sec(xlO ) lOOOdb 300db lOOOdb 300db lOOOdb 300db Stations / . . 3, , iri-6. cm/sec kts m /sec(xlO ) 139 — 2.7 -- 4.7 82 — 1.6 — 3.9 103 — 2.0 -- 2.6 29 23 0.6 0.5 2.3 1.7 22 18 0.4 0.4 1.0 0.4 87 11 1.7 0.2 6.6 0.4 81 43 1.6 0.8 11.6 3.2 102 77 2.0 1.5 12.7 5.0 44 33 0.9 0.7 4.0 2.3 102 79 2.0 1.5 13.5 6.1 87 43 1.7 0.8 19.0 4.4 94 TABLE VI (continued) RELATIVE SURFACE CURRENT VELOCITIES AND VOLUME TRANSPORTS BETWEEN STATIONS [BASED ON DYNAMIC COMPUTATIONS TO THE INDICATED REFERENCE LEVEL] 42 43 44 45 46 47 48 49 50 51 52 53 Current Velocity Volume Transport sec kts m /sec(x!0 ) lOOOdb 300db lOOOdb 300db lOOOdb 300db Stations , , . 3, , nA-6>. cm/sec kts m /sec(xlO ) 5 1 0.1 0.0 4.2 0.2 44 17 0.9 0.3 7.7 0.8 51 19 1.0 0.4 8.5 0.9 7 11 0.2 0.2 0.1 1.0 1 3 .0.0 0.1 1.4 0.4 11 6 0.2 0.1 1.3 0.8 63 34 1.3 0.7 9.8 2.5 106 68 2.1 1.3 13.4 4.3 68 49 1.3 1.0 10.9 3.6 10 1 0.2 0.0 4.4 0.5 74 53 1.4 1.0 10.8 3.9 101 60 1.9 1.2 13.5 3.4 95 TABLE VI (continued) RELATIVE SURFACE CURRENT VELOCITIES AND VOLUME TRANSPORTS BETWEEN STATIONS [BASED ON DYNAMIC COMPUTATIONS TO THE INDICATED REFERENCE LEVEL] 54 55 56 57 58 59 60 61 62 63 64 65 Current Velocity Volume Transport sec kts m /sec(x!0 ) lOOOdb 300db lOOOdb 300db lOOOdb 300db Stations . , 3, , nr,-6N cm/ sec kts m /sec(xlO ) 31 18 0.7 0.3 6.5 2.3 66 36 1.2 0.7 14.3 4.0 61 1.2 4.2 22 — 0.4 1.5 16 0.3 0.2 7 0.1 0.4 5 0.1 — 0.4 0 0.0 — 0.0 6 8 0.1 0.2 0.9 0.0 35 32 0.7 0.6 2.8 2.2 116 73 2.3 1.4 9.5 2.9 35 19 0.7 0.4 3.3 0.9 96 TABLE VI (continued) RELATIVE SURFACE CURRENT VELOCITIES AND VOLUME TRANSPORTS BETWEEN STATIONS [BASED ON DYNAMIC COMPUTATIONS TO THE INDICATED REFERENCE LEVEL; 66 67 68 69 70 71 72 73 74 75 76 77 Current Velocity Volume Transport cm/ sec kts m /sec(x!0 ) lOOOdb 300db lOOOdb 300db lOOOdb 300db 50 46 1.0 0.9 3.0 2.2 24 23 0.5 0.4 2.6 2.4 51 29 1.0 0.6 13.6 3.7 8 19 0.2 0.0 4.2 0.0 39 19 0.8 0.4 11.2 2.5 80 58 1.6 1.1 13.2 5.1 19 18 0.4 0.3 0.3 1.0 1 — 0.0 0.1 27 0.5 — 0.8 2 1 0.0 0.0 1.0 0.1 13 9 0.2 0.2 2.6 0.9 20 12 0.4 0.2 4.9 1.3 97 TABLE VI (continued) RELATIVE SURFACE CURRENT VELOCITIES AND VOLUME TRANSPORTS BETWEEN STATIONS [BASED ON DYNAMIC COMPUTATIONS TO THE INDICATED REFERENCE LEVEL] Stations 78 79 80 81 82 83 84 85 86 87 88 89 Current Velocity Volume Transport cm/sec 75 40 78 25 32 54 38 19 88 78 87 50 15 kts lOOOdb 300db lOOOdb 300db 1.5 1.1 0.8 0.7 48 21 0.4 1.6 1.5 1.7 1.5 1.0 0.5 0.1 0.6 0.3 0.1 0.1 0.9 0.4 m /sec(xlO ) lOOOdb 300db 10.9 3.6 2.1 2.4 1.8 3.7 3.2 8.0 14.5 4.6 7.2 1.0 5.0 1.0 3.8 0.1 13.6 2.6 70 33 1.4 0.6 15.7 3.5 98 TABLE VI (continued) RELATIVE SURFACE CURRENT VELOCITIES AND VOLUME TRANSPORTS BETWEEN STATIONS [BASED ON DYNAMIC COMPUTATIONS TO THE INDICATED REFERENCE LEVEL] Stations Current Velocity Volume Transport cm/sec kts lOOOdb 300db lOOOdb 300db m /sec(xlO ) lOOOdb 300db 90 91 92 93 94 95 107 20 18 36 20 16 24 12 2.1 0.2 0.4 0.3 0.3 0.0 0.7 0.5 0.4 0.2 11.0 4.5 2.6 0.8 5.8 0.8 5.4 4.2 3.7 1.5 For Station Locations, See Figure 1 99 TABLE VII COMPARISON OF MAXIMUM SURFACE CURRENT VELOCITIES AND SURFACE CURRENT VELOCITIES OVER RIGHT-HAND WATER CORE Area Maximum Velocity cm/ sec (kts) Stations Velocity Over Core cm/sec(kts) Stations Yucatan Strait 102 (2) 35-36 81-87 (1.6-1 .7) 33-35 Florida Strait 102 (2) 40-41 87 (1.7) 41-42 Cuban Loop 106 (2.1) 49 6 (0.2) 45-48 Northern Loop: 101 (1.9) 54 66 (1.2) 55 116 (2.3) 64 35 (0.7) 65 107 (2.1) 90 48 (0.9) 88 (For Locations of Stations, See Figure 1.) 100 velocities observed on this cruise were always to the left of the salinity core of the Right-Hand waters, over the maximum gradients of isolines. Left-Hand waters were found immediately to the left of the maximum velocities. Figure. 26, isobath contours of the 22° C. isotherm, illustrates the general flow patterns of the Northern Loop and the Cuban Loop. The 200-meter isobath gives good agreement with the vertical sections discussed previously in the location of the high-salinity core of the Right-Hand Eastern Gulf Loop waters. 101 CHAPTER IV CONCLUSIONS AND RECOMMENDATIONS A. Conclusions In the late summer of 1966 the intrusion of the Eastern Gulf Loop Current into the Gulf was at its maximum, covering nearly the entire East Gulf basin and dominating the distribution of several distinct water masses contained within the area. The Right-Hand Eastern Gulf Loop waters, with their distinctive high-salinity core at 175-225 meters depth, constituted a large percentage of the waters of the Eastern Gulf Loop. At the boundary between the Eastern Gulf Loop Current circulation and the resident waters of the Gulf of Mex- ico, Left-Hand waters prevailed. These two water masses may mix to form an intermediate water mass having the characteristic T-S rela- tionship of Western Gulf of Mexico waters. The differences in these water masses was especially prevelant in the upper 300 meters, as de- picted in their characteristic T-S relationships, but significant differences were perceptible down to the deepest depths observed (1200 meters) on the cruise. The variations of temperature, salinity, and sigma-t with depth, as presented in several vertical sections across the flow of the Eastern Gulf Loop Current, indicated that while this Loop Current phenomena is most readily recognizable by the prop- erty distributions in the upper 300 meters, its presence is indicated far below this relatively shallow surface layer. The warm, high-salinity core of the Right-Hand waters (salinities 102 greater than 36.6°/oo) exhibited an elliptical- cross-section which varied in thickness and lateral dimensions. The core dimensions observed ranged from 40 meters (in the Yucatan Strait) to 95 meters (in the Northern Loop) for the thickness and 80-104 n.m. (148-193 km) in lateral extent for the same locations. The Cuban Loop was almost exclusively Right-Hand water, with core dimensions of 35 meters (thickness) and 148 n.m. (274 km) (length along a northwest-southeast axis) . This enormous mass of warm, high-salinity waters in the Gulf is associated with steep gradients in the isolines of mass and property distribution and with high-velocity flows to the left of the Right-Hand water salinity core. Stations having T-S relationships representative of the Left-Hand waters were found to the left (facing downstream) of these locations of maximum gradients. The mixed layer depth observed during this cruise was an average of 30 meters, with a maximum depth of 40-50 meters noted at some stations. This mixed layer effectively masked the presence of the Right-Hand and Left-Hand waters beneath. Attempts to correlate observed surface temperature and salinity measurements with the Right-Hand and Left-Hand waters resulted in no definitive relationships. Thus in the presence of the nearly homogeneous late summer mixed layer, surface temperature and salinity values are of no assistance in locating the Eastern Gulf Loop waters. At the time of this cruise, in early August, the Eastern Gulf Loop Current was constituted of two distinct parts. An elongated, anticyclonic loop off the northwest tip of Cuba was overshadowed in 10 3 prominence only by the large, well-developed anticyclonic Northern Loop circulation centered near 26° N., 88° 30' W. Surface current velocities, as computed by dynamic computations, were as high as 116 cm/sec (2.3 kts) in the swiftest protions of the Current, with net volume transports of nearly 45 x 10 m /sec observed in both the Northern Loop and Cuban Loop circulations. Further, the circulation patterns consisted of somewhat isolated closed anticyclonic flows within both the Cuban Loop and the Northern Loop; these interior flows were enclosed by an envelope surrounding the entire Eastern Gulf Loop Current system. Transports confined to the interior circulations ft ^ were equivalent, being about 29 x 10 m /sec, while the transport in the envelope enclosing them was about 13 x 10 m /sec. Nearly 35% of the flow of the water mass movement was contained in the upper 300 meters. Leipper (1967) believes that the growth of the Eastern Gulf Loop circulation in time, space, and intensity may be accomplished by gradual entrapment of waters from the surrounding envelope into the interior circulations. If such is the case, then the relative a- mounts of the transport contained within each of these flows might be indicative of the stage of development of the Eastern Gulf Loop Current. In particular, at the time of this cruise, the Eastern Gulf Loop Current might be considered as having attained over two-thirds of its maximum potential growth. While the observed surface temperature and salinity were of no value at the time of this cruise in determining the presence of the Eastern Gulf Loop Current in the underlying waters, there are several 104 excellent indices which are likely valid during any season. The depth of the 22° C. isotherm falls between 175-225 meters coincident with the presence of the warm, high-salinity core of the Right-Hand waters. (Compare Figs. 24 and 26.) Further, the temperature at 200 meters depth is likewise a reliable index to the salinity core of these waters; a temperature range of 20-23° C. was always associated with the most intense representation of the salinity core. For tem- peratures below about 16.5° C. at 200 meters, the waters were Left- Hand. In the intermediate temperature span (16.5-20° C), the de- lineation between the two water masses is questionable. Measurement of the above parameters is readily accomplished with standard ocean- ographic equipment (bathythermograph) . B. Recommendations Further knowledge of the detailed behavior of the Eastern Gulf Loop Current and the relationships between its water masses and the resident waters of the Gulf of Mexico demands that physical oceano- graphic investigations henceforth be as nearly synoptic as possible. Concentrated analyses of the upper 300 meters must be performed to realize the full significance of the water mass and property distri- butions that are suggested in this important layer. The area in the Yucatan Strait must be surveyed in detail to provide complete coverage of the Eastern Gulf Loop Current at its very introduction into the Gulf. The continuation of Cochrane1 s work in this area (1961, 1962, 1963, 1965, 1966) should prove especially 105 valuable. While the salinity/temperature/depth recorder (STD) is theoretic- ally the ideal instrument for rapid synoptic surveying of the primary oceanographic properties, there are several errors associated with its use which presently limit its effectiveness in accurate water mass analysis (see Appendix A) . The STD should be considered as an auxiliary to the classical Nansen bottle hydrocast and bathythermo- graph techniques of measuring the water structure. The minute detail of the water property distribution as recorded by the STD is not es- sential to the synoptic study of large-scale features. However, the use of the STD for detailed study of the upper 300 meters, in which severe vertical temperature and salinity gradients are significant, does have promising value. For the present, then, its primary use should be in obtaining a rapid analog record of the salinity and tem- perature structures — a "running fix" on the waters traversed, so to speak — until an area requiring absolute and reliable data collection is encountered. Then the standard hydrocast should be implemented. Following this modus operandi, the STD can save valuable cruise time in finding the waters of interest; more time is then available for a thorough investigation by conventional means of the mass and property distributions of the water column. An analysis of comparative representation of the water mass temperature and salinity structure as measured concurrently by the STD and by a standard hydrocast must be made at the earliest oppor- tunity. A large amount of data should be utilized to minimize the 106 influence of some gross STD errors which are likely to appear. The current operational accuracy, reliability, and repeatability of the STD values of temperature and salinity must be established. Further, errors in representative quantitative parameters utilizing these temperatures and salinities in their computation (viz. , specific volume anomaly, sigma-t, geopotential anomaly, volume transport) must be scaled to the variations found between the STD and hydrocast data. Only after these analyses have been performed can the STD data be used without reservation. 107 APPENDIX A STD SYSTEM PERFORMANCE EVALUATION 1. System Description. The salinity/temperature/depth (STD) continuous profile recording system, manufactured by the Hytech Products Division of the Bissett-Berman Corporation, San Diego, Cali- fornia, consists of a compact electronics sensors unit containing transducer assemblies for direct measurement of the in_ situ tempera- ture and salinity (conductivity), supporting shipboard console equip- ment (power supplies, signal converters, amplifiers), and a dual out- put system. Either punched tape (digital) or graph (analog) data presentation is available from the installation arrangement aboard the R/V ALAMINOS. Complete details on the Hytech Model 9006 STD may be found in the manufacturer's brochures or in the literature (Brown, 1963, 1964; Brown and Hamon, 1961; Hamon and Brown, 1958). System specifications are given in Table A-I. Data output format utilized for ALAMINOS 66-A-ll was analog; for each lowering of the sensor package (by its attached electronics cable) a graph of continuous temperature and salinity profiles versus depth was obtained (Fig. 31). Selected data points were then vis- ually read and recorded for subsequent data processing by computer methods. The STD output, in either analog or digital form, requires cor- rection of the in situ salinity values due to the method of measure- ment . Basically, an inductively coupled conductivity sensor (probe) 108 FIGURE 31. Sample Salinity/Temperature/Depth (STD) analog record. Grid resolution of graph paper indicated in upper left corner. Salinity, temperature, and depth scales shown (used throughout ALAMINOS 66-A-ll) may be changed for larger-scale recording of the in situ water structure. This particular analog record was observed at Station 88 (see Figure 1) . Illustration is approximately two- thirds recorded size. 109 TEMPERATURE (°C.) 5 10 15 20 25 300 - -450 LJ UJ UJ o 600 — 750 — 900 — 1050 — 200 - 32 33 34 35 36 SALINITY (%o) FIGURE 31 30 1 I U 1 J 1 GRAPH PAPER ~GRID SPACING — — TEMPERATURE TRACE, — — [ SALINITY TRACE — 1 1 1 1 1 1 37 38 110 measures the sea water conductivity; the output is converted into a proportional salinity signal value via transduction and electronic filtering. As conductivity is a function of temperature and pressure, these properties have significant effect on the recorded STD salinity output. Therefore, the corrections which must be applied involve the temperature gradient field with depth and the nominal pressure effect caused by the falling velocity of the sensor unit through the water. The latter effect is caused by the formation of a turbulent boundary layer around the temperature compensation probe for the conductivity transduction sensor. Following the procedure of Gaul (1967) , as adapted from Brown (1964), the formula for the corrected salinity is S = S*(l ~ \\ g£ (VAx + h)) (1) where S - corrected salinity S* = in_ situ salinity as read by the STD R 8R — 1 ^r = "c (Tc") > tne conductivity ratio coefficient 1 3G K_, = — — , the conductivity coefficient G G oT T = temperature, degrees Centigrade Z = depth below surface of the water V = falling velocity of the sensor unit through the water At = difference in time constants (relative response rates) of the temperature compensation probe and the con- ductivity probe (taken as 0.35 seconds) h = distance of temperature compensation probe above con- ductivity probe (h = 0 for cruise ALAMINOS 66-A-ll) Ill K_, the conductivity ratio coefficient (as a function of salin- ity), is determined from the empirical relationship . . ± BS ± 6S2 _ (2) 3S + 26S where a = 0.038011 B = 0.029435 6 = 0.0000557. K , the conductivity coefficient (as a function of temperature), is a curvilinear function and may be determined directly from a graph (Gaul, 1967) or may be computed for specific values of temperature using a least squares quadratic fit to the graph data. Treatment of data for this cruise utilizes the latter method, with the resulting equation Kg = Al + A2(T) + A3(T2), (3) where Al = 0.029903286 A2 = -0.0005723 A3 = 0.000006648. 8 T The gradient of temperature with depth, -r— , may be computed utilizing either the forward difference or central difference oper- ators of numerical analysis techniques (Froberg, 1965). Data cor- rected herein utilizes the latter criterion: T - T t^L\ = i + 1 1-1 (ii\ ^Z;i 2(AZ) k ; where AZ is the increment between successive depth levels and 112 the i level is the one for which the gradient is desired 2. Factors Affecting Performance. The fall rate, V, of the sensor unit through the water is measured by the STD recorder opera- tor noting the stopwatch time at which a specific depth below the surface is passed during descent of the sensor unit. The descent speed in meters per second is computed from this simple timing pro- cess. From Equation (1) it is evident that as the speed of descent of the sensor unit increases, the higher the corrected salinity will 3T be. Note that — , in most instances, is a negative quantity, since a L temperature is generally monotonically decreasing with increasing depth. IC and K varied only slightly over the temperature and salin- ity ranges encountered during this cruise in the Gulf; therefore the critical portions of the correction formula are the temperature gradient factor and the fall rate of the unit. The latter is the only condition over which the oceanographer has any control. A con- stant speed winch was not available for use with the STD on ALAMINOS 66-A-ll; STD casts were made using the installed oceanographic winch. Resulting fall rates on this cruise were consequently highly variable and were dependent on operator proficiency. For some casts only the time of arrival at the bottom (of the cast) was noted (rather than the complete notation of times of passing various selected depth levels) or timing data was only partially completed. Fall rates, in general, were acceptable (between 1.0-1.5 meters per second), but several casts were made at fall rates of over 3.0 meters per second. 113 Such casts would produce corrected salinities higher than the major- ity observed during the entire cruise. When subsequently plotted on a T-S diagram, several stations exhibited salinity deviations from the normal trend. These stations were suspect and were disregarded due to higher fall rates associated with portions of their descents. 3. Data Reduction. One distinct advantage of the STD system output is its continuous profiles of temperature and salinity versus depth; the fine gradient structure presented allows the oceanographer a wide selection of interesting areas for investigation. Selected values of temperature and salinity may be chosen at standard depth levels or at those depths where significant changes in gradient of either temperature or salinity occur. Inasmuch as the salinity cor- rection formula requires that a temperature gradient be computed for each set of values so selected, depth levels must be chosen such that there are equal intervals between successive points (Equation (4)). Smaller depth intervals (a few meters or less) yield better approxi- mation of the actual temperature structure present in the water; closely spaced sampling points are mandatory for precise interpreta- tion of shallow water (300 meters) analog output, while in deeper waters (where the gradients are small) a wider spacing of points may be justifiably employed. The STD itself records a false output when it senses a large gradient in temperature; the relative response rates of the various sensing probes (Table A-l) are such that the salinity is being elec- tronically corrected and compensated for a large temperature change 114 over a small depth interval, but the temperature compensation appli- cable to the salinity value noted at level Z is being applied to the salinity value noted at level Z + AZ . The resulting analog output shows an abnormally large excursion of the salinity trace in the areas of such temperature gradients. Fortunately, most of these ab- normal salinity errors are recognizable and may be simply corrected right on the analog graph by hand-fairing a smooth curve along the sawtooth salinity trace. No significant errors are introduced by this rather subjective method (Gaul et_. al_. , 1966) . TABLE A-I HYTECH Model 9006 System Specifications PARAMETER ACCURACY RESOLUTION RESPONSE TIME Salinity Temperature Depth + 0.03°/oo on all ranges Infinite + 0.05°C. incl. non-linear- ity and repeatability 0.35 sec, (limited by temp . probe) Infinite 0.35 sec, +0.5% of full scale incl. Infinite non-linearity, repeatabil- ity, and temperature effects 0.2 sec. There are thus three major sources of error in the salinity cor- rection procedure. First, there may be unusually large or abrupt changes in the fall rate. These might cause an unusual scatter in the corrected salinities observed during a cruise. Second, there is 115 the problem of extracting the right data points from the analog graph to insure good representation of the gradients (especially those gradients in the shallow layers below the seasonal thermocline) . Third, there is the chance of introducing errors through incorrect reading of the graphs; caution must be exercised when there are un- usual salinity fluctuations on the graph. The hand fairing technique mentioned above is then especially adaptable but at the same time is a possible source of further error. 4. Data Processing. Considering the objectives of this study, values of temperature and salinity were read from the analog graphs at 15 meter intervals from the surface to 300 meters, and at 75 meter intervals from 300-1200 meters (or to the deepest descent level). This procedure minimized the misrepresentation of sudden changes in the temperature gradient in the shallower layers. Salinity values to two decimal place accuracy were read after hand-fairing the "best fit" curve. A data processing program, written in IBM- IB SYS /FORTRAN IV machine processor language format (see Appendix C), was authored and used not only to compute the corrected salinity but also to com- pute several other parameters of the mass and property distributions for each of the 93 STD stations occupied on this cruise. Data pro- cessing was accomplished at the Data Processing Center, Texas A&M University. 5. STD Error Analysis. Stations having both STD and hydrocast 116 data (Table I) were plotted on the same T-S diagram for comparison. The STD T-S curves were generally parallel to the hydrocast T-S curves over the entire cast depth range, indicating good performance of the STD system in representing the structure of the water column. All STD T-S curves plotted at lower temperature and salinity values than those of the hydrocast curves; mean temperature and sa- linity corrections of + 0.09° C. and + 0.056°/oo were determined necessary to bring the STD curves into agreement with the hydrocast curves. An elementary statistical analysis (Student-t Test) was per- formed to determine the validity of the negative bias in the mean values of temperature and salinity errors (Ostle, 1963). The test showed the error was significant for both temperature and salinity, with the standard deviations of the errors being 0.08 (salinity) and 0.22 (temperature). Another relatively simple error check was performed. Computa- tions of dynamic height anomaly, relative current velocity, and volume transport for the sea surface relative to the 1000-db surface were made for seven sets of stations using both the computer (IBM 7094) output corrected data (STD values) and the same data with the temperature and salinity correction factors (specified above) added. The maximum dynamic height anomaly difference resulting was + 0.0014 dyn.m. , representing a + 0.05% error. These figures are reasonable when the corrections applied are examined in their effect on the shift of the T-S curve. Since both increase, the entire curve is moved a- long nearly parallel to the isopyncnals of sigma-t (density) . The 117 changes in the dynamic computations caused by this T-S curve shift should be small. The magnitude of the changes in this case is in- significant in its effect on dynamic computations. It is not advisable, however, to use STD output uncorrected for deviation from the normal hydrocast data, because the depths at which specific values of temperature and salinity (and hence density) are observed might be subject to significant error and could cause in- valid conclusions in the interpretation of results. All data used in preparing vertical sections, graphs, contours, and other visual aid treatments of the water mass properties observed on this cruise have been corrected to the normal hydrocast data concurrently observ- ed. As the corrections applied are the mean values of all deviations noted, there may be some stations that are not truly representative of the actual water conditions at their location. For purposes of this investigation, however, this method of treatment of the data is not believed to have affected the interpretation of results. 118 APPENDIX B COMMENTS ON STD SALINITY CORRECTION PROGRAM Appendix C contains the IBSYS/FORTRAN IV machine processor language data processing program utilized in this study for correc- tion of STD salinities and computation of the several oceanographic parameters for the determination of mass and property distributions of the Gulf waters. The program is arranged in three sections. The main section determines the corrected salinity for the STD recorded in situ salin- ity using the formulas defined in Appendix A. Data input is arranged so that the program reads temperature, salinity, and fall rate of the STD sensor unit for each depth level selected for each station. The program has the capacity as written to handle a total of 250 selected depths for one or two different constant depth intervals between successive sampling depths. With two constant depth intervals, the program handles two zones separately in computation. Comment cards at the head of the program (see Appendix C.) give detailed instruc- tions for preparing the data for handling. Following computation of a corrected STD salinity, the program computes sigma-t, the thermosteric anomaly and its corrections for temperature-pressure and salinity-pressure effects, the geopotential depth at each level, and the transport potential function for each level. Summations of dynamic depths and transport potential function are made from the surface to the deepest level sampled with inter- 119 mediate level summations shown. This procedure (McLellan, 1965) permits the determination of the dynamic height and transport potent- ial function of the sea surface or any intermediate level relative to any chosen reference level. Using the definitions of Nowlin (un- published memoranda), equations representing the procedure are: 2 6 dp = D z X \ LL X »— » o_ LL i— UJ _l Q >— • UJ CM *— t k- LU k- h- s UJ a: < CJ < CC h- X _J cc Z «. • Q t O- < Q X z Z > < •— i LU 5 z 51 X LU CO X < cc UJ ». z CO »— ^ LU • a Q O > O <: D k- o s: LU h- UJ SI D >- > C s: Cr.' CO LL z Z *—« LU CC e* CC < UJ X) Z CC Cl a: H- a UJ UJ cs: LU cc O < a s: X LL k- LL a: »— c£ o LU LU cO 1— Z i — » •<~ X LU LL LU V— u — 1 ► — i z _l UJ CC t— X LU > < 1 LL < ^ ►—1 Z O LU X l-H a: h- 1" _J < X O a a a. Q X X X < ^. UJ LU o »~t 2S a: k* 1— o z < < co h- >- t— LU Y- k- s: CO cc t — z k- CD •— < ►-H X o h- lO •* < H- Z Q X h- f— CD >• \ K- « LU 2 z a o co > i- UJ z < z a O X X o »— » CO CO > X Z cc ►— « a. a _J > LU < U_^ K- Cl k- CO CO < k- CD k- 1 — t o k- _) t X LU < D- ►—1 X o CC _J — t— *— * ►— « Z LL Z < X a: o (- s: CO h- o I— ^-~ a LU JS. X LU LL 1 CO z »— i LL »* LU CO o LU < o a LU < LU in LL LO a > X UJ 1 — 1 rsj a CO Q >— i X 1— LU LU 2; Q. _l LO LU s0 »■ H~* q_ > — 1 _J » — * _J LU Q a CO z Q£ < LU LU co > cp co \— — X k- co o k- < _J >- < cc < ^ LU CC a: UJ CC X > — i f—t UJ < > h- < ~r~ t— 1 CO i— i 1— ;> >— • cc i— LU CJ a o CJ c CO I— — - z _J _J k- 1 z k- 1 A a; CO o ^» CC LL o >— i »> < ^-4 a _J CO LU Cl LU l-H cd X) o LU LU CO < CD ct: LU H- CC _l z »— LU < g; cr: LU ►— 1 _J z » o \— o LU z CO •> LU X cO o LJ < X 1— CJ LU a cd < >— < — -J z a: t— UJ *— ( LU >- K 1— < LL CC _j a < >— Y~ LU cd CO a • LU M LL X CJ CC CO a h- CO L.i _j cc _J LL LU CJ CD < o£ CL > »— « k- LU LU CO X 1— 1 □ LL o _J LU a »— i 51 < z 1 Q 13 CC ~p < a: X LU _i z ;_•! 1 — i Q LU LU _J _j CL O LL t— > LU O a _J k" LU 0i cc t— CJ CJ >— ( ^ i— X > CJ < Q^ LU + r£ a cr: k- uu u _l Q. CD LU c a z _J LU » CO X LU s z UJ CL O _J _i IX) < a: — 1 < X O _J _J o h- CO o CO LU X cj z u_ O < r>" CO a. CO h- z CJ LL ►—4 Z o i— i k- 1— 1 CO < X LU o X £1 *■ a -^ z a h- HH _J r-t LU >- *— < O X S; CD k- o t— h- h- < < Q ». ~? »—i ►— < LU a UJ X LU Z O oc z z D. h- a: LU 1— o t— CO CO o CO > T" k- co H-* X UJ -— < _J Q o LJ < CD f- 1 * — 1 < CO a Q u LU CJ LU z Z ca c k- < UJ LU O c • a < xC CO z cc CJ s: u CO o CJ X UJ (— LU X * — < X k- k- o z Q£ cc X o LU o Cl K-4 CD X 1—4 \~ O CO CO c£ t— z k- z UJ C_ a UJ -( 3D LU i— > LU X t— t Q _J X id o CO co i_> k- sz LU < t- I— CO ^r. CO LL X < z 2 _J CC ^. H- < □ or CO 0 CO LU z CG a < ►—« >—t r~ £ < CJ LU 2_ CO <— < « cc k- k H CC k- »— 1 LL z r— 51 X •• h- "Si UJ z 1— X k- z UJ cj LU CO CC < o ■ »— < < a: t- •• LU Qi LL X c£ X «— 1 l_) O 51 z o UJ CO LU X — a X o H o LU O □ O CO a I— < O UJ 1— 1 cc or k- CJ ql k- CO z co LU U_ LL ^ z 0. LL o Ql C 1— k- k- < > cc k- LU CL < 4— _J z a X LU CO _l _J > CO < ^-< CO a < < o ll z o k- LU LU < y~ ►—* >— < 1— ry; z LU < CO CO _J X < Cl k- X 2 cj a LU z < D CC CJ < LL Y- < LU < > V- wj < u LU CJ co UJ s < _£ < or X cc L. a: LU z X X X k- 51 5 2 k- X < 2 CO Z a Cl LU LL t— _J LU _J Lj 51 LU k- a c-' CC 51 < < X Ql LU LU z < X d LL 1— a. h-l 21 < oi < > h- X < < CtC CC Ql t— cc jT CD »— < cy: Q. X 2. O o --~ LU > 1— 1 CC D CJ co a. _J CC cd CD k- CO Z) k- Z CD < LU X o UJ z LU CC CO CD CO (— CO X CD o O X Z k- *-H > X CC _l t— r- >- <: CC CJ UJ LU o < — LU z CJ X CC Ql x >— J < X k- CD 2t^ CD CO < s: 1— X Z CO Q Ct^ ^ < ►— i 3L CL Cl c£ CD k- < Cl < ■S- X •* >— i i— CO ►—I LU a. LU co k- c£ i— Cl X X LU X »— 4 CC C _J CJ s: _l z t; CO X _J "T- X k- CC CO CO r\_ k- CL. o Xx X CO — * — i ^1- w— < LU » — 1 CD LU X t— LJ CO 1— 1— 1— < X M ►— i < Cl s: CC C£ LJ *—4 h- < z > _J ►— < CC \- > ►—i O- < Q CL CO X X a: LU LU X LU u X <« > • ►— < LU < LU Cl t— 4 u. LU X LL UJ X Z -J k- k- cd Q k- k- o_ < t~ CO < I 1 — i u. on ^^ z < O LU < 0ft 0 H- y 1— t- z < O LU CtT CO 2 in Z U_ z < < CO < 0 z LU SI CO O X — QC .— ) < 0 LU CC O LU < _J >— ( 0 Z O CO X LU LL t- 0 UJ O SL 0 O _J CtC U.J LU I— ►— < LU K- ( 0 M a 0 X LL •- • • 00 S 0 »— 1 LU t— z ct X — 1 0 J— LU LU z < _J t— Q ^-l Q 0 < t- e) c < > O *-H 71 Z CO X 0 0 ^~* Z »— •" ct: •ft t-H 2 Cl or 1— < 1— O z 1—1 < \~ m t-i LU 1— LU < 1— < • 1— LU > LU X X < »~< X _J co —1 1 1- 1— X ►— i O CO 0 LU < ». O CO X cc co a. (- t- LU S: fO < < O T" O < • I— SI V- 0 _) < co k--* 0 Q LU ^- _J ►— i •> »— i t— f\l 0 < •— 1 CO CC O C u_ < cc CO LU a: •. 0 O — LL ►— t r— 1 t- LU Z LU z O X 0 CO • < -~ LU Cl LU LU LL 3 1 LU h- h- LU t— 0 CO CO \— a X X CO I/O z *-* ft— « X 0 CO z 0 r-l -t LU 1— t 3. a •• z t- 1—1 l-H < »— < c£ » — 1 -~? cC LL LU 2: LU < LU CC z CO < < )- 0 1— K LU » — 1 LU O H- 0 z 0 O X LU Z •—1 SL < ♦■ CO 0 Cl c_ ct: CL LU c£ LU QC X LU LJ t— cc X) O CO h- -~ LU Z) SL < C£ *L- (— 2" u_ X LU M 1— 0 < < ►— H _j >— < a: cO 00 LU LU c^: cL LU UJ 0 LU LU 1— Q X c£ h- < 1— o < ^-> CC X ct: O 1— Z LL 1— CO t in co < Z CL <\l LU CO < 2 < LL «r CD _J 0 ct: *— i •— CO T-* >— < Ci LU 1— ' >z c\j a. LU 0 0 1— QC 0 < 0 LU LL -J z LL *-• LU m • X x 0 2 z a •— > CO > rv: LU > > X 0 O CL 1 X CO U_ CO 0 LL LU l-H _j cO Q LU I— 1— ^~. CO • 1— < CO t— 4 X 0 3: _l z (— O \- J- LL < h- < 2: > CL •^ UJ C: t— < 1— I— H- < u. 0 Z LU X a: LU O LU < IS LU I— r- X LU 0 < < 51 > z 1— • — ■ CC X Q 0 » — ( O cc 3 a: —1 t- < _J > LU > ct: CC O LU CC < 1— 0 (- Z a: LU 1—1 a: Q a: z — h- < O Of )— c UJ c£ Z LU 1— < a. 0 a. < X > LU 2 LU ^ X •— 1 < > _J C!< t— ( < CL LL a i— CO t— l— LU LU h- O cc a: X < 0 _J 0 a CL O > X 5_ r^J z Z CO LL' Q CO CO c£ X O t— X < z LU i£ LJ 1— 1 0 LU CO I— 1 O LU l~ X LU t~ a. X u. 1 0. CO < LU _J Li J >— ■— h- •—1 C O LU or X ». 1— X < z LL t— X _j a LU O Z X LU X CL CO CL h- CO cc O u_ 0 z r-. CO X --^ X X _J c LU < I— CO CO t— t- _J LU CO LU LU < LU _J X CL < 3; f- t~ 0 < LU z Cl .— 1 *~- X < a • LU z CD _i z _l 2: r- h- CL z »-< h- a *• LU H- O > CO _J >— 1 ct: — ' 0 0 <— I « CO Cl LU 0 i-L < CO O _J Q CO c£ c£ LU h- t— < fO —1 a: 0 X 0 ^-• LL 0 z LJ c O LU CC <. LU < CC LU >-i hH l-H X _j < t— O k— * " Q a I— LU a; X _J LL Z X ► — < q£ < rvi 0 LU • i— k 1 cs: X _J Z m LU t— LU ►-. 1_ z o£ Z >— ' y 5; LU ■0 _J * — 1 DT O ijj a *~H SI LU 1— LU (- ► ►— ( k— * >~ LL. *— nj CC < _J_ m LU u_ O f) 1— h- c>_ SI 3T z CO < CO CM Q _J LU CC a a _j_ LL. 1— Q LL ^< UJ Z 1— < LO 1—4 _) . Z < X < < 0 1 X co co a LU CO < cc 1— 1 in 1— LU LU O < CO t~ Q z t— LU 1 LL <—, c< LU CO >■ ►— < LU (S> r- X 0 C£i > Z 0 < t- X LL X 0 rv' h- 1— 0 O ^v Z 0 LL 1— z LU h- 00 1— X O ►— 1 O < O _J >- u_ < z H-< 1— ►— I < O C£ O i— Cl K- -J < LU Cl 1— LJ h- 0 »— ^ X LU Q X LU z LL X K-. Cl — • > CO LU 3 ^ (— CO Z O CO LU ■p^ •—i *-M LU X * — t I— 1 h~ LL CO >— 4 0 h- X X CC C£^ x -v LU LU C\J •-< O O CO < LJ 0 x r— z CO 1— co U_ _J CO Cl y~ LLI LU H- LLI < CC 2 _l • Q£ LU O LU LU t— 0 »— H X < LU Q ► — ( *- < s: l- h- z 2: LU 0 < O < X .■y a. CL »-H O < X 0 LU O Z h— 0 UJ 0 z z 1*1 LL O LU X 0 h- 00 ro O 1— O CO CO LU 1— i- 1— OIL _l O < X ^: _l 0 » — < •— ' 2: >— ' M CC h- m OOOOOOOOOOOOOOOOOOOOOOOOOLJOOOOOOOOO 125 vOrnin^-iryrvjrocsiNtm ro m or < < < < < ►— * < k- i— X o ■4- o m in Cl Z o u_ LL LL LL LL LU LU o Z Q X in X 00 2 a >!" 0. z UJ LU UJ X oo Q 1 O \~ CO Z •« •» • o O X < I- 00 00 O o • • -J oo o X X • 0> 0> o o * z 1— (— CT' o a> en eel X in "* z z O 0> o o H- Y~ r- t- a UJ UJ Z •-' m < * UJ (— 1— X X X X O 3: UJ * t— < < < < CO ► a. * oO 00 O0 Q z z z ^i. » O LU * 3 < < UJ O uj o al * ~3 (~ *- •» ► •> 1— z 1 < 00 UJ OO o 00 UJ OO o < _J < < < _J < CO Z M •s H- UJ UJ UJ UJ > O o z z 51 z < • t- < h- al oo al oo — UJ ^» in uo ►-H (—1 >— 1 »— * al X UJ 3 z X CO o a: CH a: CNJ (NJ UJ o o o CO CO t z CH co UJ •> UJ •> LJ CD UJ UJ UJ UJ LU --» ^-> o < >— c o ►—4 o 00 a OO co co o z z o Q a Q oc 0£ OC LU — o u_ oc UJ UJ UJ < UJ 10 10 LU UJ a. Q — UJ I— UJ t— >- t— z z x X X x CO CO Ql oo < _i 3 _J 3 -^ *=. *c_ 1 — 1 »— t o UJ CO LJ LU UJ uj o t- - H co o z 3 Z ►— * o 1—1 1— X X z z z z h- H- X LL Z 1- < >— < •j- >— 1 X ►— < -^ ►— < »-- 21 < < 10 10 3 X z z \— •— o a «: 3 z 3 51 or o z z a. CL Cl D. K~« »— 1 oo o z CO UJ o UJ o — •— z z a. Q ^ z »— < ►— < U- Z a: > O0 < or Q O UJ h- » (\J * — * ^-~ -~ < z < Z uj UJ Q£ DC < LL < UJ h- 2: 3: X < a — CO m CO m h- a Y- CO Q Q UJ UJ CO t- < >-< h- CO z w-\ UJ o 10 «— •^_ < rvi — 1 v- . 3 X 1 1— l o — - ■w LL K- LL h- t— i t— g: ►— * Cl CO _l o h- 1— l_H 1— CO ►— « a — X O Z O z t— UJ h- uj X LU X UJ X LU o UJ < 1— UJ rvj < 2Z h- .— i Q CD Q 1— cc UJ l-H 1— < Q^ z a: Z t- Z h- Z H- H- -7" O H- 00 > h- UJ < t~ 1 z i >- z < 21 • □ t l0 < CO < O C. O CL O Cl UJ X 3 UJ ^ oo O h- < o < a UJ ►— i o c_ jD 0. 1— isj !- r^.1 UJ rsj uj M UJ z 3 CO X z _i a LL h-H 00 _l -J a y >- h- z z O0 00 a Q Q oO Z lJ t 1 *— ! uj or * t v0 o *g~ CO ro LA CC o >i" Is- o ^4" O in O -\ in r— t •O i—i m t- i~ h- Z a * O ■— < r-l i—i r^ (NJ (\J f0 ro fO <■ 0- m m v0 vO oo < UOOOOOUOOOOOOOOCOOCJOCJOOOCOOOOCOOCOCOCJLJCOLJ 126 00 X X o • o LU (— UJ UJ t- X ^: Q LU z X X LU o X o ►~H o X •> < o < h- « LU _i a. X Q < _j (— < >— 1 3 a: s: UJ UJ < O z < v- t- X I— X < i— Q X • — « s: a: Cl LU < z UJ a > x < < □ • 1- < z 1 H X < • 00 ct: h- K— < OO Pvl CC O 00 3 00 o X rg < a *— < c\i < O0 X LU 1 X < X 1X1 UJ cc •— I a: C • K- s: o CC LU t— Q X X 1- cc > x X i- a Q UJ < CC UJ o z < _J u_ 1— oo ll oo Z LL X LL Z Q X UJ i— i C£ • LL) co < —1 _J i D < k— < < o k- UJ 1 X oi 1— — ~ LL LU UU N LU x X > < • _i UJ X z < oo o CL -J > X cO < z o X t— r-< —1 LU o H- CC o UJ LU z UJ s: ■XI < < or t- < UJ *— * cc LU LU < < VI ^>J < a Qi O a X LU < 2 O Q. h- q: LU < s: oo Di < < o k- h- 3 X LL UJ CD > I X 1— <\J t— UJ a: LJ X Qi Z LU CL l:j O V- 00 O 1- h- t~ X z UJ K- o LU C^ LU 00 00 o rs _J t~4 h- LU < L_J — ' »— i LU LU LU 0_ o I— X *-H LL 00 UJ "V )— o _J 3 < i— LU X z z LU CQ CC z 1— M z LJ 3: oo ci LO oo zz LL < ^J < X t- o 1 — 1 O o X >— < ► ~* LU U- t- X cc —< a CC CtT 1— N -J • > LL M o u_ X •■ 51 X z Y- u_ LU »• LU LU X O < X < UJ o X 3: > < — »— 1 O h- Q OO fyS ■J^ LL _J • > UJ LU 00 H s cC z z 1— _i 00 o _J LU LU O < LJ _J SI CO o X a. LU ft- ( »— 1 00 Cl 2 z UJ D. _l oo •2. 1— z z 3 < a z H cc LU Qi X Z LU H-« X UJ 1— < Q o0 l-H ft X LU LL i— * o < a o o h- t— CC < Q X < in _J Z X X LU Cl X t- * UJ CC h- u. t— z: < Q_ ~— »• oo h- CC t— i CC UJ ►— i —} < (— O X * Z CC < X < ft ► — i LU OO *-* LU X t— 1 •w- a> LU < LU ft z CO # »— ( - UJ U LU _J X LL LL < oi a: CO > < * 21 > _J ►— < UJ O CL a. X _J o i — * M _J \- LU _l X 00 cr: o h- X 3 Cu "N. < 1— z ^ Q .— « < »— * oO LA 1— h- LU _j a UJ ft H- Z UJ 00 i— i 5: □ y- < a. a < Z _J LL 3 Q . — i < x o _j _J (— LU X H- 3 a: LU o t~ H- LU a: ►— i ►— < CC CC o < < X < cr: Cl >— 1 UJ OO Z □ a: LU < X X LU h- • X < >- ^H _J LL □ X X O t— a — u_ 3 u z C5i O o z o z o oo ^-1 X o or: oo _J u CC _J _J CrT Cl CtL ■-o LU < K- < uj s: 2: z < LU UL 1— a z rvj < UJ < < < < o < ». _J O H- csi X oo z < o o ec a: 00 a h—4 o Z H- t_5 1— LU LL 00 < LL X _l LU c o ol o t— 1 LU UJ • CC Z LU o < •> < ^ a: ix. < < Cl a: rS M O 1- CL LL o ►-< c ►— ( Z K- IVI c or ro a o o LL' ►-< 00 s: s: LL d o 00 u S LL t a. z 51 Cj X LU • _J z 'X u LU —-. ft LU LL X cc Z LU LU i — i Q < q: a X > a. LA LL X < LU LU U o rv h- >- o c *— < oi V- o • UJ LL1 a: X t- h- U- a a t— Q < LLJ a —I oo UU < < cr: O X > 1— o o >-< >— 1 00 LL »- Z _l o « _J o LU z UJ LU h- a U- X l~ _i UJ LL X 3: z \— K- 2 > i— i X CL ft > < CrT z X X LU o o < UJ 2 Q o • ►-4 z < □ •k 1— 3 Ul LU \- ► — t < LU X X Z I- a: a: X o o O (V Q 00 _J »— 4 s: t~> ^ h-H cr' l~ LJ z O >— i 1— o o X U) 3 *-H LU LU t— 1— z Z UJ X LU UJ < O or V- 2 Z X LU X <; z —^ cr: X UJ z r- X « t~ X > z < LU LU 00 \~ 1— X oo a. a <. < >— i X LJ oi X >— I UJ < < z X \- UJ O0 h- »—i LU 00 oo X X < CC LL o _l _J LL cC ~. >- CL _J X 1— LJ LU X -J X — 2 < t— CJ LU r-H X j* 1— »— t LU X LT\ 1—1 CQ < 5 h- _J < o < z Pvl — 3 o u 1— < M LU z O rvl z ^-< O0 U- ^1 u_ z _) OO LU o CC X X M < > £< »—i LU _J o CC < o < < —1 UJ < UJ Q a < OO UJ M >- rvl 00 a X >-H O _J z < LU f- 00 O LL X \— CrT «■ err Z s: c< LL c. o/-; t— -J l~ ^ 1— a: *— ( a z CC >- 00 00 I— LU a z <. UJ a UJ < X i— ■ X Q X < LU )—l UJ < >~ U.J LU i— M a LU < z < CC — LU CC UJ X i— o u. LU UJ 00 CC X 00 > X ^ LU c U X r—i Q s: X _J X s: CC c vf X 2~ !— *» LU T^ CC X LU X ~~ LU UJ 1- 00 f- z z t- > — i o LU < h~ X LU >— < 1 i— L_) > LU X < LJ UJ >— 1 1— X p— i _J □ _i LU SI ►-H < 00 ^^_ CQ X < :->t i— r-A < Z ft H- y- 1— Z a X 1 — <; LJ h- z LU z < r< < 1— z < 00 o Di »—i < 2 CC X oO >-H < a ~l cr: > * — i X -- X ►-i LU Cr! H- X a CC 1— a LU LU X -S. 5 •■ LU CL X z nf 2T o o X — I z LU X t~ X \- i— ll O Z a. o c z _j CL < X « CL _J +~-t X a * 1— ft- 1 D X ►— ( CL (— CrT LL O »^-l r: □ t— < X >— s: >~ UJ _J o s a LU _J LJ LJ _j LU * < _J X X -J LU •— i U_ < ft- < Qi a o L:J cc o o UJ UJ X o • UJ z • — i < O LU _j CC * 1— < LJ < < Q 3: x CL a a. CL o CD a. Q. 2 00 I— < ■<— o UJ 1— < LL 00 < 00 < < * * O0 oo 1— LL 00 OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOLJOOOO 127 o S LU I- 2! O LU isj □ NJ 00 LU oo y- LU •— a: Z) < cc —i LU O K a lu _j o LU > < a: LU O I s: _j LU < I- LL LU cC < LO LU LU oo (NJ a X u_ — > K- LU M < •> Q z X ■•"» O > •* o « o *— LO -^ ►. CO (Ni LO --^ r-l -^ f— 1 o »— t- — LO _J o CQ (Nl LU fc— I t- «— O oO U_ t— X — ♦• LU 2 * co « o r-l — i— i o o CL co »— LO •. •■ f~\ o (NJ *-* — — X «— LO o s: K _J t—t LO cc — . < — * (NJ LU CO OO < — ^r- 1— 1 a ~ 1— Q P w- - v0 LL O X M r— . _ LU CC •» CC O f- o D- r— < lo t— o •» co co (NJ •• •> — > r-l <~N wr ^~. ■~ O »-• X _J vO LO LO (— r- _l r-l (NJ o ^~ < 00 — ' — > — 1 CO LL. Q LO _J LO r-l •■ •■ co LU X — r~. ,-, < O *. M o lo t~ CD ^~ r-~ 2T LO ~ •> > o CO >- (NJ O ^-~ < LO r-l C — (NJ LT\ ♦• (NJ ~^ X O — r-l — •-» o *• 00 LU -— O M LO — ~ •. o f- LO O X CO *-^ *> CO (NJ CC •> r-l O -- < •— - < r-^ — LO <0 1— o_ CD CO r- LU (NJ (NJ *- oo r~\ 1— < 2f 21 — _ «--« _) r. — •—i r— < — ■ o o LU ~^ 1— o_ (— 00 ^ lo Q o X"C X ». »• t — ( (NJ •- LO •* •■ **f — < — — « f\J — — < o - O- LO •«— CO co LU in — h- r-l o r-l r— 1 >- CNJ o _J >-- •* ^- ~- •■ — in LU CQ «— M *r^ >- (— (NJ Q LO o X o CC >— t «. r— 1 a ■— 1—1 X O a: oo — oo o _l 00 f* i^ UJ 2 O 2: »- LU 2 ^~- o LU LO LU -— O LU 00 _l LU S (NJ 2 LO •v s: r-l < LU 1— a s: Q »-- O Q _l c£ *—< i—t r~< (NJ r-l 00 -J LU > LU a. LU D c CC < a 00 2: c < LU C£ CO (NJ M --- >'. O •—■ t —■ O LO L!_ (Nl ro o D 2: < -• UJ 0 oi LL lO f\l O- 2: < cj: cc c < LU a: + r— * r-l 1 1 *: *— 0 0 z < -0 r— 1 <-- (NJ < (NJ »• II II OO r— . ~— II M r-l M ^i »-^ •-.- w l.; O O r^ LJ O U <-) U> 128 SL •— t m o r-l a X « X v. y-* 1— < oo »* r-l X >s 1- »— «*• *h X _) X •i 1—1 X "v P« in or X o < CO h- »■ CO •• CC r— 4 <: .—1 *■ 00 *• X - < •t UJ •• X X > X 1- UJ •J" > (NJ vj" 0 l—l a O r~> O >- ►— 1 •> <— I in z i» 0 0 ► z •a •k X •■ •K t—l 0. > V X X —-» t~ X \ X 00 < 0 U- t- •— 1 z iH •» r- _J X m Z • o »o 00 *> UJ r~ X + X o in s *>■ al X c> •>- r- 0 r- s: U_ < \ UJ r-» X X » 1—1 ^ < — •- •k \— V* in --I X X X *. (NJ > in UJ _J »v r- •—I l—l > •» < < s: < X •» x •> < r-l c. •. 00 r-l ^ CC D * •• m X •* »— 1 9* *■ o (NJ < h- cC CL SL 0 X M (Nl u_ o •« •> CC »— < 0 r-l Q O ~ 2 X >t O _i Z V, - * z r— 1 o (NJ r— f O UJ > 0 uo o • _J - » X 0 O + _) X >t cr. x - r-l u_ — o m Q- 0- l—l >c ». «. X X — . — o i— < m -z. < UJ h- « ■ — 1 X X in — i r-l (M z ♦. >— i o »■ O X> fX »• r-i 1— 1 •» r. f— I •— i o i _J X O SI >: ■» r- X »■ * _J O (NJ — i * r- 1 (NJ ^^ u> 5: X >- UJ UJ + a. ►» r- (NJ (NJ * H-' *- X r- < un X 0 0 O UJ -~ r-~ h- M (NJ < v0 r-l z •>* in X r-l Q r— 1 >— 1 < < c — _l < r-l t-H X »• O in X — -— r- _J »- «* < r< »■ SI 1—1 X > *• X co CO < < r-i m »> X X •h ^T < X m x ^ —~ oo h- o •» M < m ♦. x - r-l .— 1 tu 1JJ C3 r-l - <\J H Z *» . . UL 0. 1 «> 00 r-i X *. ». o o z h- CM >-< < o ^^ \ UJ < X CC ►> r-l l—l f— 1 O o r- < < h- - _J *rW ♦■ »» K- c s l—l UJ un •■ II II f •• > _J cc in < 1— t— OO < w r* h- + 1- r- 1 r- 4 r-~ u_ < < < •» < 2: s: 2; X r— 1 UJ 0 z •* •* r— 1 1— < >— 1 r. y~ - 1— 0 a c^: 0 00 _J X r-l 1—. .— , — — 1— oo m 3 00 x X 0 •> X UJ X X ►— 1 r-« < < z o ► < r-l X m i— u_ X r- 0 0 X 00 ^- «-- 00 h- UJ » — i f H •» 1— r- n < in •* »- on 00 CO I— IX U- o v- 1— in c < •v. UJ CO CD . — UJ UJ ~-~ I— 1 < ZC < o V- X > — < z v. 1—1 > in X c£ < < i—i CD o co i- < ^ o O0 r^ vO •- x »— « \ ►• < •» (Nl 0_ K- l~ t o o • Z 00 l— m o — t— in X CO 0 ^^ \ _j X \ r-l X w- — in — -— o o r— 00 < r-l r- > < - (NJ •» < (NJ •• < CO •>» - O .-~ r-^ U_ — — CM r~« o r * + o u. r-A O l!~\ UJ 0 O 00 r* 00 •• O O (Nl r— 1 I— 1 UJ h- o (Nj vO UJ ro t—i X •> t~< X ro X X z X ro ro —I m m f r-l ^^. »■ •> 1—1 u_ r-l < O r-l •* •. _ «• ►. ^ r~ *> 2 — »~-4 o H- ~.r •> CrT 0 »— Li_ •» CC O - in in 1— m m I— OO in - \- 1— ^^ O V- f\J O < — H K H \~ *N _ ^- < ^_- •~* < w r-A r-l CM h" r< U- O m X r-l UJ co CO —I vj- in o o o o o o 00000 129 \ oo o LU O >- < ac <. O C£ UJ M O m CM O vO f* •» ■ » t— i r-l O 1—1 ii II II II 0 0 £V O *— oc c t s: 21 al LU 51 0 0 LU S. z> II II D c—l r-^ r» 2: t— 1 '— *~. 2 o O 0 >— < O CC cc »— 1 ^ •J- **_ K- r- ^_ ?_ V- — ' 2Z — w 2 o □ LU 0 0 I/O 1— 0 D Q a 0 .-1 0 0 0 y~ O »— < •— ! O O 1 O 1 1 LU LU LU a^ O h- r- >t CN 0^ c> O 0 0 LA 0 f— I f^l 0 0 «*• LT> CO O LT\ in ro r\j • 0"^ • • O « O O 1 0 11 Ii II < II <. D 1 : C O ^ O 2 O O LO 2: s: a a s^ »-H *— ( o u o o o o 0 130 o — • "» UJ ►-H 00 0 — f— < o lO «_- 0 0 w- 3 %-* + • 1 * 1- * < ^^ 0 UJ • ^_^ o SI s0 ~-~ r-l — » z 5: r\j )— H — f— 1 < < ^- 0 0 • h- * 0 0 UJ * z 0 •O * > — 1 • z • UJ • + — . ~— 0 o C\J + 0 0 1 1 — 1 0 * * to «~ »— » U- ~- CO *-. ►— 1 UJ 1 — i UL CC >- r- O — z «— U. 0 »-^ • m h- o 1— 1 IU _J * «t 0 0 M 00 * O O 0 * O + • 00 :£ < — . m *~\ t— ( + O 1— > CO • — + • LL Ul en 1— 0 CO 0 t— ,_, f— 1 UJ «— > >t IT, — . •— •n. 1— "v. ►— * • — in 1— --^ < — 1 1— f~i \ Ow' * w— < a: • O + Li- O r~ i CO >*• 0 0 _j CNJ a ar • 0 0 • _) * z --• 0 m 0 ^h 0 < * 0 — . _j CO t CO * u. »— 1 0 2 5 0 CM + 0 1 1 0 ) , o «— a: O »— »-« ^~ 1 •^ z •— < 0 * — 1 —~ y- < ^^ 00 u. Q 1 UJ (— 1— *^ 0 » — 1 »» M # s; h- r- «— # y- 00 UJ *~* O < < D O in * m * — CC 51 * s: a: * in • — . >t r- — Z) r- »• t s: 0 O O T—t r\i CO 0 1 t- s: »-~ ^ CM < 0 x: CO 1 * 0 ~- 0 C£ # 4 u. ~ t— 1 t-t m or *? r •— < rsj V. M + c a: r-l a: — 0 0 >i" U) n S£ •* O ^- O . — CD ^ v> O cc 0 • 0 n ►— < II «-• v. — ■ V. >— 1 ID ~- — > ^~. _j 0 • 0 CNJ 2 i •— t i — i »-~ •— I ^ ^ 00 1 H-4 O 0 ■ 0 >-~ r*~ UJ — r. ^-» »-» »— . — , 1 . — , ►--H • — ra * m »— «— 0 h- »— < —n CM _J en in 0"1 l-H r-i r— 1 ^~. 00 Z 1— 1 KH O ^ I — — • ■— 1— 1 • _J « LO in «-« — ~ 1 ►— i <: O — - 00 • in --- ■ — # 0 •» l-H — in < m a e» )— | — 1 — t w < ►-^ * 1 0 l 1— < 1 ^-> 1 > 00 t- ta- U- U. l_ (M 1 1 ^~- _j h- h- -— — 1 Ul -^ f <- • K -— — - in »-- IT\ 5. o in — »->. h- _j UJ O — -— ►-< -— CO i- ^H CM 1— < M ► — i -— r-5. •-j «— —1 y- cj^ •* rA c— 1 1 < cc z 1— 1 >~^ ~— »— * c> ■— — ' rr -^ Q Z .-H i—4 »• fNJ »• - •~. m + + ,-, u. + ID •. ■~^ u >— » *— * r-l — + ►— < o o X O X Z s: o ►~i l-H l-H * < U. 1— ►— ^ c^; O m 1 —• • 11 o_ --- _) UJ l—l ■— < >j" r- 1 vf- II « m --- ^ —■ LU 3 X •— 00 II 00 •-^ 11 — V— * CJ ^. K 1— \~ D < a. — z > — ^^ ~- —* ^n CNJ 1 »— t UJ ~— 00 2" Ln LO H- m I— UJ t— i — — 1 m □ — 0 rM t— i — » »-• < v_- -' < 0 O 0 0 O0 UJ — l-H UJ UJ o UJ UJ o UJ O O U_ u_ H- o i □ I— o o a: * UJ -J or UJ Q CC o LJJ > 3 O LU 00 z o 00 LU t— 1 1- 1— < t- z Z o < ►— 1 3 o t- O a- <_> (\J o o o> .— . LU O vO o o o 1—1 rv" o o in LU h- *-» -~. «—• of 1— h- C\J O K- 3 •— < 1—1 s o o o s: t- O O Osl — »— CC o o CM o •— < o UJ — i — ( »— _J LU »-» 1 *—^ ». o _J ro *■ O --^ — > < X »-> ro r\j .— i >— < «■"* LU « i— 4 i— i t— i 1— « O0 1- a. t c • .—1 OO i— l— l —~ O0 ^- «— _- Q II » h- z i— i i- n LU • LU _i (\l II » — t II 1— 1 O 1—1 II -— LLI LLI O0 _j + i LU _j Z> LU z> LU « Cl l— i w ^ w 00 00 — . ■^ 3 ID ^>- * r-| iH 3 • >—i Z _l 2 o f\J (Nl z rvl ^ (~ II II i^ ■— z z r\i a. r- O- X C *c 0s -^ (— ~-» ^ ^ .J a: + (— h- t— Z II a II h- 1—4 vO z « Z or ■w Z II II m O i^ w •— < LU *: z z _j •~- <\J h- CM Z — ■ o u. o C£ LL II r— 1 fM CD w t— < •~- o 1— H CO I ii o a LU u. 51 a ;/ o U_ O O •"-< o < » — i ii fc—4 k_' a fvi O0 H- 00 00 O 1— ^ o o Q ►—4 i — i (j » — » u •-< a o t—i o a> (M r- 1— 1 o (> o O o o o o o o o o o o o 132 to CO < LO < o to I to CO < cm m sO to vO vO a: ro CM m c vO o a CM CM o t— o 1— o fft a CM O c a o c 1 (M \~ CM t- t- o h- o 1—4 □ o o a o -— CD ~ to ^ i— ! I— o t- C5 i— 1 o -~ CD «-» oc o i-4 CM O '-^ O -- vO »-• i—i --- 1—4 o k— 1 <\l a O ^ CD — O »-. + — » + cj> t— o \— ^~. ^-4 ^- »-4 1— -? -j "> ~> i—4 CM — ' o C V- Q «-» + — + o — »— ^- •— < < -^ LU (X1 o ^5 —> ~J —} "5 o to to to to \ ^v »-- or □ o — •^ --^ «_- ^- ^~ & CO f*;"*, CO »-~ «-~ 1 C£ h- rvj — ■ o V- \- (_ |_ o c < < < < -— — - 1—4 CM 1—1 O 3 «i_ 1—1 c • rC; uO co co 1—1 • i~ h- h- 1— 1—1 •—I co a to o CD 1— 4 1—4 • o < < < < •» o + 1 l a: o ^~ ^ •■ o r^. 1- t— i— y- r- 1 • o h- O 1— O 1— _J ~i -J —> -"} *~* '"■* 3 CJ • o O- 1~< « i—l r-4 • h- « 1— • • « 1— H- II UJ • t • • < < CD co — ■— II II ♦. h- II II LU O _J O O -J t •— «-» — « — to to to to NJ rvl »— LU «-» UJ LU I— _J « « • « t • "5 ^~ I— 1 • — < ►— i *— « LL U- LL LL '— » w i — i 3 >—* Z> 3 > — 4 1 — 1 -) — - »-. •— . -— --~ ^-. ►— H — ' >— sf- • — ~— >d- LU UJ LU LU II II «— LO 2 LO — z 2 <\J »— 1 1—4 ►— « >— ' «* *— i ► — * vO — o o o u O o 3 a a o .— 4 CM C_ O i—i vO c >— 1 ►— • < y LO rM --^ ■w — - — CVJ ^^ ^« o M to to 10 to to O O o o o to to LO o 1— o to h- h- h- ► — i (\J r\j 1^,' t— h- 1— a t— h- •>— »— >— I— — ~— h- II ii II II CiT CC _l 1— ^ 1— _l 2? Z _J ^-- »— fc^l >-• • — h- »-- — ^ o ll U- LL Q LL LL o i—i f\i r— 1 CM o o LU — o a o UJ o □ UJ LL o a LL LL LL LL a LL. LL O ►— < H- 4 •"-' o •— < >— 4 o < < CO CO O o 1—1 o o CD a o u> Q ► — i C ) o 1-1 i — t »- ■-* i — i LD »— i ►— i ro vf o r-l LPl o ro sO >o nO vO o o CM o o u 133 + -i CO < CO < h- l CO < CM C- a: o o I LU Q + 00 X o o h rsj — < < ~ \ \ — •-> w-t CM I— i r-< co co i— + i -J — « I cc- < < co t~ I— h~ LL U_ LL >t LU LU LU MODO o o cj o I- II II II O •— ' C\! i— i O < < CO CM — ' o — II CO — - I— M U- — LU II O -i Ol-HI- II CH c£ _l CM O O LU II — CM Q_ LT\ (XI o LU 3 LU LU in — 2 M0.H o I" l~ i— z i- _j z z O O O LU o o coooo-- cjooooo a. LU Q O »— I < z > o o Cl o o LU Q + CM — O LU I \— LU II 3 _l z LU O O O O II • • — o o CM II II *-t CM CM — • 21 'Z. o c t- o o z > a: -i in h- O o m in m I C\J Ox Z + r-i rn a. s: Z <-■ — Z II II r-t -~ ro lt\ — a. s: 2: o « o ii a o c? •-<•-■ «~< CM CM HU>0 CM CM CM vO a. r- z o II I- m o s: o ~« in CM I CL Z II in LU z >-. CM z a a o a r- U> 134 --H (XI Q • — • ^» CC «-» a. CO (M < r-H h- u_ t C Q Q > t-H _J •>■ co z Z 3 Z < i—t LU X LL < < li < 21 ON O w-< *> Z t- 1- •» +~ X o 00 •■ oo _l • _ ►— < CM • ►—1 1— UJ on LU co r— X LU > 3 Z — " — r- CNJ < X h- G LU lOLL • V- I— LU _J h- r-H _1 t— d: *• »• r- — i r-H <- 00 X 3 LU ;r G 21 h- »-- •• X r—» 00 _J a; Ql G z LU •- M m 1—1 * * * X 1 — i UJ 3 LU r-H LU I— — > D • »- # >!< * I- _J cc L. 1— a: 21 CC < r— € a: CO L^ * ft ft a. u LU < LU 1— — - < u_ • * * ft z 21 O0 CC LU X Z U_ G r~ CO •» ON * * ft •— < a _l LU ct: y~ > LU o a X LL * ft G LU Q a: G CC G I— • •■ f-l •• * ft c G > c< G •*■ Z — » to ■*- r< X * LU ft LU < LU O G oO 1— CO r— 1 — •i »-< ro i— i * z ft a _J CC < a Hi ►— < — — ■ • ■ * ►-H ft 3 LU z Q LU X 3 •»- >— I M h- LO * h- ft _J C3 < t— 1 _l r~ h- o G t- <-^ Z U- • * 3 ft G h- •^ LU G o -J »— . Z _J >- •. ON # O ft Z Z < r-H 21 CC o 3 in 1 > — i a. < 00 o X r-4 LL * * CC ft ft ►— t G z 3 o UJ Q >- O LU Q i-H G LU — Q »-» r> X * z ft X 3 < 3 o ryr LU 1 o * •- ►—1 CO i—l # 3 ft 1— Z a 22 21 H c 3 X ^ • — ■ .— •— ♦ •« * K- 4 ft 0- a LU h- — 1 h- G r-H o ►~i 3 CC CNJ * \~ ft LU >— i OO 00 < z G w • «— O U- • * < ft O f— < K r-H _J z ^H a X * <\i HH a: »■ CO * _J ft < cz 00 3 < h- G o ^^ \ 00 a. X LL # o ft a j < z 21 X oO O • —•- -^ •■ ►- •—I «> * a. ft cc o a LU 3 Qi 1— 0£ G 1 CNJ *— 4 — -— ^» «• X * dL ft < a. LU _J h-H 3 UJ > V •— ~3 ►— « ►-h (N •—I * LU ft a CC z H- U- D£ 1— » — i h- — . V- — • — •w t »» * i— ft z LU » — 1 I— < LU G 1— 2 --~ Z M g _l LH (NJ * z ft < 1— >z < t— z 1— 21 < G "3 ►— < .— . z oo LU LL t * ►—I ft i— z CC 3 3 < _J 21 •— D- v-H >- ♦* Q •• CC * ft 00 *— 4 UJ UJ D_ r-H UJ O G G _J ■~- «-' a *-* O X LL * X ft h- CO 2: 1- c^: O or t- LU # o + * — i > 7-4 »» # h- ft 2. X LU 3 < G o < Q ^~ o .— * r-^ — < r. X * Q. ft 3 G o (— G _J r-H G 1— + — • a: r-H >-H h- •- i— 1 1—1 * UJ ft 51 ►— 1 00 3 OO < oO — • ^-» > — i Cl — -^ •« ~-. • •> * Q ft i—i X 00 3 < Q. 1— 2 > — i *-H h— 1 w. + M l-J, .—. r— 4 s0 CN.I * ft X 1< r-H 51 a: 00 3 t— LU «-- «— G --~ 2! a c\i ►— « «— u. t ^ * O ft < IT LL! < _J z LU G M LU r-H >- a: 21 — _l •• LO \ * CC ft 21 CC •« LU G r— LJ G LU 00 LU 1 O «— Q < K-* ISl LU X LL \ * < ft o c-- a: •— t z CC 1— — D r— . o M ^- CC «- ^ C! Z •~- Q f— 1 co •- •> X r— 1 *• * Z ft Z X 3 3 00 Q. a II <— < >- II + o «— r— ( f— 1 c * < ft «— < 1— r» t— z u_ _) UJ *-^ N — o — -— II ro ►—4 I »• i— 1 x * 1— ft X 00 X CC < LU h- K >— < II II li ►-H i— < LU ». «-• •— i (XI LU *» r-H * LO ft O0 <^ UJ — 3 r-^ —- > C-l 3 3 1 — « v0 a. w 0 3 >o »— * ft t—4 G a r-H LL G CNJ LU 3 Cl -J ►— < m —> r-j G Z •— LO 1— L^ 2 «-- H * ft _J z — Z •~~ _J o_ y r-H UJ w- w *~* a II »— i o UJ _J < LL ►— * LU < * * ft CQ a » — < X l~ < II II > *--< a: >- cc »— ■ O o cc *> □ .— 1 a CC O # * ft oo v. _1_ LU < < :-■ UJ ON -5 < Cl Cl Q a G u CM o 3: i— 1 u. o F— 1 o o li LL i—l i— < * * ft LU O0 1— D G c h- Q : S^ G GGGGGGGGGGGGGGGGG 135 1— 1 rn o o CM CM rr> a O O K- I— CM o o O o o h- '^ — O »-« ■ — o ii ^ CX LU o o a: < a CM m M N i£ CO X X — 1— 1 • « M - I— o X — ' CD LiJ • • • Q) II — >— LU t-H ■— 1 ♦ -< 1 1 ^-~ *: <\j CM CM LU LU 51 s: s: I—I vf vj" rj Z> t— 1 ►-! ►—4 i — i 1 O O 2 Z o ~ — — 1— 1 CM #— t CM M t— < CM M fS! M i a> I— O >— h- _J O a O o CJ O < t- »- o h- CD CD in 1 o a ^~ o -^ — ■ .— i Q CD CD »-- CD •~~ ~— c^ LU — «-~. r-H — ^ r-H r-4 o O m --* «— + .-^ + + h- K- ^: 21 X X x x X it: X X X x X X a CD O 2 * — — — ■ — • •— — - - — r— 1 •— ( >>l • • • • fvl • M t • h- II 11 o LU CD I— O o LJ D. LU _l • t • t t « • a ^^ •-• »— •-• ^~> — x X —■ --» ^- ^. «-n ^-» ^^ ^H r—t CM r-H r 1 oj x _J _J J _J _J _J r— 1 i^ 1 ^~- »— + + 1 ^-» + + *H X X x vt" X id X sl- 1 UJ ^ yi ..j yH ^ y; ^: ^: ^: 1— I i— < »— — w r-l ^ *— »-» 1—4 ^ > ^ ^ i^ k ^! ^ ^ ^ ^ «— « r- < SJ ^J NJ o rvj M M Q\ ^ Ci a- o- X X X o X X X o •w- LU M N>> M M M h- H h- I'- «— w >- h- «_- >M> _ 1— — ot 1! II X II II II II ii ll o o LL LL LL o li- LL u_ CJ LL CO f— I CM II en ■4 i—l r\j ro — 00 ~ ^ • — h- •-» m • — ■ r~* tmf --» rn »-- ro XJ + — NJ ro M + M 1 . — ^ 1 XJ 1 1 ixl ^» 1 IXl IXJ •J- NJ — «* «— # ixl XJ + •—• * rxl * (X 1 1 i^ * CX 1 «-• co ro *- ^ »— «-» h- ro •— < —* XJ r-t "^ t- r-l «— xj ixl 4- — + XJ z M + — 1 — ■ * 5^ ^ ►—« 1 «— . * rxi «— > -^ X. N o N — — 0^1 ex ^, ^. 1 * CXI rsj CM M rvj X.' 1 rxi 1 XJ ^ w» r-l >f CM 1 1 i/) ro ro X 1 ~-* r- ro xj ro xj + rxi XJ >- + •— »-- — * *-- ■— I ^« r- »-» * —~ -— -— X 1 XJ <— < »— "— « \ ro — < — _J X z m i— i •— XJ rxi '— ^ 1 *— -4 XJ NJ —- 1 1 —^ ^- _J 1 1 «t i— < ro XJ h- XJ _J < r-l ro Xj XJ rxi 1 r- 1 X ^ CO M xj 1 — — XJ z 1 — — — ' XJ * •-- •— in h— < ^- XJ D * «-^ — ' LO X * • _J _J X z -~ \ * • CN ^-» — o < ^ — < (M -~ — 1 o xj — . (X * CO — # NJ ~— CM * 1 t\l XJ r-. XJ -- CL 1 CX 1X1 — . r— 1 XJ 1 --. o X — S i—i IX! 1 *—. XJ 1 .XJ — > 2 — . ' r-t UJ M 1 1X1 .— . -— XJ »— ro < * + H- — NJ «— ro — »— * XJ — i^ v- — ' * IXJ x. * ro 1 CL. — ^ LL N # ro 1 — •~~ CO si- 1^. r-t -~- o ~- -^ t— 3- CX >— * XJ XJ 1 ^ < -— * IXl ixl * ro. 1 1 2 •^ w _J * ro 1 1 '-^ CO (X ^i- o ^: o a — ^ h- ex vt- (X — XJ XJ r—t i^ CO a. CXI w- xj XJ xj + — ^-- 1— — — csr IS] + — — • 1 ^-» ■1* *" < y~ — UJ 1 _J — 1 \- NJ , — — \ ~-- ro ro *-* 3 .~- ^ z — ro ro <— * XJ XJ — CL 1 ^ 1 — 1 $ rsl XJ r— f— i 1 1 ro Di ^- *: r-~ r-» — .—1 1 1 ro CO CNJ (X XJ U_l >i — t— < r— 1 CX 2! h- CX C\l IXl w XJ XJ 1 H ^ u 1 *~. + + < ^ rxl xj 1 — *-r >-- XJ Z — CO *: .< v: ii r- 1 ^ •— ■ — xj II if. -— — — t h- II i£ ^ ^ ^ / r» II * >— **• — . — x^ f -o II — — • w w — z — - «-i S * _J i— l -~- -— r-t OC — _J o u o l_) < _J r-l — ^ ^» ^ xj *-• (X & < _J yi (SI CO CO to cr: ^ XJ — (XI •w 1 — < 1- CO CO CO CO CO _J X IX! 1 rxi X --- XJ — O _j X X r-t (NJ ro i-l OJ ro (X — . 0 ^» • r- • «-~ h- O co r-l sO cc r~t O + r- + O — • — » • _J — < Q < U- LO " r-t CO > cC • in CC X O 0 ro cc • + z >- _J 0 r-t O • < V- 0 LO CO 1 r-t >—i * «— 0 . — «— - z — \ 0 -J X, >- >~, CO — » vr _J _J 0 O 0 -^ r-t < < r- • 1 h O s; (vo vf ro —* X O o • co _J * • 2! C r-t ex b^ r- O < z: + + «— vO * < U- *-» r- vO '— o cC _J X r-l _J ►— * 0_ 0 ^ * O i^ a: s: _J «— ro • ^- UJ UJ 0 I- si- O 1— t~ r- * X co — O CO »-^ — ' 0 «— ►~i O I rO i= r-t —- CO >L r- 1 — » O * X CC D- 0 UJ 0\J O — UJ LU in r- * • •sf ■—* X O 0 LTv * O (X 1 1- CO • — - ro r— o • r-t cc •-* r^ ro •• CC r-t 1 CP «-~ 4 ^J" r- < X. U. • 1 O vO 1 O — ci ro. • 1 00 < z 0 0 1 ■— t O — r- 2: < ro _l -— . ^" O ^-» O 0 H- O 0 _J ■V 1— 1 *^ « <-< CO • * ^. *— co 0 O CO O ^-« -~~ O o t> o o u 000 i_) U LJ U 137 + CO CO < 00 CO < X OO 1 OO X -~ X h- -> K- 0. •~- C UJ oO LU O I— 1 r-i CO < Q o o o K O r-< r-* on 1— 1 m r~l o ■— CC O o < o v0 o n0 * < H ro f— i CNJ Q n o o o *— o Cj CNJ o CNJ 2 •o t— o h- CNI 2 m O CNJ o < o o o o OO < t—4 CN k- CNJ I— h- i— t H o 1— o ct: h- r-l o a a O o 00 1 o <— 1 o O o r-l + a r-l + o i r-l 00 1 o CNJ a r-l CNJ a t— i~ o r-< a o CJ3 p— i LU r- ""3 -3 -3 "3 1— 1 00 00 LU r- o ^~ + »-» + z: o ~— -^ —' — • < < ct ■z. a o -3 -3 "3 "3 ¥—* o 00 00 00 O0 V. *»N □ 1 — 1 o r-. •w — — •w- I— — . CO CO ~*> co — ^» o y- . — o 1— r- 1— h- Z> o o < < < < r-l CNI — D r— ( o • re C0 co CO o c 1 * r-- 1— 1— h- CO CC — a — 1 • c < < < < Qi •• o i • • • .-. r-» 1 1 — C£ ** o 0"', l- r- r- h- 1— 1 • 1— y- h- I— t— 1 r- 1 • — ^-~ 1 r-l • • • • • t «-~ G _J O O _i «— + ~- + _l _J .— < »^ G 1— t- h- r- r— 0- II UJ t t • t -> ~3 —> -3 ^ i/ O0 c II LU o _j CD O _J •> t — - • — • . — •~- «— »-» ■ — «-. — ct: o •• • t • * • • O0 —) »-. -J _j _J _j < < CO CO NJ rvl a t h- ~ > r-~ «-» . — •— . — — — -J ^ ^ r— 1 s/ \^ r-l 00 00 00 OO X X o r— 1 UJ r— 1 o LU *-' _J _J _j _J r-^ _l —I r-l r-( m ••— — o ~— -_ o u. u_ u_ U_ — - «-* n O z> O II z> r— 1 vX ^ ^ ^ o ^ ^ O < o —' O o -H » — ( *-' o ►-< 1 — « o < < CO CO o o X 1— 1 o O X o X o ►— I >-- 1 —1 >— < o r— l '", O t— < 1— 1 r-t ■— < i—! r-l O o O o o O m >J- o t— 1 in m s0 s0 vO o vO CNI o o U> LJ (J> 138 CD < r- I -} CO LU cq o o o — *> 0 O "^ _J UJ 1— ( — < > «— » CO CrT O *-■» UJ h- _J •• CO *: Cl CO UJ — 21 0 > 1— UJ H- 4 X 1 h- CO < < — » 1 _J —i UJ UJ •~- X SI err H- h- < co 0. Cx. CO O < »- UJ V- _j D .<. O — UJ 1— 2 * D O _J < 1- --» X CrT UJ CO CM + < Q >- < \- CL Q X 0 CC CO Z 0 f—t 0 O _J < 2 m >— 1 CO 1 UJ 0 co < 0 LU t— 1 X X ,—1 X *l O »— K- w-i CM ^- + -J > t- 5^ O < < a: --» < _J O »— i,C •— < 0^ \ V. 0 -J IJ < O >i x: 2: O ^-» 0 v: O 2: *-- x: — - ^-> < UL rA CM »-- — - UJ 0 0 ^ 2: ^ 2 CO CO ^- 2: 2: • »-. — - Di i^ >- a — - «-. 1 1 — cc X < 0 ^ P UJ ^ Q UJ r-i .— 1 »-• --^ 1 UJ h- • «-~ i»f 0 X ~^ h- — ^ 4- — + _J -J 1—1 x 0. 0 0 i*T ^ t-H 1— _J LL 3 "> -) -> ~i ^ i^ t— cc O 1- X UJ Q cm: UJ t ±C u CO II 11 UJ Q ►-< 0- 21 < < CD cQ M M O • 11 UJ *-~ — CO ^^ _J II UJ 0 h- h- 1— I— X X 0 r— 1 UJ ,-H O UJ ■ — r-A O i~ _j r-( CM 1— II _J y; — . i-H UJ LU 2: 0 LL LL U_ UL ^ — • 11 O 3 O 11 IJ _j r-i LU cO ^ + ro II ^1 v: — ■ _J r-t D Z) h- * UJ UJ UJ UJ II II 0. in 2 \T\ CL 2" ^ r-i > 0 ■~- :^ 1—1 *r *-» J «— 21 ^ i— I 2 z 21 LU O O O O r-H CM 1— <\j K-* cm H- k— < ^- O cr: 21 m ^ O i^ _J n:; i— ct: ■^ O — < ►-1 or cc O O O O 1— h- _i O l~ O _J \- -j O UJ CrT X II 0 II ^ w 0 UJ _J a h- y~ U) II II II II C£ CtT UJ i~ 2 H- UJ Z. UJ k- CO UJ w- *£ (— X. »-< O 1— 1 X UJ h- Z 0— 1- 2 t— < cm f—i c\j d O 0 O O O O O 0 O CO X U- *: 0 XL k— CO CO f- a Ci a 0 LU < < < co CO 0 O X — c— ( O O CO X O X O 0 t- ►— < ^ 0 >^ X X X X X 0 l^ 0 O O .-1 1— I 1—1 t-H co 1— t CM ^-i r- f O O 0 O .-< ro m -H r-l sj- <\J r-4 in 0 r-« r-< O f-l C\< Csl (\J CM O t7> O 0000 o o o o 139 o ^•^ X X r-l O o + r-l 9- -J r- ■z. r— 1 CL UJ X r— * < X in s: a: X z O UJ «-- >- UJ X # Q X r- ■-> a ^~. r-l oo < '£. •» r-— X> — » (Nj UJ o — u_ LL o • r-l + *^ Q a: _J 1 — 1 on — X r- r\j _J — . < LL X r- r-l a: v. 5 ^~ r. QJ X. X ^ Z h- O 1— —i X 1— «~- •— •— > »-» < o r-H --- l—l r- -J — * Q a r-l o z o - H C UJ _J ^ O X + uo r-i •-H 00 (N O 2 o ^: r-» c* + _J UJ — -J X • o < X — r-l a. ^ ^ X) < ^ o (NJ r— + M "f X _j •— _) _i Wi — u_ M O H -~ X _J + •iC M < < 1- » — c •« a o X _J 1 i=£ «-~ — a: > »— t co <— X * — o ir: «-» •~- rH TVJ < X i— *k r— r-l o ^. » — t •— i— 1 _J + z cc r-l z X X »■ • o UJ _l + UJ _J >- Q o UJ r-l ». r-l f\l LU X r- UJ _J Q i^ C- o X l—l r- «• ■ « X i—t a :*c > r- — • r— 1 X r~ + »• o CL 0s r-l vQ + o o •• X — < r-l M •* ^^ r-i r— X a s: i^ »- LL a r-l r-H »— !NJ X »» 2. r-H -^ ♦* l—l in LU •• .-4 ► o « 5; o ii X X— o I— 1 >- o II i—i + •— r* i— 1— r-i X X * i— < « o o II — . II 11 • C * II r-. _J h- \ CiT — sT O -J z o • 1 r~t *-~ .~~ o II y — | X o 1—1 ii r-l ^ r— »• 3 II cc »■ o • > II o o -J + I— 1 r-l ii II II -J + o ^-» o o o_ X r-l o — Q -~ II II >i _J + + r— r-H 1 — . r-~ i^ _) t r- < 1 r"> 1— 1 1~ -0 -o M O X r-l C\J l—l —^ —~ \X _J _J UJ cc _J UJ r— 1 i^ UJ o X IJJ •I I— 1 Z •- ». r-l ii -£ LU »~- «— 1 r— 1 r-l ~— V^ v: X> rH r— I CO v: 3 «— l—l — 15 II r-l x. II x> o o ^^ < X CO o — ■^ •— h- _l — ■w^ c _l w^ ~- Z — r O r-l ■ — z rvl o N z --» O I— 1 — z l—l ■^^ H cc l—l --I — I— o — z> UJ Q t— f\J UJ f— a «— ■ M r-H m t— 4 CC C\J c^ K- H cc ro _J t— 1 o UJ < h- •" 0> LU < UJ M C_ o o 2: r- Q 2! a t- z CO II z h- < CO < t— l—l co 11 i^ 1— o I— SI X rvj i- s: X *- s > Q£ ►— < > >— 4 c£ 2 >■ > Z £0 cc z »— N— z \- >—" r-/ Q 1— r-l fV O LL o < a a. □ < Cl Cl a a o _J o o Q o Q o o o _J o □ c rv; o Z a. O Cd c Q — • o X X X o X X X o O X o ^ X o r-l O CO X o X o l—l o CM CC X Q i U <^} 140 •■ X ■— 1 »- X o t X tf> c — ~ r- CD . •• X 1—1 u. •—I ^ •— 1 »_» o UJ "^ •» a X X _J 2: DC X 1-4 * * * * cj UJ UJ «— • in * * * »— « > X >— t • * * * s: LU 1— — o * * * < _J M u. * * z z p* * * > UJ X > X * o * o U Z 9 a X i—4 * * UJ * * X UJ X « <\l * LU * t- 0C f— t ^* • * _l * 1— I LU «* *•— ( r- * a. * 3 L_ UJ 1— 1 21 u_ # * 21 O * 00 (V < :£ X * o * X Si UJ •—I * * 1— cc o X » * UJ * 0- Q » — i 1— CVJ * z * UJ oo X t * •—1 * Q o c X ^ r- u. * * 3 * Q o *» ■— 1 •s * o * DC r— 1 X «-» X * CiT * < »— < t— f— < * * H D o •* cd •» * Z * 1 Z t— > 1—4 ro # o * < < t~ oo • * » — « * s; CM l~ UJ ►— 1 X co * <_ * o ^-4 00 > z ». U- * * < -J * 00 CM St" r-4 O t— h- _j ►— c X * o * Sf l~ < < >J < 00 o t— 1 * c«: * o UJ O O t- CD 00 UJ X — * 00 (N * UJ # K- O — UJ DC 00 v. X • * i— * LJ CD — z> r- s •* •O * z * UJ ^- r— i _l _) X ♦< «-» U- fc >— t * _J —• + < < •— • OO ►—4 »• * * UJ ^ ^ > ►— * •* Z »■- X * X * oo i^ i£i X 1— CL < H 1— 1 * t- * ^4 ^^ «_ LT\ Z 5; a: X ft> * Cl >? u. o ■— ( 1— H- o UJ UJ t— •* r-l * UJ * □ ■4- in sJ- O CD •—1 t~ h- — • * o * 1— 1 •J- y 1— 1 >-H »• o o CO H- 4 •o * # 00 o a vO ^-^ 00 OO X Q_ X (—4 ^ LL * a * X V- t— rvj * * m T r- »• rvj ** * Oi * h~ O a «*■ • 1- 1— — - «■« H- o *■» f-4 X X # < * 0. o CD f-^ r-4 O -J o *N. Qf f X <— . sf * o * ^ UJ ^^ -— t t I— 1 •« O X r— 1 II o r. * z * •—1 o m ^-i II II ^- ^~ 0* o Cl .— 1 •> CM * < * f-l « • ^ _l •—I X 00 #- 21 ■W-H c-> x * l~ * r-4 LU 1- ^-: H- _J ^ *; ^ UJ o •• I— < y_ x «. r~l UJ UJ * oo * e> z _J CM 1 LU _J ^ ^ «_^ — D o o — r < 1— •» O o •** Z) Z> ft ifT o » — 1 • CO O '<) 1J t CJ o z o — ~ h- OT c. I— f\j — - t— z z * * -^ SI CNJ 5. st- s: z ro r—l ^-4 z z *— 1 CM UJ < t~ UJ TT 0> LD < iw-* >— 1 # * V UJ DC CL t — i r-4 (—4 ►— H 21 i—l ^( >— < >— * J— o ►— ^>_ c CM t— y l— h- # # * I— UJ z II O ii v- >— < ^ sf — 1 1— •— ( *— ■s» h- O DC o o o * a. * ci UJ II LL 2 o "SL CJ U_ CJ O LL U_ o 00 o c* LL 1— t v0 cm a CO o 12 LL, — o o o o o * * * ^ o _J —i ►— * o > — i Q Q * — * i — * r~< w~* 1— 1 r\j CM o O o o o 0" 0^ O o < <- rg r-l CM CM r-f .■-> o o o o o o o CJ o o + cd oo I 141 o z: < * ►— < z: < 00 + cd oo I I < in II 2 Q O —1 vj" •w~ CD -— — rH O t- ►— < z: ^~. vf t- o 00 z: ^-i O O »— 1 •» 4) 1- CD 00 LL o CO O — — - O i*; u_ o ~ vf *v «-' ^ «— 1—4 r—l -~- 00 UJ X — + r— 4 h- i— _J CD v£ o o (\i cd cd .-*. -— — i ^ * r— 4 1—4 • • r--J Is- — h- oo oo O o 1 r-4 v0 CJ u_ • • • • — . t i— 1 UJ UJ o o x> z: z: r—l •" -~ UJ «* \S Z — 1— o *— h- z z: >— * »— * - z: 2 CC k— . UJ -J I— < UJ to r> 1— 00 CL UJ Q_ DC 3 O J— O < o a: • UJ o a. o-i s: UJ u. h- o o O0 UJ T" i— 1— < a. _j UJ o O a. CL UJ UJ z: 1— ►—4 z: 21 H-4 a: • UJ » I— t UJ • o • D- Q. O O O • m u_ o oo z: o < O _i X C\J m x o CM o □ o CD f— ) r-l •• II • CO O h- r- x ^ _J ^ r-4 N^ « o — rn — h- i-t s: uj < r-i O •— h- 2 r^ ii — >-i q; _j u_ c£ o o _J »-i 3 U. D r—l rg r- -i o h- I— o o I- CD O — ■ CD — . r—l — + CD O O0 00 CD _J r— i r— r-l O r- v- o o I- CD o — CD -— — + CJ CD OO 00 o o o -> <-> >— Q t- X »• o CM (M • 00 LL X LA UJ Q X la X o CM II — Z X 2: cm — - t\i Z «-< Z ► ». UU ^ > z lu z _i — x oo r-~ a ► - x z o Z CM O o o o h- o ^-1 II II J .—< ~ CM i— I ro • ♦ M CO 1— LU ► r-l LL UJ J DO- r. ID . Z ■— I- X Z fM «-« uj < o >-* s: h- >— S •* I— «-h Z m or Q. Z — o a: o >: a a. O -^ U_ UJ O >-i r-l wri —i CVJ t-t ro o r- r- r- UJ a: < a: UJ 0- 5: LU Q Z < LU _l < > OO a z < >- < 00 a x h- cx LU O CM CM LA m o h~ a Q _J O X II « o — ' -> • ►— < »— J O r- • —* LO OO II LA O LO II O LA OO O O _J — h~ CM LL CX. UJ a x CO x o en ♦ — LL O - _J >- O y~ X >- >-* z I— _J CM »■ < t — O0 s0 C LL _J X •• o < X s >- X — CM M r-t o o m ro ro a. UJ o UJ X> ro II O o a u. o o x o x o -< o x _J o z >-* 3: CM LO in o LA LA or O LL m ro CO X o CC 10 h- < o: LU LLJ CL z 2: »— 1 UJ K i- X) O D a: Z < X < I s h- a. _j UJ < Q 00 00 2£ i— a > — i oi LL O z O < _J a > X !— KH K— 1 z 9 *—4 s*L — 1 < < 00 c _J s: 3 3 X s: *~ i 00 z LU «— i c£ s >— 1 X3 LL o a LU a: z a LU i— i z i— > — * < V- z _J t-H □ s or 2^ LU 00 h- >-< LU X O H O O L> O O O t_) o o o o <\J 143 o a. UJ o x m «->. »~ lO < CC UJ to \- or UJ UJ s: t— f~+ LU ■— I s: «"* r- ►— < •» X •— (\i «fr M • <\j 1 in *>> u. •« ' — 51 jS X M 0C o o — UJ -J .—1 * X U-' •* -— t- co \ -~~ o •* •~ (/) to m ►—I r-H r-H • >— r- r- O s: U- s: 1 UJ Di •>. a: .-^ c UJ >- UJ r-t X -— h- X 1 f\J r- UJ »•— « r- ►— < (NJ o C£ 2 D •>— vo o *- < -~ U0 t- U. ►— 1 t- _l <\J ►— i w o tn < • ^ o »— i tO vO O ^^ X UJ «— u. UJ o t- Q C\J ro i~ Z t* o in n0 r~ • Cl 'v — i O r- «—< in LT\ ir\ C\l UJ (\j I— V- 00 21 C\J in LO in CM o (N o o z X r\ O o o 1 X _i_ o o »-H CM H- y- 1— ^-^ m in — • .~ s: r-l U- O o o. r-l (NJ (M UJ - ^ ^ UJ fc-H (NJ (M OJ «-- ^-. \ k- H ■^ o *• h- k- r~. to ** UJ Ci r- « • 9 — CNJ •• ^>. •• -— X O 1— t _J -— o >— 1 — o h- r-H 1— O h- 1 m o r- • r-H _J t 1— < • •" vt" X X UJ II o UJ _J —~ ol X cc X z «— O II — « — - CO o i—i UJ r> r-l m z »— < t • • UJ r-< •• r-H •« r-H a UJ M X r-H M 2 tO ii X) o — H »— 4 ^-~ »-, — . X5 1 CO .— . o o — - ►-< 1^ II II V-H «— II r— « II LU -^" — 1— «- s: in ►-H 1— t t—i z r^ » — I in r-H •>— 1— cc ~— (■- i- ^ 2 h- r~ < O >— r— r— 4 _ H- o Y- z >-H a; r-H f- ^-> to« — z h- II h- II r-l oi H- 1 — 1 CC 00 z 51 \~ O U- o s: U_ o i— tO CJ CC O •> LU o u. u. u. o O H o h- :•' O a CC o a D OO Q r-H o o CM r— ( o to CO r-H ZK r-H O o r — 1 ►-* u in in o D in LD Q in in CO LP in U- r\j m ro o CC U. CO 00 r-H o CC CC o o o o o 144 * * * * cC * * o * * 1- * * o a: or < UJ UJ u_ »- y- < < > 3 3: 1- 1— H O a > ,— . Z z t*— i • < < 't- C\l X X i— o X a * h- X z ►—i U- o o «— LU *-H o >- -J a: .— O r-l * * ar * C\J O * >? a ro O CC * * u_ < cc O * * ro O K- * * s i— ( O in + y- o X X < o 1 o o o o o a: -~ 1 UJ I --~ o — <\J (\J o ► — i UJ f~i UJ »— < •— . -4" r» •» o •* ^~ vC o r\j ~-- o • X X a: V- o CO in CO i— t sO o o Q- «— in r\j CO r- * O ro -^ ro — . CO cc > oj ro ro in r\j in • CM r- vt" •- X a£ — o r\i CO < t— ( LLI r~\ o o o 00 X r- o r- >t t O 00 X CO ~x_ o z cr m O 4- > 1— • •» r-4 •» r-4 UJ z z o Cx.' • vO _j _J Q o — - CO o — X o a a ►— * ft o m ^-( o t _J — ' (~ cc «— V- z o ►— 4 »— i 00 O i O > X w- «.,- » — 1 XL 1— ►—( c£ z r-- o a Z X z jr _J a: r- LL U. &. O o C£ a o o k- z x> CO X >— i ^i (N ro O X IU >-H •— < ~x U. CD I£ U- o O w uj u_ u_ O < < < o_ o Oi o o c\i i— I «4" CO in »~ evj o o O CO o U- o CO CO CO CC in CQ a: »— t o o o o O O O t'S- 145 o o o o m o in CNJ o o CM m o o o in o ro o o in in ro oj r-t o • % m o o O o r-l C\J r-l .--i cnj CM r-t r-l vf r-l r- 1 rA CNJ OJ r-< r-t r-l r-l CNJ CNJ OJ O «— 1 • O o O o o O o O o 1 c O o O o O O O O o O o o rO UJ UJ UJ UJ UJ UJ LU UJ UJ UJ UJ UJ UJ UJ UJ UJ UJ UJ UJ UJ UJ UJ • in CO CO CM OJ CNJ o CNJ uo r- CNJ OJ r-t o o r- CT^ uo h- co r- m O O ro ro r\j >t r-l f—( CC t 0> sf CO CO in r- >3~ r— r- o co m CO r- in in CC r- Osl CNJ ro CO »J- r-t r-t ro f^ CNj ro V?" r- r- vf LO ro vt" cc r-l in CC CO \ 0> r- ro CO in O ro o CO ro in h- ce O « « o c f> i— i m CO ro ro o CC r- Cj^ CC r-t o o CC in c* 'i—i r— 1 ro oj rvj o O • » r- r-t ro vO CNJ O CNJ in VT «— t CNJ CO CO rA r-l CO cc CO o i— 1 r-l -* vt LO o IT\ o o ro O o i o o 1 o 1 o o 1 o o o o 1 o o O 1 o 1 o 1 O i o 1 o 1 o 1 O 1 o o 1 1 O o 1 i i 1 1 1 1 1 1 1 1 1 1 1 i 1 1 1 1 1 1 • • « « o o vO o ro o co ro r-t o o ro ro ro ro ro ro ro ro r0 ro CNJ CNJ CNJ CNJ CNJ OJ CNJ CNJ CNJ OJ ro ro • t o o O o o o O o O o o O O O O o o o o O o o • * r- m o o ro ,~i UJ UJ UJ UJ UJ UJ UJ UJ UJ UJ UJ UJ Ul UJ UJ UJ LU UJ UJ UJ UJ UJ CNJ o in r- r— I n?- r\i C\J C' r— i o co in o o CNJ Is- o r- CO a ro o r- r- o o rv r>~i in ■—I r-t r-t o rvj o vO in o in o o r-t r— CC o r~ O s0 « • o co o r-t CO CC CO vf o cc ro r- l—l o o ro m o r-l o O o OJ rO r~ r- r-l c* ■4" co ro t • ro oj r- in in O o o CC r- 1 o ro CNJ CNJ r-l CNJ o o r- • in r-t r-l (\i rO o * ?■ in m o r- CC r-l i— 1 ro CM O O O O o o 1 O O o O o o O o o o rr o o o O O < • o o o o 1 1 1 1 1 »~ O • • < in o o Q vf ro <& I< 146 REFERENCES Adams, R. M., Depth of the motionless layer in the Gulf of Mexico. The A. & M. College of Texas, Dept . of Oceanography, Unpubl. Tech. Rept. 11. UNPUBLISHED. 1954. Austin, G. B., Jr., Some recent oceanographic surveys of the Gulf of Mexico. Trans. Amer. Geophys. Un . , 36(5): 885-892. 1955. Brown, N. L., A proposed in situ salinity sensing system. Marine Sciences Instrumentation, Vol . 2_. Inst. Soc . Amer., Plenum Press, New York, 19-24. 1963. , An _in situ salinometer for use in the deep ocean. Pre- print No. 8.2-3-64, Inst. Soc. Amer., Pittsburg, 11 pp. 1964. Brown, N. L. and B. V. Hamon, An inductive salinometer. Deep-Sea Res., 8(1): 65-75. 1961. Cochrane, J. D., Investigations of the Yucatan Current. In unpubl. rept. of Dept. of Oceanography & Meteorology, The A. & M. College of Texas, Ref. 61-15F. 1961. , Investigations of the Yucatan Current. In unpubl. rept. of Dept. of Oceanography & Meteorology, Texas A&M University, Ref. 62-14A. 1962. , Yucatan Current. In unpubl. rept. of Dept. of Oceano- graphy & Meteorology, Texas A&M University, Ref. 63-18A. 1963. , The Yucatan Current and Equatorial Currents of the west- ern Atlantic. In unpubl. rept. of Dept. of Oceanography & Meteorology, Texas ASM University, Ref. 65-17T. 1965. , The Yucatan Current, Upwelling off Northeastern Yucatan, and Currents and Waters of Western Equatorial Atlantic. In unpubl. rept. of Dept. of Oceanography & Meteorology, Texas A&M University, Ref. 66-23T. 1966. Chew, F., On the offshore circulation and a convergence mechanism in the Red Tide region off the West Coast of Florida. Trans. Amer, Geophys. Un . , 36(6): 963-974. 1955. Defant, A., Physical Oceanography, Vol. 1. Pergamjjbn Press, London. 729 pp. 1961. Dietrich, G., Das Amerikanische Mittlemeer. Gesellsch. f_. Erdkunde zu Berlin, Zeitschr. , 108-130. 1939. 147 Froberg, C.-E., Introduction to Numerical Analysis. Addison-Wesley Pub. Co., Inc., Reading, Mass., 340 pp. 1965. Gaul, R.D., R. E. Boykin, and D. E. Letzring, Northeast Gulf of Mexico Hydrographic Survey Data Collected in 1965. In. unpubl. rept . of Dept. of Oceanography & Meteorology, Texas A&M Univer- sity, Ref. 66-8T. 1966. Gaul, R.D., Circulation over the Continental Margin of the Northeast Gulf of Mexico. Ph. D. Dissertation, Dept. of Oceanography, Texas A&M University, January, 1967. UNPUBLISHED. 1967. Hamon, B. V. and N. L. Brown, A temperature-chlorinity-depth recorder for use at sea. J. Sci. Inst. , 35: 452-458. 1958. Ichiye, T., Circulation and water mass distribution in the Gulf of Mexico. Geofisica Internacional, 2(3) : 47-76. 1962. Knudsen, M. , Hydrographical tables. Copenhagen, G.E.C. Gad., 63 pp. 1901. Lafond, E. C, Processing Oceanographic Data, H_. 0_. Pub . No. 614. U.S. Navy Hydrographic Office, Wash., D.C., 114 pp. 1951. Leipper, D. F. , Nature of ocean currents in the Gulf of Mexico. Tex. Jour, of Sci. , 2(1): 41-44. 1951. , Physical oceanography of the Gulf of Mexico. Fish. Bull. No. 89, U.S. Fish and Wildlife Service, 55_: 119-137. 1954. , Sea Temperature for Synoptic Oceanography and Sea-Air Interaction. In_ unpubl. rept. of Dept. of Oceanography & Meteorology, Texas A&M University, Ref. 66-23T. 1966. , A sequence of current patterns in the Gulf of Mexico In Oceanography Abstracts, Trans . Amer . Geophys. Un. , 48(1) : 130-131. 1967. McLellan, H. J., The waters of the Gulf of Mexico as observed in 1958 and 1959. The A. & M. College of Texas, Dept. of Oceanography & Meteorology, Ref. 60-14T. UNPUBLISHED. 1960 , Elements of Physical Oceanography. Pergamon Press, New York, 146 pp. 1965. McLellan, H. J. and W. D. Nowlin, The waters of the Gulf of Mexico as observed in February and March 1962. The A. & M. College of Texas, Dept. of Oceanography & Meteor., Ref. 62-16D. UNPUBLISH- ED. 1962. 148 McLellan, H. J. and W. D. Nowlin, Some features of the deep water in the Gulf of Mexico. J. Mar. Res. , 21(3): 233-245. 1963. Metcalf, W. G., Oceanographic data from the Caribbean Sea CRAWFORD Cruise 17. Woods Hole Oceanographic Institution, Ref. 59-9 (Apr. 1955). UNPUBLISHED. Nowlin, W. D. and H. J. McLellan, A winter characterization of the waters of the Gulf of Mexico. J. Mar. Res. , 25_(1) : 29-59. 1967, Ostle, B., Statistics in Research, Rev. 2nd Ed . Iowa St. Univ. Press, Ames, Iowa, 585 pp. 1963. Parr, A. E., Report on hydrographic observations in the Gulf of Mexico and adjacent straits made during the Yale Oceanographic Expedition of the MABEL TAYLOR in 1932. Bull. Bingham Oceano- graphy Coll. , 5.(1): 1-92. 1935a. , Hydrographic relations between the so-called Gulf Stream and the Gulf of Mexico. Trans . Amer. Geophys . Un. , 16th Annual Meeting, pp. 246-250. 1935b. , Report on hydrographic observations at a series of anchor stations across the Straits of Florida. Bull . Bingham Oceanogr. Coll., 6.(3): 1-62. 1937a. , A contribution to the hydrography of the Caribbean and Cayman Seas. Bull. Bingham Oceanogr. Coll., 5.(4): 1-110. 1937b. , Further observations on the hydrography of the Eastern Caribbean and adjacent Atlantic waters. Bull. Bingham Oceano- graphy Coll. , 6(4): 1-29. 1938. Stockman, W. B., A theory of T-S curves as a method for studying the mixing of water masses in the sea. J.. Mar. Res . , 6.(1): 1-24. 1946. Sverdrup, H. U. , Zum Berechnung der Druck und Massenverteilung in Meere. Geofys. Pub., v. 10, no. 1, 9 pp., Oslo. 1933. Sverdrup, H. U. , M. W. Johnson, and R. H. Fleming, The Oceans; Their Physics , Chemistry, and General Biology. Prentice-Hall, Englewood Cliffs, New Jersey. 1087 pp. 1942. Wennekens , M. P., Water mass properties of the Straits of Florida and related waters. Bull. Mar. Sci. Gulf and Caribbean, 9.(1): 1-52. 1959. Wust , G . , Stratification and Circulation in the Antillean-Caribbean Basins, Pt. 1. Columbia Univ. Press, N.Y. 201 pp. 1964. 2k Thesis B5433 Birchett Temperature -sal- inity relationships in the surface layers of the east ern Gulf of Mexico in August, 1966. Thesis B5433 7>J •^ Jl±MJ 1 Birchett Temperature-sal- inity relationships in the surface layers of the east- ern Gulf of Mexico in August, 1966. thesBb433 Temperature-salinity relationships in th 3 2768 002 13472 8 DUDLEY KNOX LIBRARY