12 



INTERNATIONAL ASPECTS OF OCEANOGRAPHY 



ATLANTIC OCEAN: HORIZONTAL DISTRIBUTION OF TEMPERATURE, SALINITY AND 



DENSITY, AT STANDARD DEPTHS' 



By GEORG WtJST 



Inslilul fur Meereskunde, Berlin, Germany 



Plates 4, 5, 6, 7, 8 



1. The Source Material 



In an endeavor to indicate the thermohaline 

 constitution of the oceans in relation to the deep 

 circulation of the water masses, the procedure is 

 not by presenting the data in horizontal and vertical 

 sections but by presenting them as curved surfaces 

 which correspond to the contours of the core layers 

 (Kernschichten) of the stratospheric water bodies. 

 After having first achieved in this way a representa- 

 tion in space of the extension and the mixing of the 

 core water masses, we are prepared for a complete 

 understanding of the horizontal distribution of 

 temperature, salinity, and density at standard 

 depths. Therefore, the construction of the charts, 

 with which the work originally began, is placed at 

 the end of our investigation. The first fundamental 

 preparation for this goes back to A. Merz himself, 

 who, before the expedition, had planned (after 1922) 

 a card catalogue of all hydrographic observations 

 in the three oceans after the dates of the Challen- 

 ger and Gazelle expeditions; and for the Atlantic 

 Ocean had completed it for the condition of research 

 up to the beginning of the Meteor expedition. 

 A. Merz- has reported in detail in another place on 

 the initiation of the card catalogue, with the 

 preparation of which at that time Doctor H. H. F. 

 Meyer was especially entrusted, and on the point of 

 view, which fixed the method for obtaining values 

 at standard depths. After the end of the expedition 

 the author has carried forward along the lines 

 laid down by Merz the card catalogue for the 

 Atlantic ocean, concerning which more detailed 

 information is given in volume 4 of this work, pp. 7 

 et seq. Work on the exhaustive collection of all 

 available, uniformly reduced, and prepared observa- 

 tional material took, as a result of the greatly 

 increased number of deep-sea investigations since 

 the Meteor Expedition, so extensive a scope that 

 it could be handled only by a series of cooperators, 



' Translated by T. VVayland Vaughan from "Schichtung 

 und Zirkulation des Atlantischen Ozeans," Zweite Liefer- 

 ung "die Stratosphiire." VVissensch. Ergeb. der Deutsehen 

 Atlantischen Expedition auf dem Forsehungs und Ver- 

 messungssehiff Meteor 1925-1927, Vol. 6, 1st Ft., pp. 224- 

 233, 248-251, Beilagen 32-35, 1935. 



^Preus. Akad. Wissensch. Phys.-Math. KI., Ber., 1925, 

 vol. 31, p. 58. 



of whom special mention should here be made of 

 Doctor G. Bohnecke, Doctor G. Dietrich, Doctor 

 H. H. F. Meyer, and the technical as.sistants. Misses 

 M. A.sche, J. Peter, and J. Zietz. The number of 

 the stations recorded in the card catalogue soon 

 exceeded 10,000. In order not to jeopardize the 

 execution of the Merz plan to represent the constitu- 

 tion of the oceans on charts of oceanographic factors, 

 the author next eliminated all of the shelf regions 

 and adjacent seas except the Caribbean Sea, and 

 devoted attention only to stations exceeding 200 

 meters in depth in the open Atlantic Ocean. For 

 the open Atlantic Ocean the northern limit was 

 taken as the 65th degree of latitude at the Faroe- 

 Shetland Swell ; the limit for the Pacific Ocean was 

 fLxed at the 70th meridian of west longitude; and 

 that for the Indian Ocean at the 35th meridian of 

 ea.st longitude. 



After the exclusion of the stations for which there 

 are only bottom observations, the results obtained 

 from a study of those that exceed 4,000 meters in 

 depth are presented elsewhere,' and after the elimi- 

 nation of all defective series, there remain a total 

 of 3,440 stations with serial measurement of tem- 

 perature and about 3,100 with simultaneous serial 

 measurements of salinity, executed by about 70 

 research vessels in the years between 1873 and 1934. 

 For each station large scale vertical curves of tem- 

 perature and salinity were constructed. When 

 necessary the results of the different expeditions 

 were uniformly reduced to depths in meters, tem- 

 peratures to degrees centigrade, and, salinities were 

 reported in conformity to Knudsen's hydrographic 

 tables. The values for salinity were, when it 

 appeared necessary, recalculated^ and tested by the 

 correlation Temperature and Salinity in order to 

 recognize those of defective values, and to calculate 

 the corresponding salinity for the intermediate 

 depths in which there were only temperature data. 

 The vertical curves were, in so far as possible, laid 

 out in geographical order so that in working up the 

 series comparisons could be made between neigh- 



' This volume, 1st Lieferung. 



* For example for the Challenger and other series 

 compare: L. Moller: Zur Kritik und Aufbereitung der 

 Dichte- und Salzgehaltswerte iilterer Expeditionen: Veroff. 

 Inst. f. Meereskde., Reihe A, H. 15, Berlin 1926. 



