BATHTPELAGIC SQUID BATHYTEUTHIS 



107 



The major portion of the Antarctic Circumpolar Water is between 

 0.5° and 2° C. The 1.5° isotherm penetrates to 58°S as an 800-1000 

 meter thick layer between depths of 250 and 1300 m; north of 52°S 

 the isotlierm dips sharply into Deep Water. The 2° isotherm ascends 

 vertically (in the section) from over 2500 m to the surface in the con- 

 vergence zone. Two cores of 2° C and slightly warmer water occur be- 

 tween 48°30' and 51°30'S and between 53°30' and 56°S; the larger, 

 more northerly core exists between 400 and 1500 m and the smaller core 

 occupies a thin layer between 350 and 600 m. In summer the northern 

 core, and perhaps the southern core, merges with the 2° isotherm so 

 that continuous 2° C water extends farther southward than in winter. 

 The salinity section (fig. 24) shows the submergence of low salinity 

 Surface Water between 48° and 50°S. The isohalines through 34.60%o 

 originate in shallow water in the south ; they gradually descend north- 

 ward until, beneath the convergence, they dip more sharply into deeper 

 water. At 46°S the 34.60%o isohaline lies at 1500 m. South of 60°S all 

 salinities are below 34.70%o. The major portion of the section shows a 

 complexity of isohalines outlined by the 34.70%o line. This envelops the 



Figure 24. — Vertical section, 35°W, 46°-62°S; salinity°/oo, sigma-t. Capture points of 



Baihyteuthis abyssicola. 

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