b. Salinity- 

 Salinity distribution was uniform across Bransfield Strait 



and varied only slightly, approximately 1.00 %> vertically to the depths 

 sampled. Prom low surface values caused by summer ice melt to a depth 

 of about 150 meters, maximum salinity changes occurred. Below this 

 depth, salinities changed little, about 0.05 %<>, to the lowest depth 

 sampled. 



c. Density 



The configuration of the isopycnals closely followed the 

 isohalines, both horizontally and with depth. Densities increased from 

 26.90 at the surface to as high as 27.85 at the deepest observation. 



d. Oxygen 



A high surface value of dissolved oxygen, 7*17 ml/l, was 

 observed at station 20. Below the surface, values varied from about 

 7.00 to 4.75 ml/l at maximum sampling depths on stations 18 and 19. At 

 station 20, the 4.75 ml/l oxygen isoline was at 230 meters and dipped 

 to 660 meters at station 19» Station 18 shows cells of lower oxygen 

 at approximately 75 snd 300 meters depth. 



2. Drake Passage (Figure 11 ) 



a. Temperature 



This is an excellent cross section of temperature from 

 Antarctic into Subantarctic regions crossing the Antarctic Convergence. 

 The Convergence is readily apparent between stations 28 and 29, where 

 surface values increased more than 3°C within a very short distance 

 (approximately 15 nm). In this zone, the cold water from the Antarctic 

 surface layer sinks beneath the considerably warmer and less dense 

 waters from the north to form the well-defined Antarctic Intermediate 

 Water Mass. 



The rise of deep, warm water from the north is shown by the 2° 

 isotherm. This water continues southward, forming the Antarctic 

 Circumpolar Water, between 400 and 700 meters, with maximum temperatures 

 at about 500 meters. Below the Circumpolar Water, temperatures gradu- 

 ally decreased with depth in a transition zone. The very cold and deep 

 Antarctic Bottom Water was not reached. 



b. Salinity 



From the southernmost station northward, the layer of 

 Antarctic Surface Water, with salinities less than 34.00 &, increased 

 in depth from 50 to 200 meters just south of the Convergence. In the 



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