The Stratospheric Circulation 



671 



In the deep layers the salinity distribution indicates a deep flow from north to south 

 between 1800 and 3200 m and, beyond 40° S, gradually rising to 1000 m, while in the 

 far south just off the Antarctic continent the cold Antarctic water sinks to the bottom 

 layers of the ocean. The following sections of this chapter are devoted to these 

 processes. 



Inside the water masses south of the convergence there is thus found in the upper 

 layers a vertical circulation that extends down to about 1000 m which occurs in an 

 anticlockwise sense when looking towards east. The uppermost layers are carried 

 northwards by the wind, sink down at the Antarctic convergence and form the main 

 constituent of the subantarctic intermediate current. Part of this water mass, however, 

 mixes with deep water and returns southwards in the Antarctic circumpolar ocean as 

 a warmer intermediate current. The top layers of sub-Antarctic water are rich in plant 



675 



1000 



20CHD 



3000 



36° 38° 40° 42° 44° 46° 48° 50° 52° 54° 56° 

 675 673 671 668 666 663 661 



1000 



2000 



3000 



Fig. 317. Distribution of temperature (upper picture) and of salinity (lower picture) in a 

 vertical section at 30° W. from 34° S. to 58° S. in the South Atlantic Ocean (series measure- 

 ments of the "Discovery 11", end of April 1931, according to Sverdrup). 



