40° W 



ZCW 



eo^N 



50»N 



Transformation 

 Zone 



40* W 



20»W 



60" N 



50»N 



60" N 



50"»N 



40"W 



20 "W 



SAF-I 



Transformation 

 Zone 



60»N 



50»N 



40'W 



20"W 



B 



FiQUBE 32. Bubnov's 1968 scheme of the subarctic frontal zone on the surface of the 

 ocean in the spring (A) and in the autumn (B) of 1958. 

 Water masses: A — Arctic; SA — Subarctic; CNA — Central North Atlantic 

 Fronts: AF— Arctic; SAF-I— Primary Subarctic; SAF-II— Secondary 

 Subarctic 

 Formation centers of the Subarctic Intermediate Waters are cross-hatched. 



19 



