N 60° 50° 40° 30° 20° 10° 

 

 D 

 (m) 



I 



20° 30° 40" 50° 60° S 



- J ' ' ' ' |0 



D 

 (m) 



1000 



1000 



-1000 



2000 



2000 



-2000 



30001^ 



3000 



-3000 



Figure 2, Average depth, D, of the layer of no motion in the Atlantic Ocean. 

 The curves « » — — represent D (<f) ■ const, sin cp , and the 

 values according to A. Defant (19lil) are indicated by circles (0). 



or, the relative variation of D is given by 

 where R is the radius of the earth. Since 



f % = R ctn * ' 



there is much evidence that in the "gross" features of the oceanic 

 circulation 



and the important term 



tit 1 §R\ &t 



\o)y D Oj) 0x 

 in equation (11) drops out in the "gross" features of a model where 

 only zonal conditions are considered. 



In the model by Stommel (194-8), Hidaka (1949) and Munk (1950) 



15 



