160 



where 



Thermohaline Features 



If — > 



Iiiy) = -g {fp^ - curl T ) dx, 



1 f'- 



i2iy)=-n\ fpwdx. 



(22) 

 (23) 



WIND-DRIVEN AND THERMOHALINE CIRCULATIONS 

 IN A RECTANGULAR OCEAN 



In order to portray some of the chief features of the thermohahne circu- 

 lation, the analjiiic solution for a simple rectangular basin has been ob- 

 tained. Coasts are placed at a; = 0, a; = r, and ?/ = 0, but the ocean is left open 



TOTAL TRANSPORT IO»M'/SEC 



Fig. 78. A rectangular ocean with an idealized thermohaline process. The 

 vertically integrated transports per unit width in the interior (or central) 

 regions of the ocean are shown on the x, y plane at the right of the figure. The 

 broken-line arrows show magnitude and direction of the vertically integrated 

 transport per unit width due to wind stress alone. Wlien the idealized vertical 

 mass flux is introduced, new patterns of flow appear; the heavy solid arrows 

 indicate the transport per unit width of the upper layer, the fine solid arrows 

 indicate that of the lower layer. To the left are shown the total transport 

 functions of the western currents. 



on the northern edge. A wind stress of the form Tj. = — Tq cos ly is applied 

 to the surface, and a vertical flux oipw^ =pwQ cos ly is fixed at the level of no 

 horizontal divergence. The values used in computing the transports ex- 

 hibited in fig. 78 were : r = tt/Z = 6000 km. ; Tq = 3 dynes/cm.^ (this fairly large 

 figure for the surface stress is used to bring the curl Sity = 7r/2Z up to Munk's 

 value of 0-7 X 10~^ g./sec./sec. and to include the 1-3 meridional factor); 

 Wq=10-* cm./sec; /? = 2 x 10~^^/cm./sec.; a.ndf=j3y. Detail of the western 

 currents is not shown, but the total transport of the western current in each 



