17 

 I 



10 

 I 



15 

 f 



_r>ufrgested looQtlonn 

 of B.T. statlone 

 relative to wind 

 field (curve i; ) 



(3/2)L 



->-x 



(d/dx)v 



Figure 18. Hypothetical Wind Distribution and Consequent Divergence. 



Thus it is reasonable to conclude that the thickness of the ECC water 

 mass is caused primarily by varying wind and that the positions of the 

 BT stations relative to the southerly winds are as suggested in Figure 18. 



While it is doubtful that the geostrophic relation will hold for this region 

 more than very approximately because of the certain existence of frictional 

 and inertial forces, no other approach is possible with the present data. 

 Nevertheless, use of the hydrostatic and geostrophic relations suggests a 

 current pattern that is consistent with that of the surface temperatures. 

 The probable current directions are indicated by arrows in Figure 15. 



The thermocline depth, defined as the depth of the top of the layer of 

 rapid temperature change, is given in Figure 20; this presentation does 

 not show the deep upwelling evident between stations 15 and 16 in Figure 

 17. 



Saiango 



Four BT lowerings were made at nearly the same station at Lat. 1°22' 

 S., and Long. 80°59' W., 15 n. miles NNW of Isla La Plata. Two charact- 

 eristics are common to the 5 lowerings: The first is the small cool layer 

 some 20 to 40 feet deep overlying a warmer and thicker layer; the second 

 is the very sharp thermocline, the temperature decreasing from 75 to 76° 

 F to the neighborhood of 60° F in some 30 feet or less. The cool thin 

 layer is most probably due to the cold southwesterly wind observed blowing 

 in Beaufort force 3-4 at that time. The sharp thermocline separates the 



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