the troijgh in the bottom. 



Survey #2, 27-29 July 1955. Fig u res 7-10. 



The waters of the Gulf warmed considerably since March, and were greater 

 than 27°C at the surface and wanner than 18 at 50 m. It is evident that the 

 coldest water reached farthest into the Gulf along the trough in the western 

 side. The isotherm pattern ceui be interpreted as indicative of a general 

 counterclockwise circulation near the surface, as was reported by Wooster (1959), 

 Survey #3, 28-30 November 1955. Figures 11-14. 



Warm water still persisted throughout the Gulf of Panama at the time of 

 this survey. Warming progressed so that the temperatures at 50 m were in the 

 range of 19**-24°C, compared to 15 -16 in March. 

 Survey #4, 5-6 April 1956. Figures 15-17. 



The area west of the Archipelago de las Perlas was cooler than that to 

 the east of these islands due to upwelling of cooler waters at the Bay of Pa- 

 nama. The period in which this cruise was made followed the time of strongest 

 northerly winds of the season. A second location of upwelling is indicated 

 near San Miguel Bay. 



The "double" upwelling period reported by Schaefer, Bishop and Howard 

 (1958) and by Forsber^ (1963) is not reflected in the present data, because 

 of the short time over which these observations were made. 

 Survey i^, 4-5 September 1956. Figures 18-22. 



Temperatures in the upper 10 m over most of the Gulf were at least 28 C 

 at the time of this survey. In the 25-50 m depth range, temperatures had 

 warmed to 18-27''c, and were 15-16 C at 75 m. The cold water entering along 

 the deepest portion of the Gulf is indicated by the isotherm patterns at 50 

 and 75 m. One also notes that the warm water reached greater depths in the 

 eastern half of the Gulf. 



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