Analysis of Data . The available sea surface temperatures 

 were, for the most part, averaged for each 1 -degree quad- 

 rangle of latitude and longitude. In the areas where the hori- 

 zontal temperature gradients were small, the sea surface 

 temperatures were averaged for 5-degree quadrangles. The 

 main objectives were to determine the geographical dis- 

 tribution of surface temperature and to locate the Antarctic 

 Convergence. Therefore, in areas where the gradients were 

 large, the sea surface temperatures were not averaged, as 

 the averaging process might have eliminated the large gradi- 

 ents indicative of the convergence. The average values were 

 then plotted on a chart showing the bottom configuration so 

 the influence of the topography on the distribution of the 

 isotherms could be studied. 



Whole-degree isotherms were drawn, using the above- 

 described temperature plots. Sufficient data were available 

 to construct isotherms from only -1 degree C. to 3 degrees C. 

 (see fig. 12). In areas where data were lacking from Operation 

 HIGHJUMP (see fig. 2), the location of the isotherms was 

 determined by using data from the Discovery Reports * and 

 then considering the probable effect of the bottom topography 

 on the pattern of the isotherms. 



90* 



FIGURE 12. Sea surface isotherms. 



140 150 160 170' 180 170 160 



150 140 



23 



