When actual observed values of surface temperatures 

 are plotted in the above fashion, erratic variations of the 

 surface temperature complicate the picture considerably 

 (see fig. 14). The more observations available, the more 

 complex the surface temperature fluctuations appear. They 

 are related to the variations in the meteorological conditions, 

 currents, and melting ice, as well as to the convergence 

 circulation. However, in each section the characteristic 

 break in temperature is easily discernible. 



Cross section A was taken during late December along a 

 north-south line which closely followed the 100°W meridian. 

 The sharp break in slope of the surface temperature plot is 

 apparent at about 6l°47'S with a mean temperature of 3.2 de- 

 grees C. on the steepest part of the slope (see table 7). This 

 is a higher temperature than was observed at the convergence 

 on any of the other sections. The surface temperature de- 

 creases about 2.2 degrees C. in a distance of 20 miles. 



55° 56° 57° 58° 59° 60° 61° 62° 63° 64" 65° 



67= 68° 69° S. 



-w 





y\y\ 



1 1 . 1 



i i 



- 





\ ^SECTION 



A 





V 



/I 



-■■■;: -A \ A "\ 



\ 



\ x ~-"'>-,„ 



1 

 1 



'' j^- SECTION C-3 



_ 



- 





| SECTION C-l ' 

 1 



SECTION B "• \ j V ,-\ 



' V 



Nil ' ^ v> y SECTION C2 



- 



- 





\ >.i w-sVc. 











\ V W 





- 







r ikVn /7s 



- 





1 



1(1-1 



\ .-. y,vi N \ a \\ v -- 



%rA> j -< If v 



i i i i i i 



i 



FIGURE 14. Surface temperature sections across the Antarctic Convergence. 



27 



