The final averaged values of the layer depth were contoured 

 as shown in figure 18. On the basis of the theory outlined 

 above, arrows have been entered on the figure paralleling 

 the contour lines and indicating the direction of the flow. The 

 surface current field as thus indicated agrees well with the 

 current field presented in other studies of the antarctic. The 

 trend of the lines of equal layer depth is practically the same 

 as that of the isotherms, indicating that there is little flow 

 across the isotherms. This procedure of deriving surface 

 currents assumes that the salinity effect in the surface layer 

 is small and that the major flow is above the thermocline. 

 In this region these assumptions are sufficiently accurate to 

 give the direction of the surface flow, but uncertainty remains 

 as to the use of this method to obtain current speed. 



The location of the boundary between currents which 

 flow in. opposite directions should be the location of the mini- 

 mum layer depth. From figure 18, showing the topography 

 of the layer depth, it is thus seen that there should be a general 

 easterly setting flow north of the area of 30 meters layer 

 depth and a westerly setting flow south of it. 



The slope of the discontinuity surface for the easterly 

 flowing current is on the average 0.058 meter per kilometer. 

 This means that the boundary surface sinks 0.058 meter with 

 each kilometer toward the north. For the westward current, 

 the boundary surface sinks on the average 0.055 meter with 

 each kilometer toward the south. 



35 



