All-101 yh 



gradient for the case of a steady wind having this mean distri- 

 bution. If we now have a time-dependent wind, we will have 

 non-vanishing pressure gradients in the bottom layer as a result 

 of changes in the free surface shape. The resultant velocities 

 in the bottom layer will tend to be uniform vertically (except 

 as influenced by friction) provided the bottom layer has fairly 

 uniform density so that the pressure gradient is independent of 

 depth. 



Suppose we have a two-layer ocean and integrate over the 

 top layer only* If we make use of the assumption of a station- 

 ary thermocline, and if the effect of friction at the thermo- 

 cline on the transport in the top layer is negligible, then the 

 resulting transport equations are essentially the same as those 

 attained in Problem 1. Hence, the distribution of mass trans- 

 port obtained in Problem 1 may be expected to be valid now, 

 provided it is Interpreted as the distributions of transport 

 above the thermocline. Since this is the transport usually 

 measured, we may still hope that the results are useful, 



6, Conclusions^ If the velocities in the depths of 

 the ocean are negligible, then the horizontal pressure gradients 

 are also negligible and the thermocline responds immediately to 

 a change in the free surface height provided the hydrostatic 

 pressure equation is valid. For such a case, the following 

 results anpear to be valid (within the framework of subsequent 

 approximations made in this report)? 



(i) For a varying wind with a period of three months or 



