OCEANOGRAPHY 



67 



the windward cross-reef inflow of surface water. At a max- 

 imum (high tide, active surf), this inflow is approximately 

 equal to the downwind transport of the lagoon surface 

 layer; during these intervals, upwelling is not required by 

 continuity to supply the wind-driven surface transport. The 

 essentially vertical homogenous water in Enewetak Lagoon 

 suggests that surface water mixes with bottom water 

 before reaching the leeward side. It also does not allow 



any conclusions regarding the presence or absence of 

 upwellings from distributions of water properties. At Bikini, 

 Ford (1949) was able to follow the motion of discrete 

 water distinguished by salinity variations. 



Surface, mid-depth, and deep water salinities at 

 Enewetak are shown in Figs. 13a, b, c. These salinity con- 

 tours show some of the general features of lagoon 

 circulation. Surface water was slightly less saline than deep 



(b) 



(c) 



Fig. 13a, b, c Salinity for surface (0 to 10 m). mid-depth (10 to 30 m). and deep (30 to 50 m) water. (Collected by S. V. 

 Smith, July 26 to Aug. 16, 1974.) 



