This report covers work to January 1954 and was approved for publication 27 May 

 1954. The work was done under IO 15401, NE 120221-3 (NEL L4-1, formerly 2A5). 



statement of problem 



Investigate problems in oceanography through suitably devised methods, means, and 

 equipments. This report presents the results of physical oceanographic measurements 

 made in the shallow eastern Bering and Chukchi Seas. 



conclusions 



1. The oceanographic structure — temperature and salinity — of the region exhibits 

 pronounced layering with each layer nearly uniform vertically. The temperature-salinity 

 relations were consistent allowing a classification of the water masses, or layers, thus 

 making it possible to follow the geographical continuity of the water. 



2. The annual development of the water masses can be accounted for by (a) the 

 cooling effect of winter conditions and the freezing of the ice, (b) melting of the ice in 

 spring and summer, (c) drainage and run-off from the continental areas, (d) modification 

 by heating, and (e) modification by mechanical mixing. 



3. Water masses found in both the eastern Bering and Chukchi Seas are: (a) Deep 

 Shelf Water: uniform cold high-salinity water derived from winter conditions and lying 

 along the bottom in the deeper regions of the Bering and Chukchi Sea shelves, but not 

 present in the Bering Strait in late summer; (b) Modified Shelf Wafer. Deep Shelf Water 

 which has retained its high salinity, but since it is near the surface has been heated 

 several degrees; (c) Alaskan Coasfal Water, warm water along the coast with greatly 

 varying salinities caused by fresh water drainage from the west coast of Alaska; and 

 (d) Intermediate Water, a wedge of water lying between, and probably formed by 

 mixing between, Modified Shelf Water and Alaskan Coastal Water. 



Additional water masses observed in the Chukchi Sea are: (a) Siberian Coastal Water: 

 a counterpart to the Alaskan Coastal Water but lower in temperature, resulting from 

 drainage on the north coast of Siberia; (b) Ice Melt: low-salinity water at the surface in 

 the immediate vicinity of and in temperature equilibrium with the melting ice; and (c) 

 Modified Ice Melt: surface water fringing the Ice Melt and having similar salinities but 

 modified by heating. 



4. Summer currents in the eastern Bering Sea move slowly northward, increasing in 

 speed at Bering Strait due to the geographical constriction. Superimposed on this slow 

 drift is a faster northward coastal current confined primarily to the Alaskan Coastal 

 Water. The Siberian Coastal Current, the Alaskan Coastal Current, and the westward 

 drift along the southern margin of the ice pack combine to establish a broad counter- 

 clockwise circulation in the Chukchi Sea. 



recommendations 



1. Obtain observational data at other seasons of the year to establish conclusively 

 the annual cycle of oceanographic structure and currents. 



2. Undertake a limited study of the region between Cape Lisburne and Pt. Barrow to 

 tie together the Bering and Chukchi Sea investigations with those in the Arctic and 

 Beaufort Seas. 



