from the south forms a wedge beneath the cold surface water and pack ice. 

 This phenomenon takes place in the deeper waters of the survey area. As 

 a result, positive vertical gradients are found in these areas when 

 approaching the ice boundary and beneath the pack ice for some distance 

 to the northo 



2. Salinity 



Surface salinity values (Fig, U) ranged from 31.09 °/oo in open water 

 near the Alaskan Penisula to 33 .OS °/oo in the southwestern part of the 

 survey area. Higher salinity values were found in the open waters, par- 

 ticularly south of the ice boundary. Salinity values tended to be lower 

 in the shallow waters overlying the shelf where dilution from river runoff 

 occurred. Figures 5 through 10 show the vertical distribution of salinity 

 to be variable in shallow water and to incirease with depth where deep 

 water is present, 



3, Density 



The pattern of density distribution shown in Figures 5 through 10 is 

 similar to that of salinity. Variable conditions are typical of the shoal 

 areas. An increase in density with depth is found where the greater depths 

 occur, 



Uo Sound Velocity 



Surface sound velocities ranged from U,700 ft./sec, at station 3 with- 

 in the pack ice to U,770 ft, /sec, at station 35 in open water south of the 

 ice boundary (Figs, 5 through 10), Due to the shallow nature of the area, 

 no definite sound channel could be defined. In each section sound velocity 

 increased with depth, the rate of increase being greatest in the deep water 

 areas,- The maximum sound velocity observed was U*808 ft,/sec, at a depth 

 of 300 meters (station 38), 



C, Physical Prq)erties - Spring 1955 



Surface temperatures and salinities observed in the Bering Sea between 

 20 April and 2? May are shown in Figures 11 and 12, Sections depicting the 

 vertical distribution of physical properties during this period are presented 

 in Figures 13 through 16, 



1, Temperature 



Surface temperatures during the spring of 1955 are shown in Figure 11, 

 The 0°C isotherm which approximated the position of the ice edge during 

 the winter had moved about one degree northward. Isothermal surface water 

 (having temperatures less than -1,0°C) is primarily confined to the area 

 north of St, Matthew Island, 



Surface temperatures ranged from -1,80°C near Bering Strait to U«OU°C 



