The presence of what appears to be a localized estuarine circulation 

 north of the Lena River Delta may be caused by the existence there 

 of a shallow submarine feature. 



Conditions of dissolved oxygen supersaturation were observed 

 in the Laptev Sea during August and September 1963. At that time, 

 lower dissolved oxygen values were observed in Lena River effluent 

 than in water in the northern and western Laptev Sea, which was frequently 

 supersaturated. Dissolved oxygen supersaturation usually was observed 

 in the upper 30 meters, but on one station it was observed as deep 

 as 53 meters. 



High observed dissolved oxygen values most likely can be attributed 

 to photosynthesis. 



C. The East Siberian Sea. 



The temperature and salinity distributions observed in the East 

 Siberian Sea by NORTHWIND and BURTON ISLAND were highly stratified, 

 similar to those observed in the Laptev Sea. Temperatures were noted 

 to increase vertically from the bottom and toward the Siberian coast, 

 and salinities were noted to decrease vertically from the bottom 

 and toward the coast. 



Water of three temperature-salinity relationships was observed 

 in both 1963 and 1964. Near the coast between the Indigirka River 

 and Chaunskaya Bay, temperatures above 0°C were noted with salinities 

 below 20 %(, • In the sea's shallower western regions, temperatures 

 from -0.5 to -l.A'C were observed with salinities from 10 to 28(7gp . 

 Both of these temperature-salinity relationships most likely can 

 be attributed to river runoff, with cooling and mixing in transit 

 accounting for the colder temperatures and slightly higher salinities. 

 Since this water was observed near the coast, it has been termed 

 "Siberian Coastal Water". Water in the eastern East Siberian Sea 

 through Long Strait and into the Chukchi Sea was observed to have 

 temperatures from 1.4* to -l.S'C associated with salinities from 

 28.0 to 33.1 %o . Because these temperature and salinity characteristics 

 are similar to those in the Eurasian Arctic Basin, this water has 

 been termed "Arctic Basin Surface Water" although some of it probably 

 originates in the Bering Sea. 



In the East Siberian Sea in 1964, three anchor stations were 

 occupied, and Nansen casts and current observations were made. Temperature 

 and salinity measurements showed changes in surface temperature as 

 great as 1.30°C and changes in salinity as great as 6.25 %o over 

 a 25-hour period. Similar, though generally smaller, variations 

 were noted at all depths sampled. 



Sustained winds of 18 m/sec for a 12-hour period were effective 

 in achieving near isohaline conditions down to 8 meters on anchor 

 station 4. 



43 



