It has already been shown that the water exchange of the Arctic Basin and the Greenland Sea is 

 determined by many factors: positive fresh water balance, difference of densities, etc. But the 

 determining factor is undoubtedly the transfer of ice from the Arctic Basin into the Greenland Sea 

 and the water deficit in the Arctic Basin which is due to this ice transfer. 



In other words, the basic factor responsible for the general circulation of arctic ice is the 

 nature and intensity of atmospheric circulation over the Arctic Basin and over the basins of the 

 World Ocean adjacent to it. 



LITERATURE: 67, 70, 72, 77, 122. 



Section 153. Ice Circulation in the White Sea* 



In respect to its geographic position, shape, bottom topography and other features, the White 

 Sea occupies quite a peculiar place among the northern seas of the Soviet Union. 



The distinguishing feature of the White Sea is the separation of its deep part (basin), with 

 depths up to 340 m, from the Barents Sea by a long, narrow and shallow strait (neck). This fact 

 makes the White Sea a sea, in the full sense of the word, in contrast to the other seas of the Soviet 

 Arctic. 



In the neck of the White Sea, in the region of Three Islands a very narrow (about 1 to 2 miles) 

 trough over 40 m deep connects the deeper parts of the White and Barents Seas. The distance 

 between 20 m isobaths here is also extremely small (about 8 miles). In addition, in the same 

 region, approximately to the east of the 42nd meridian, there are a number of low, rocky islands. 

 Ice accumulations form on these islands in the winter, and floating, detached hummocks (nesiak) 

 adhere to them. In this manner, to the east of Terski-Orlovski Cape an obstacle is created to ice 

 movement, both wind-caused movement and movement resulting from currents. This is particu- 

 larly noticeable in the spring. Here the ice remains longest and hinders navigation at a time when ice 

 has already disappeared in the basin and neck of the White Sea. 



Figure 172 shows the condition of ice in the neck of the White Sea, illustrating the above 

 (data from air reconnaissance made on 14 April 1943). All the remainder of the White Sea was 

 practically free of ice. 



The next distinguishing feature of the White Sea is the strong tides, thanks to which even 

 Onega Bay, which is separated from the basin by the ridge of the Solovetskya Ostrova, and which is 

 shallow and has a great number of coastal islands, does not freeze up completely even in severe 

 winters. 



*The White Sea, small in size and capable of being covered by air reconnaissance in several 

 hours, is an amazingly convenient field for all sorts of observations of the dynamics and heat budget 

 of the ice cover. Systematic observations of this sort were begun in 1941 and 1942, and there is no 

 doubt that the results of these observations may be applied to the ice of the arctic seas. This fact 

 is partly responsible for the insertion of a special paragraph into the present book. 



437 



