The reversibility of the Siberian high and Aleutian low explains the monsoonal character of 

 winds in the Japan and Okhotsk Seas and likewise the monsoonal character of winds of the Soviet 

 Arctic. This feature is most clearly evidenced in the Laptev and East Siberian Seas. In the 

 Chuckchee Sea it is slightly obscured by other and stronger factors. 



According to Vize, a change of winds from the Atlantic - continental group (south, southwest, 

 west) to winds of the Polar group (north, northeast, east) occurs along the whole Soviet coast in 

 April, and a reverse change in September. Figure 161 shows the variability of intensity of winds 

 of Polar and Atlantic-continental groups according to Vize. 



XI XII 



Figure 161. Variability of intensity of Atlantic, continental and polar winds. 



4. The Arctic high - located over the Central Arctic Basin, and the Greenland and Canadian 

 highs which are part of its system. Little is known of the formation of this system. 



It would be natural to assume that the Greenland and Canadian highs , located over large land 

 expanses, should be especially clearly defined in the winter like the East Siberian high. In the 

 summer the Canadian high, like the East Siberian, should be replaced by an area of decreased 

 pressure. The arctic high itself, on the contrary, shoiild be lessened in the winter, since despite 

 the fact that the Arctic Basin is almost completely covered with ice, it nevertheless transmits to 

 the atmosphere a considerable amount of heat in the winter during formation of additional ice lay- 

 ers. In the summer on the other hand, the arctic high should to all appearances join up with the 

 Greenland high and occupy a greater expanse. 



Figures 162 to 165 show the seasonal distributions and in figure 166 the annual distribution of 

 atmospheric pressure over the Arctic Basin. These charts were compiled by Dzerdzeyevski as the 

 average for 1937 to 1939. Three years is too short a period to permit us to ascribe climatologic 

 significance to these maps. Their advantage lies in the fact that, in contrast to other maps, they 

 are based on actual observations in the central arctic, made by the station "North Pole" and the 

 icebreaker Sedou . 



426 



