An additional characteristic of the arctic is precipitation in the form of snow and hail in sum- 

 mer, which can be expected any month of the year in aU the seas of the Soviet Arctic. On the 

 other hand, along the ice edges of the Greenland and Barents Seas, rain is possible even in the 

 winter time. Thus, on 8 January 1940, the Sedov expedition reported rain at 80°45' north latitude 

 and at latitude 2°28' east longitude. 



Icy rain is only rarely observed In the arctic. Such rain was observed during the Sad ho ex- 

 pedition at the end of August 1935 along the east coast of Franz Joseph Land. 



As a rule, precipitation lowers the surface temperature of the World Ocean. Indeed, the 

 temperature of precipitation is usually somewhat lower than the temperature of the air, and the 

 latter is usually lower than the temperature of the sea. Cold currents and coastal areas of seas in 

 summer and at offshore winds are exceptions to this rule. 



Also, in this respect, the effect of the Insignificant amount of precipitation in the liquid phase 

 is limited in the arctic. The effect is more significant in regard to the precipitation occurring in 

 the solid phase on the ice-free sea surface, or in the liquid phase on ice. 



The liquid precipitation on snow or ice in spring and summer is characterized by its warm- 

 ing, radiational and mechanical effect. 



The thermal effect lies in a certain increase of temperature or even in the melting of a cer- 

 tain amount of snow. It is not difficult to show that the thermal effect of even a heavy rainfall is 

 insignificant. 



The radiational effect lies in the lowering of the albedo of snow as a result of moistening. 

 Thus, after a rainfall, the ability of snow to absorb radiation is considerably increased. 



The mechanical effect lies in the fact that the rain drops, penetrating into the snow make it 

 porous. In the consequence, the area of the snow surface that receives radiation is increased. In 

 addition, part of the snow is washed out to sea. 



The role of solid precipitation is determined by the following facts : 



1. The solid precipitation on ice-free areas of water before the winter has set in lowers the 

 surface temperature of the ocean, but if the temperature is near the freezing point, the solid pre- . 

 cipitation accelerates ice formation. 



In the latter case, a special type of ice — snow slush — can be formed if the snowfall is heavy. 



2. Solid precipitation falling on ice in summer increases the albedo of the ice, thus retard- 

 ing its melting. 



LITERATURE: 34, 62, 77. 



Section 24. Coastal Precipitation 



The coastal precipitation on the seas of the Soviet Arctic has several characteristics: 



1. More than half of the entire river influx is received by the Kara Sea, and the influx de- 

 creases toward the east. 



52 



