The heat loss of 120 kg-cal/cm2 in a year was found by assumiBg that the temperature dif- 

 ference at the Nordkapp and Kola cross sections equals 1.5° and that the mean speed of the Nord- 

 kapp current in the sector has also a constant value of 5 cm/sec. It is possible that the horizontal 

 temperature gradient along the Nordkapp current is subjected to seasonal and secular variations. 

 We cannot, for the time beir^, assert it, but this variation is hardly significant. As to the sea- 

 sonal and secular variations in the speed of the eastvi^ard-moving Nordkapp water, they can, in any 

 case, be considered as established from the qualitative point of view. However, if the annual heat 

 loss to the atmosphere equals 120 kg-cal/cm2 at the assumed speed of 5 cm/sec and the temperature 

 gradient is 1.5°, then it is clear that, with variation in the speed of only 1 cm/sec, the heat loss 

 varies by 24 kg-cal/cm2, (i.e. , it exceeds considerably the result obtained by examining the tem- 

 perature variations in geographical coordinates). 



This reasoning gives an idea of the effect of Atlantic waters, and that of the Nordkapp current 

 in particular, on climatic conditions in the areas penetrated by air masses moving over the Barents 

 Sea and being heated by the water . 



The southern portion of the Barents Sea is a relatively simple case for the drawing of conclu- 

 sions on the influx and efflux of heat. The northern portion of the sea is, however, rather complex. 

 Here one is faced with the formation and melting of ice and with the condensation of water vapor 

 which is unavoidable in the summer time when the underlying surface is colder than the travelling 

 water masses. The presence of ice in the region, which absorbs considerable amount of heat dur- 

 ing melting and gives it off upon formation, simultaneously diluting or salinlfying the water, com- 

 plicates the calculation of incoming and outgoing heat. The complexity is increased by the influx 

 and efflux of ice whose quantity varies from year to year, in each of the marginal seas of the Arctic 

 Basin. 



It is, for instance, assumed that from the central section of the arctic about 2,500 km"^ of sea 

 ice is annually carried out via the Greenland-Spitsbergen Strait. Neglecting the temperature of the 

 ice, we find that about 20. 10-*-^ kg-cal of heat is given off to the atmosphere by the sea during the 

 formation of the ice. This heat has of course played its part in the raising of air temperature over 

 the Arctic Basin. 



Still more complex is the problem of the influx and efflux of heat in such seas as the Kara, 

 Laptev and other seas where, in addition to the ice, the discharge of heat by rivers is significant. 



LITERATURE: 34, 49, 62, 77, 124. 



Section 26. The Concept of the Water Balance 



The circulation of moisture on the earth, according to Bruckner, who assumes that the quan- 

 tity of water does not change in the ocean, is expressed by the following equations: 



Precipitation on the ocean = evaporation from the ocean — continental runoff. 



Precipitation on land = evaporation from the land + continental runoff. It is evident that these 

 formulae are valid only for a great number of years when the annual random deviations from mean 

 value can be eliminated. 



It is assumed that only a small part— namely, about 10 per cent of the moisture evaporating 

 from the ocean is carried away and precipitated on land, returning later to the ocean in the form of 

 continental runoff. The remaining portion of the water that has evaporated from the ocean is pre- 

 cipitated back into the same ocean. However, its distribution over the ocean areas is far from uni- 

 form. In lower latitudes, except for the pre -equatorial belt of the Northern Hemisphere, the evapT 

 oration exceeds precipitation, and here the ocean is constantly salintfied. In temperate and high 



60 



