The cumulative, or total, radiation consists of incident and diffuse radiations. 



As was established, during twilight and under conditions of dense clouds only diffuse radiation 

 is available; at other times the cumulative radiation takes place. 



In certain regions and in certain seasons the diffuse radiation is considerably more intense 

 than the incident radiation; in others the situation is reversed. Thus, at Slutsk in the "grayest" 

 month, December, the incident radiation makes up only 22 per cent of the total radiation; in the 

 sunniest month, July, the incident radiation makes up 68 per cent. 



TABLE 11. MONTHLY SUMS OF CUMULATIVE RADIATION (G-CAL/CM2) 



In table 11, according to Kalitin, are presented the monthly sums of cumulative radiation for 

 Bukhta Tikhaya, Slutsk and Feodossiya. It is seen from the table that in June, for instance, the 

 cumulative solar radiation in Bukhta Tikhaya is 31 per cent greater than at Slutsk and 8 per cent 

 greater than at Feodossiya. * 



TABLE 12. HEAT SUMS OF THE CUMULATIVE RADIATION IN THE SEAS 

 OF THE SOVIET ARCTIC (G-CAL/Cm2) 



In table 12 are presented averaged data by Chernigovskiy who calculated the mean Influx of 

 the cumulative solar energy for the seas of the Soviet Arctic, per year and summer months (May, 

 Jime, July). In the last column is shown the ice thickness in cm which could be melted by this 

 amount of heat if all of it were used for the melting of ice . 



This is a very representative table because it discloses the fact that in the arctic the ice 

 regime is determined mainly by the portion of radiation which is actually absorbed by the surface 

 of ice and water and not so much by the amount of solar radiation that reaches the surface. 



LITERATURE: 62, 77, 81, 82, 138. 



*This is confirmed by the fact that in 1932 the maximum (diurnal) value of the cumulative 

 solar radiation on the South Crimean Coast was 450 g-cal/cm^. During the cruise in the Sadko 

 at the end of August 1935 along the north coast of Spitsbergen, the cumulative solar radiation also 

 reached 450 g-cal/cm"^ per day according to VI. A. Verezkin. 



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