It is known that the ice fields' ability to absorb heat increases with the passage of time as the 

 ice fields become darker and are covered with snow puddles. The law of this increase is completely 

 unknown to us . The absorption of heat from the air depends on the speed of wind , temperature and 

 humidity of the air and also on other factors. 



Let us make a rough assumption that the quantity of heat coming from above (as a result of 

 radiation and heat exchange with the air) remains unchanged during the period of time under con- 

 sideration and that the absorption ability of the ice increases proportionately with time, i. e. , 

 f = bT. Then we obtain from equation (1) 



bTdT =8.Mh. 



Integrating, we find that 







-^ T'- = S..X/Z, 



'y-'2 



2 8,.X/? 



(2) 



In order to determine the coefficient, b, let us suppose, e. g. , that in the given region the 

 reduction of ice thickness due to melting continues from 21 May to 1 September; i. e. , 100 days, and 

 that the thickness of the ice fields decreases by 100 cm during this period. 



Substituting in equation (2), T = lOO and h = 100, we obtain 



2 S,-X/t _ 2 SX 



r- ~ 100 • 



6 = 



(3) 



Substituting equation (3) in equation (2), we obtain 



T2= 100 /z, 



where T = time, expressed in days, 



h = melting, expressed in centimeters. 



I have compiled table 88 according to this equation. 



TABLE 88. APPROXIMATE REDUCTION OF ICE THICKNESS (DUE TO 

 MELTING FROM ABOVE) IN CM, STARTING WITH 21 MAY 



315 



