62 



M. C. Miller et al. 



imagery over the thaw period have been used to determine the thaw dates 

 and in this way to distinguish between shallow and deep lakes in northern 

 Alaska (Sellmann et al. 1975). 



HYDROLOGY 



Snowfall and Rain 



The total recorded snowfall at the NCAA station at Barrow may be 

 quite misleading as this is a cumulative number calculated from 

 measurements made after every snowfall. Later, compaction plus snow 

 loss by sublimation and drifting takes place. Thus, the total snowfall from 

 the fall of 1959 until the spring of 1973 ranged from 45.2 to 103.9 cm snow 

 yr ' (Table 2-2) but the maximum snow pack ranged from only 17.8 to 

 30.5 cm. In fact, the official reading of snow on the ground on 1 June, just 

 before the thaw began, was 5.1, 7.6, trace, and 12.7 cm for 1970, 1971, 

 1972, and 1973, respectively. A better measure is of the snow actually on 

 the pond site at the beginning of melt as well as an estimate of its water 

 content (Table 3-6). The snow depth on the pond site was 2 to 6 times 

 greater than the depth at the Barrow station (1971 to 1973) and the water 

 content was also higher than might have been expected. These facts 



TABLE 3-6 Snow Depth and Water Content of Snow, IBP Pond Sites 



