The Glaciological Studies of the Baffin Island Expedition, 1950: Part IV: The Heat Exchange at the Surface of the Barnes Ice Cap During the Ablation Period

Abstract

AbstractThe heat exchange takes place in two stages: (i) the atmospheric heat causes melting of the whole of the annual snow accumulation and leads to the formation of slush rivers; (ii) some of the melt water refreezes to form a new layer of ice superimposed on the original ice, which is warmed by the latent heat yielded to it. A theoretical estimate of the rate of formation of the superimposed ice, and of the temperature change in the original ice, is given, which agrees reasonably with the actual measurements. A rough measurement of the melt water run-off checks with the observations of ablation and superimposed ice. The total energy available for melting is estimated approximately from the meteorological observations; it underestimates the actual ablation. About 70 per cent of the total ablation energy (47 cm. water, total ablation) is disposed of as melt water that is discharged from the ice cap surface; the remainder goes as sensible heat to the low temperature ice.