Ablation and Heat Balance of the Yukikabe Snow Patch in the Daisetsu Mountains, Hokkaido, Japan

Abstract

A good correlation was found between the ablation of snow and degree day index (cumulative values of positive daily mean air temperature) during the summer of 1978 on the Yukikabe snow patch in the Daisetsu mountains, central Hokkaido. The volume change of the snow patch in the ablation season of any year can hence be estimated from air temperature using this relationship. Each of the heat-balance terms controlling the ablation is evaluated separately by using empirical equations and assumed values for meteorological parameters at the snow patch. Triangular diagrams are constructed in order to illustrate the relative contributions of sensible heat, latent heat, and net radiation, the main three heat sources. A higher contribution from sensible and latent heat is found for the snow patches of Japan than for many glaciers and ice caps elsewhere. This may be due to higher mid-summer air temperatures than in other glaciated parts of the world.