Some Aspects of Energy Balance and Ablation of Storglaciären, Northern Sweden

Abstract

A comprehensive glacio-meteorological experiment was conducted on Storglaciaren in both the second half of the 1970s and in the 1990s. For a 40 day period in July and August 1994, the surface energy balance was calculated from measurements obtained by a meteorological station on the glacier. Melt rates obtained as residuals in the heat balance equation were compared to measurements with ablatographs and ablation stakes in the vicinity of the climate station. On average, the contributions of the net radiation and the turbulent fluxes were roughly two thirds and one third, respectively. Calculated melt energy was considerably underestimated on days characterized by dense fog or precipitation. The energy balance was extremely sensitive to the choice of surface roughness. The roughness length for the logarithmic profile of wind speed was higher than the roughness length for temperature by two orders of magnitude.