A STUDY OF ABLATION VARIATIONS ON THE TONGUE OF HINTEREISFERNER, AUSTRIAN ALPS

In the summer of 1989 a glacio-meteorological experiment was carried out on Hintereisferner, Austria. Here, we discuss the interpretation of detailed ablation measurements on the tongue. Two profiles arc considered: one along the glacier axis and one across the glacier tongue. At the crossing, an energy-balance station was operated, providing the necessary meteorological data. At all stakes the albedo was measured several times with a simple light-weight instrument (described separately in the Appendix). The absorption of solar radiation was calculated for all stake positions, taking into account local albedo, slope, aspect and shading effects. It appears that the differences in ablation can be explained almost entirely by the differences in surface albedo, both along and across the glacier tongue.