Changes of glacier area in the Austrian alps between 1973 and 1992 derived from Landsat data

Abstract

Data from Landsat satellite sensors are used to obtain an inventory of 165 Austrian glaciers and their temporal change. Applications and modifications of existing remote sensing algorithms for glacier clas- sification are discussed. A trend analysis of the glacier area from a Landsat MSS scene (208/27, Sep. 13, 1973) and two TM scenes (193/27, Sep. 30, 1985 and Sep. 17,1992) reveals: - Glaciers with areas below l km2, usually excluded from direct observations, shrank significantly by 25 percent between 1973 and 1992. -- There is a strong decrease of glacier area between 1985 and 1992 for glaciers of all sizes. - Decrease depends on exposition, with highest values found for glaciers exposed to the south and east. - Accumulation and ablation zones of glaciers are distinguishable by remote sensing, so that the annual net mass balance may be estimated remotely