Retreat of Aurine and Pusteresi Alps glaciers in the last decades from a Landsat TM image on 2003 and previous results

This paper presents the results obtained from the analysis of one recent Landsat TM image for the study of the status of some glaciers on Eastern Italian Alps. Then these results are compared with a set of multitemporal Landsat images from the Eighties. A fuzzy set based classification technique permitted to quantify snow and exposed ice extents in glaciated areas. Integration with topographic information allowed to derive the elevation of glacier terminus, although the result is overestimated due to some problems with digital elevation data and frontal debris coverage. A comparison of front altitude changes data derived from satellite image processing with elevation measured during field surveys supports the knowledge of the size of glacier reduction of the last decades. On Aurine and Pusteresi Alps glaciers, the changes in the last twenty years result to be a reduction corresponding to the 40% of the glaciated surface in the '80s, but a lot of the glaciers are now characterized by a new extent debris coverage in the frontal zones.