I ghiacciai delle Alpi Breonie, Aurine e Pusteresi nell’immagine Landsat TM del 7.9.85

The Breonie, Aurine and Pusteresi Alpine Glaciers through the 7 September 1985 Landsat TM Image

Abstract

Since the data relative to Italian glaciers are being updated, it was proposed to use the Landsat TM images simultaneously with conventional observational methods. For this purpose an interpretation procedure was developed through an algorithm of classification to compute the extent of glacier and snow cover surfaces. The procedure was applied to glaciers included in the third quadrant of the Landsat TM 192/27 image of 7 September 1985, represented by the glaciers of the Breonie, Aurine and Pusteresi Alps and the data obtained are compared with those of previous alpine glacier inventories. The comparison with the 1959-1962 data showed a positive evolution, more evident for the Pusteresi glaciers and less towards the glaciers of Breonie. The comparison with the 1982 data showed a tendency to regress. The more pronounced differences with respect to the previous inventories regard a few very small glaciers. The comparison of results is difficult for these glaciers due to the different inaccuracies in the various measuring methods used to obtain glacier data. It is suggested to use the same methods to reduce the systematic errors implicit in all surveying techniques.