Vol. 7, No. 2, 120-132, 2008

Abstract
The disappearance of some glaciers of the world is due to the global climatic heating and other correlated phenomena. This also endangers the other glaciers, providing many repercussions on the availability of natural water resources for agricultural, civil and industrial purposes. This research developed a study process to analyse the status of some Alpine glacier groups (Adamello, Ortles-Cevedale and Bernina) localised in the North of Italy, the “water tower” of Europe. The investigation was based on a set of three multi-temporal Landsat scenes acquired with the sensors MSS, TM and ETM+ combined with other types of information (2D, 3D and thematic data). The GIS based analysis, supported by remote sensing processing, allowed the extrapolation of the meaningful parameters for the glacier dynamism in the temporal displacement of observation. The total areas of the glacier, the extension of the accumulation and ablation zones, integrating the information derived by DTM, were very important to calculate the Equilibrium Line Altitude (ELA) and the Accumulation Area Ratio parameter (AAR). Furthermore the data acquisition, the classification analysis and the management of the database in the GIS with the final presentation of the results in a good visual layout, were performed by the open source software ILWIS 3.4. Also for this reason, evaluating the results, the advantages of this methodology can be underlined: simplicity, low cost and reliability.

ISSN 1729-3782