The impact of recent glacier fluctuation and human activities on the permafrost distribution: a case study from Stelvio Pass (Italian Central-Eastern Alps)

The relationships between permafrost and glacier fluctuations were analyzed near Stelvio pass (Italy). The glacial evolution was reconstructed by comparing historical documentation, vegetation surveys and geomorphology. Patchy permafrost occurrences, detected by geophysical techniques (VES, resistivity tomography, seismic, EM-31) correspond well with ecological indications derived from vegetation surveys. Meteorological data, with reconstructed MAAT lower than -2°C since 1927 indicate a suitable anvironment for permafrost aggradation. Differences in permafrost thickness (10-20 m) and active layer thickness (3-5 m) were determined through geophysical surveys. These differences can be explained by vaying snow distribution, topographic characteristics of the terrain and by different times since deglaciation. In addition, disturbance of the terrain in 1987 may have influenced the ground thermal regime