A vent'anni dal Lago Effimero (Ghiacciaio del Belvedere, Monte Rosa): eredità di un evento emblematico per le Alpi

The article recalls a particular moment in the evolution of the Belvedere Glacier (Monte Rosa Group, Italian Western Alps) at the beginning of the 2000s. A rapid and intense surge caused astonishing transformations of the glacier and the concurrent formation of a large epiglacial lake (named "Lago Effimero"), which started a complex civil protection operation to reduce the risk of an outburst flood. The glacial lake outburst flood occurred in the summer of 2003 fortunately without significant consequences and the surge ended shortly afterwards. In any case, the Belvedere glacial basin still remains a very active geodynamic laboratory. These pages recall the main natural instability processes that have occurred since 2005 (rock and ice avalanches, collapse of moraines, debris flows) in a context continuous warming of the air temperature which is undermining the integrity and stability of the cryosphere. The effects of climate change are reverberating also on the famous Monte Rosa east face which is losing its magnificent ice cover.