There is a fascinating piece of reportage (with spectacular animation) on the BBC web site, relating to the recent disaster in the Swiss Alps.
https://www.bbc.co.uk/news/resources/idt-c7f929de-96a9-45e5-b1bb-31de82fce72d
Thank goodness there was no loss of life, since the idyllic village had already been evacuated, prior to the catastrophic event. I thought, before I looked into this, that the "glacier collapse" took place in the upper part of a regenerated glacier, like that of Supphellebreen at Fjaerland in Norway -- but no, this was a very small and very dynamic independent glacier (Birch Glacier) in a high mountain environment. High rates of snow accumulation, steep slopes, and rapid ice flow under the influence of gravity, on slopes dominated by frost shattering and rockfalls. Permafrost melting and rainfall in the Alps (as distinct from snowfall) were contributary factors in causing additional debris mobility.
The old photos show a substantial fan of debris close to the village, with no clear terminal or other moraines.
There is no doubt at all that collapses like this will now occur with increasing regularity in all of the high mountain environments where there are thousands of vulnerable glaciers of this type.......
(For very good enlargements of the images, just click on them.)
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