Suretta Sud Glacier - Servizio Glaciologico Lombardo

The 2008 Glaciological survey 1
“How did the glaciers fare during the last sum- a slight decrease. Despite the very negative
mer?” This is the most frequent question that scenario, this is a slight improvement over the
mountain lovers, friends and curious people previous year, when all glaciers had strong to
have been asking us since last September. moderate decrements. Curiously, the sectors
Such direct and concise question is worth a whose snow cover was better than their his-
similarly short and clear answer: “Badly”. Then torical average value in the early summer days
the astonished speaker: “But why? A bad sum- were the ones to suffer the worst decrements.
mer again? With all the snow that fell down ... What are the explanations
and the bad weather we have had …” At this for such a negative season?
point, it is worth to analyse in depth a season The answer has implicitly been outlined in
that, despite the very negative result, has the snow-meteorological report already.
shown some shy signals of a recovery if com- Despite an amount of precipitation in line
pared to the glaciological disasters of the past with the average value for the season,
few years. The differences among the various thanks mainly to the April-May period, the
mountain sectors of Lombardy, almost zeroed snow did not last until the end of the sea-
during the last years because of very negative son; such result is a consequence of the
dynamic indexes everywhere, this year have high temperature of the summer months.
become visible again. So, it is clear that the The thickness reduction of the glacier’s fronts
western sectors have fared better than the was comparable to that of previous years; the
eastern ones: the Spluga/Lej, Codera/Masino, frequent May precipitations probably led to a net
Disgrazia, Orobic Alps, though undergoing a differentiation between the upper basins, well
negative season, have ended with some re- fed by snowfalls, and their rain-washed termini.
sidual snow coverage over all apparatuses. By the end of July, the residual snow had
Photographic observations and field surveys disappeared almost everywhere under 3200
proved that some small glaciers had an almost m a.s.l., letting the hot August and early
positive season: the best examples are: Mor- September days to melt down the exposed
tee, Calvo, Rasica Est, Cassandra Centrale, ice and, where present, most of the residual
Dente di Coca and Pizzo dell’Omo Ovest. Un- snow. Locally, the snow cover lasted till the
fortunately all are very small apparatuses; their end of the season above 3300 m a.s.l. and on
combined size being only 2% that of the Ad- some glaciers with avalanche accumulation.
amello Glacier which, on the other side, had a The SGL Glaciological Survey, though delayed
heavily negative season. For the same reason, by the abundant snowfall of mid-September,
all glaciers belonging to the SGL sample list has nevertheless produced meaningful data,
showed a negative trend versus the 2007 situ- having investigated 95,4% of the glacialized
ation. The 47 glaciers of the sample were cho- surface of the Region. The most important
sen for their size and for being representative results are the largely negative mass bal-
of their own sectors. 23,4% of them showed a ances and the investigation of morphologies
dynamic index pointing to a strong decrease, peculiar to a phase of glacial dissolution: the
59,4% to a moderate decrease and 19,2% to deep bédières (Campo Nord), the ever wider
1 For the survey methodology see www.sgl.cluster.it
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2008 glaciological
Survey