Suretta Sud Glacier - Servizio Glaciologico Lombardo

Fig. 7: Suretta Sud Glacier: the annual net mass balance for the period 2001-2008.
installed at the end of the 2003 glaciological central sector, where the transfer of ice
year, which given the following results:
from the upper portions is active;
• stake number 2 is protruding 50 cm less; • The situation is virtually stable in the
• stake number 1 is protruding 33 cm upper part of the glacier along the right
more.
edge, probably due to avalanche accu-
It is evident that the traditional evaluation of mulations.
the mass balance through a few points may be A summary of the net mass balance results
ambiguous and prone to errors. In our case, for for the period 2001-2008, calculated with the
example, a greater number of stakes would be above described method, is reported in Fig. 7.
needed in order to obtain meaningful results. It is easy to see that the 2002-2003 season,
The installation and maintenance of a network with a loss of 2800 mm w.e., was the worst of
of ablation stakes, without any doubt, would be the period, followed by the 2006-2007 (-2670
more onerous than the glacial survey through mm w.e.) and 2005-2006 (-2500 mm w.e.)
topographic methods.
ones.
An examination of the Fig. 6 chart, represent- Both these periods were in fact charactering
the distributions of thickness variations, ized by anomalous thermal trends: the 2006
highlights that:
ablation season, besides lasting until October,
• The greatest losses were recorded at the was the warmest since 1971 while the month
lower left side, where the altitude differen- of April 2007 was recorded as the hottest of
tial sometimes exceeded 4 m;
the last 150 years, thus starting an anticipated
• The minimum losses happened in the ablation season. The 2007-2008 net balance
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mass balance