Suretta Sud Glacier - Servizio Glaciologico Lombardo
Suretta Sud Glacier - Servizio Glaciologico Lombardo
Suretta Sud Glacier - Servizio Glaciologico Lombardo
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2008 glaciological<br />
Survey<br />
The terminus variations The sample glaciers of Italian Glaciological<br />
Committee (CGI)<br />
Some glaciers subject to a complete survey have their linear terminus variations measured.<br />
The algebraic symbol indicates a downvalley advance (+) or an upvalley withdrawal (-). The<br />
variation is not directly linked to the snow-meteorological trend of the season. Many are the<br />
additional factors (such as: glacier response time, bedrock morphology, flux velocity, etc…)<br />
that make this parameter of little use in evaluating the state of the glacier in the survey year.<br />
However these glaciers carry an historical series of linear front measurements, which makes<br />
their continuous monitoring extremely interesting. Our glaciers, along with other Italian glaciers,<br />
are part of the historical sample of ice bodies surveyed by CGI. The sample is divided<br />
into two sets. Groups 1 and 2, selected on the basis of their glaciological importance and<br />
representativeness, include the glaciers measured once a year; group 3 include the glaciers<br />
measured on a rotational basis, generally once every 5 years. In the present phase of significant<br />
and prolonged decrements, the front measurements are coherent with the dynamic<br />
index: out of the 26 glaciers with annual measurement, only 1 has held its previous position;<br />
all the others have shown sometimes consistent shrinkages. The Passo di Chiareggio<br />
and Verva Maggiore <strong>Glacier</strong>s multi-year decrements were paroxysmal and caused by the<br />
dismemberments of dead-ice blocks, a typical feature of an intense withdrawal phase.<br />
Tab. 8: Summary of terminus measurement data, versus 2007 and previous years.<br />
Variations versus 2007 decrements increments unchanged<br />
26 25 (96,2 %) 0 1 (3,8 %)<br />
Variations versus previous years decrements increments unchanged<br />
3 3 (100 %) 0 0<br />
Fig. 7: The terminus variations of the Lombardy’s sample glaciers over the last 18 years.<br />
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