Long-term glacier observation series represent the basis for reconstructing secular trends and for investigating the physical processes driving the response of glaciers to ongoing climatic changes. Since its origin, the Italian Glaciological Committee (CGI) recognized the relevance of systematic monitoring of Italian glaciers and, in particular, started from the measurement of frontal variations. Annual surveys are regularly conducted since the end of the 19th Century and were never interrupted since 1911, with the only exception of war periods. Glaciological surveys from the CGI supply therefore one of the longest series of observations of the glacial front variations in the world. Furthermore, large amount of data and a precious photographic documentation were collected during the annual glaciological surveys. The photographic archive of the CGI holds tens of thousands of images related to Italian glaciers imprinted on various media (negatives, black and white, and colour print, slides, DVDs and precious as delicate glass plates).
The results obtained in the framework of the glaciological campaigns (http://www.glaciologia.it/i-ghiacciai-italiani/le-campagne-glaciologiche/) are regularly published since 1927 in a dedicated section of the CGI Bulletin, today known as Geografia Fisica e Dinamica Quaternaria http://gfdq.glaciologia.it/issues/). At present, approximately 150 glaciers are monitored every year by a large number of surveyors, also linked to other volunteers associations.
In the framework on the Nextdata Project, we collected all the data related to frontal variation surveyed by the CGI during the last 100 years. all the data have been validated and storaged in a spread sheet to perform analysis of glaciological data of the Italian Alps.
The Italian glaciers, since the end of the maximum Holocene advance have experienced a phase of generalized retreat, accentuated in the 50s of the 20th Century, which was followed by a slight advancing stage culminated in the late '70s and early '80s. Since the '90s there was a general withdrawal of almost all the Italian glaciers. The mean annual snow line rose about 100 m, as a mean.
About a dozen of glaciers are presently monitored for measuring the glaciological mass balance. All the collected data related to the monitoring of frontal variations and annual mass balances measured in the Italian Alps contribute to the World Glacier Monitoring Service (WGSM) database (www.geo.uzh.ch/microsite/wgms/).
Annual mass balance of selected Italian glaciers is measured since 1967 (e.g. Careser Glacier). The cumulative net mass balance of the Careser Glacier calculated by direct glaciological surveys registers about – 50 m w.e. from 1967 to 2012 (Carturan et al., 2013).
The longest mass balance series show an increase of mass loss rates, mainly induced by longer and warmer ablation seasons. In the decade from 2004 to 2013 the mean annual mass balance varied from - 1788 to -763 mm w.e. yr-1 (Carturan et al, 2016). The combination of October– May precipitations and June–September temperatures are responsableresponsible of negative glaciers mass balance but an important role is played by rapid geometric adjustments in driving the accelerated responceresponse of glacial bodies
