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A reconstruction method of historical glacier topographies and possible uses of these results are demonstrated in this article. This reconstruction was accomplished for 310 Alpine glaciers in South Tyrol, Italy. These glaciers are featured with a wealth of different historical (e.g. paintings, photographs and historical maps) and recent data sources (airborne laser scan based digital terrain model and digital orthophotos) that allow the reconstruction of the Little Ice Age maximum extension. These sources are among the best historical and recent documents of glaciers for the mid-nineteenth century. The results of this reconstruction visualize the ongoing climate change in a comprehensive way. The area changes between the time of the Little Ice Age maximum extent (around the year 1850) and the recent glaciation in 2006 amounts to a loss of 182.4 km2 or almost 66%. In the same time, the calculated mean equilibrium line altitude for all South Tyrolean glaciers rose approximately by 160 m.

A new approach to glacier inventory, based on airborne laser-scanner data, has been applied to South Tyrol, Italy: it yields highly accurate results with a minimum of human supervision. Earlier inventories, from 1983 and 1997, are used to compare changes in area, volume and equilibrium-line altitude. A reduction of 32% was observed in glacier area from 1983 to 2006. Volume change, derived from the 1997 and 2006 digital elevation models, was –1.037 km3, and an ELA rise of 54 m, to almost 3000 m a.s.l., was calculated for this period. Losses vary widely for individual glaciers, but have accelerated for all South Tyrolean glaciers since the first inventory in 1983.