Tracing glacial disintegration from the LIA to the present using a LIDAR-based hi-res glacier inventory

Glacier inventories provide the basis for further studies on mass balance and volume change, relevant for local hydrological issues as well as for global calculation of sea level rise. In this study, a new Austrian glacier inventory updating data from 1969 (GI I) and 1998 (GI II) has been compiled, based on high resolution LiDAR DEMs and orthophotos dating from 2004 to 2011 (GI III). To expand the time series of digital glacier inventories in the past, the glacier inventory of the Little Ice Age maximum state (LIA) has been digitalized based on the LiDAR DEM. The resulting glacier area for GI III of 415.11 ± 11.18 km2 is 44% of the LIA area. The area losses show high regional variability, ranging from 11% annual relative loss to less than 1% for the latest period. The glacier sizes reduced from LIA to the latest period, so that in GI III 47% of the glaciers' areas are smaller than 0.1 km2.