Future changes in the ice reservoir

Abstract

In summer, meltwater from glaciers supplies a reliable contribution to runoff in the alpine headwater regions. In a warming climate with reduction of the glacier surface and depletion of the ice reservoir, this contribution is increasing in an initial stage, but decreasing on the long run. The observations of glacier retreat over the past century and an increase in global temperatures are indications of the impressive dynamics of the processes that have continued to accelerate as a result of interactions and feedback, especially in the last two decades. These processes are calculated in precise detail in DANUBIA using the SURGES (Subscale Regional Glacier Extension Simulator) glacier sub-model, so that even the future extent of the glaciers and discharge can be studied under the various climate scenarios. Similar to Map 12.1, Map 31.1 presents the mean available ice mass in mm of water equivalent per proxel for the IPCC regional climate trend and the baseline climate variant in the model years 2030 and 2060. The results reproduced here confi rm estimates that suggest the ice reservoir in the Eastern Alps may completely disappear as early as the second half of the century.