Climate Change Impacts on High Alpine Infrastructures: An Example from the Kitzsteinhorn (3200 m), Salzburg, Austria

Numerous rock fall events in the European Alps suggest an increasing occurrence of mass movements due to rising temperatures. In recent years particularly during extensive hot periods large numbers of rock fall events have been reported (e.g. hot summers of 2003, 2005 and 2012). Governed by climate change two major changes can be observed at the summit region of the Kitzsteinhorn, Austria: Intensive glacier retreat and changes of permafrost conditions. The combination of these two major changes leads to an increasing exposure of potentially hazardous areas and higher risks for man and infrastructure. Close to the summit, infrastructure was built in the 1960s, including a cable car station at 3029 m on a north exposed rock face w under permafrost conditions. Due to the decreasing surface area of the glacier and the deepening of the annual active layer, meter thick slabs of the slope became unstable and started sliding down slope parallel to bedding planes. In order to avoid a continuous and deep-reaching destabilization of the entire slope, an intensive rehabilitation program has been established. This program consists of short-, mid- and long-term measures with technical installations (drainage, rock support, etc.) and an intensive monitoring program (including laser scanning, continuous geophysical, geotechnical and temperature monitoring).