Mountain permafrost and recent Alpine rock-fall events: a GIS-based approach to determine critical factors

• Main Authors: Noetzli, J, Hoelzle, M, Haeberli, W
• Other Authors: Phillips, M, Phillips, M ( M ), ( )
• Format: Book Part
• Language: English
• Published: Balkema Publishers 2003
• Subjects: Institute of Geography; 910 Geography & travel; Cold Mountain; permafrost
• Online Access: https://www.zora.uzh.ch/id/eprint/33321/; https://www.zora.uzh.ch/id/eprint/33321/9/Noetzli_Hoelzle_Mountain_Permafrost_2003.pdf; https://doi.org/10.5167/uzh-33321

Glacier retreat and permafrost changes, as related to climate change, are supposed to affect stability conditions of steep rock walls in cold mountain ranges. Several rock-fall events, which have occurred in the European Alps during the 20th century, are possibly related to warm permafrost. This study undertakes a systematic parameterization of rock-fall events in order to increase information about thermal and topographic conditions under which rock instabilities develop in areas of mountain permafrost. Thermal conditions of historically documented starting zones are parameterized by applying either empirical rules or GIS-based spatial models; slope is derived from DTMs. Despite the relatively small number of events documented so far (around 20), the first results presented clearly indicate that the factor ‘permafrost’ must be considered in connection with rock-falls from high mountain slopes.