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On 25 November 1992 about 30 scientists and members of the Swiss Coordinating Group on Permafrost of the Swiss Academy of Sciences met at the Laboratory ofHydraulics, Hydrology and Glaciology (VAW) of the Swiss Federal Institute of Technology, Zurich (ETHZ). Short reports were given on current permafrost research in polar and alpine areas.

M. Hoelzle (VAW) summarized results of D.C. resistivity soundings carried out on rock glaciers and ice-cored moraines of northwest Svalbard in cooperation with the Geographical Institute of the University of Oslo. K. Dettwiler and N. Ritter from the Geographical Institute, University of Basel, gave an outline of ongoing climatological and geoecological permafrost investigations in Svalbard as part of the German/Norwegian/Swiss Liefdefjorden Expeditions 1990, 1991 and 1992. Concerning the Alps, O. Antonson (Paul Scherrer Institute, Villigen) discussed gas analyses on core samples from the Murtèl drilling, D. Vonder-Mühll (VAW) described gravimetric measurements on the Murtèl rock glacier, and W. Haeberli (VAW) presented time series of borehole temperatures from the same place.

Borehole deformation measurements in the permafrost of Pontresina-Schafberg were analyzed by S. Wagner (VAW), and F. Keller (VAW) illustrated snow-permafrost interactions from extensive field experiments in the Upper Engadin. The distribution pattern of permafrost in selected areas of the Western Alps is being investigated by a research group of the Geographical Institute of the University of Lausanne (P. Schoeneich). Attempts are being made to numerically model the influence of Ice Age glaciers and permafrost on ground temperatures and groundwater conditions in the Swiss Plateau (C. Speck, VAW). Hazards from debris flows starting in steeply inclined permafrost terrain above Randa, Valais, are being dealt with by M. Zimmermann (Geo 7, Bern).

Preliminary pollen analysis by botanists from the University of Basel of organic matter found in the uppermost part of the Murtèl permafrost core appears to confirm that the ground ice within the active rock glacier indeed dates from the earlier part of the Holocene, as estimated earlier on the basis of thermal and flow considerations. Permafrost in starting zones of snow avalanches and corresponding problems relating to avalanche protection are being investigated by VAW and the Swiss Federal Institute for Snow and Avalanche Research, Weissfluhjoch/Davos, in cooperation with federal and cantonal authorities. Attempts continue to build a network for monitoring the long-term evolution ofpermafrost in the Swiss Alps. Warming of Alpine permafrost since the late 1980s is observed in the Murtèl borehole and appears to have accelerated by a factor of about 5 to 10 as compared with reconstructed secular permafrost warming (about 1°C/century).

Thawing of frozen ground as inferred from high-precision rock glacier photogrammetry seems to have markedly accelerated also, in 1980-1990, as compared with 1970-1980. Computer simulations of changing permafrost distribution patterns and ground temperatures are developed at VAW within the framework of the Swiss National Research Program on Climate Change and Natural Catastrophes. Geographical Information Systems have found wide application for estimating permafrost occurrence on the basis of digital terrain information. Corresponding algorithms are presently being improved by using the growing data base from field evidence in combination with energy balance considerations.

Prepared by Wilfried Haeberli