The “Permafrost Monitoring Switzerland (PERMOS)” is operated by the eight Swiss university institutes involved in permafrost research and financially supported by the Swiss Academy of Sciences (SAS), the Federal Office for Water and Geology (FOWG) and the Swiss Agency for Environment, Forests and Landscape (SAEFL).
The pilot phase of PERMOS was extended until the end of 2005 and will be incorporated later on into the official federal environmental monitoring. The biannual report 2000- 2002 was published in 2004 and can be downloaded from (www.permos.ch).
The Swiss permafrost community met in February 2004 in Davos. Several presentations about ongoing projects and fruitful discussions made this two-day event a big success. The following activities are reported by several institutes: At the Swiss Federal Institute for Snow and Avalanche Research (SLF), Martina Lütschg is finishing her PhD thesis entitled “A model and field analysis of the mutual influence of snow cover and alpine permafrost” in which the SNOWPACK model is used to simulate the effects of different snow cover characteristics and ground types on permafrost distribution and, based on field data, laboratory measurements and various climate change scenarios.
The stability of the snow cover in permafrost and nonpermafrost sites was analyzed by Marcia Phillips and Jürg Schweizer, using data from extensive snowpack stability tests obtained during two winters in Davos and longterm SLF avalanche statistics.
Armin Rist is analyzing new data about water in the active layer of a scree slope. In parallel, a laboratory experiment simulates the effects of water on the ground thermal regime and on slope stability. Slope stability tests were carried out in the field in collaboration with Sarah M. Springman (ETH Zurich) in summer 2004.
Three new boreholes have been added to the SLF monitoring network, making a total of 15 instrumented boreholes in alpine permafrost. Marcia Phillips continues to monitor the performance of snow-supporting structures in creeping permafrost terrain.
The Glaciology and Geomorphodynamics Group (University of Zurich) investigates the influence of groundsurface characteristics on the active layer thermal regime, in a coarse, bouldery matrix, in order to better understand the non-conductive processes. The analyses are based on data from shallow boreholes as well as from single thermistors and wind sensors placed in the active layer (S. Hanson, M. Oswald, M. Hoelzle).
Rock wall temperature data are used as a validation for the new programme TEBAL, which was developed from the former energy balance programme PERMEBAL to obtain spatial information about temperatures in rock walls. A particular emphasis was placed on investigating permafrost thawing and alpine rock walls destabilization that occurred during the hot summer of 2003. Moreover, hyperspectral remote sensing data are used for characterizing accurately surface parameters such as albedo (S. Gruber, D. Schläpfer, M. Hoelzle).
The summer 2003 rock falls and several older documented events were investigated in the perspective of permafrost degradation in steep rock walls. GIS-based models were developed to simulate these events (J. Noetzli, W. Haeberli, M.Hoelzle). Airborne GPR measurements of the spatial snow depth distribution in the Corvatsch- Furtschellas area were compared to ground measurements and with simulation results from the model TEBAL (A. Hasler, S. Gruber, R. Purves, M. Hoelzle).
In the context of the necessary assessment of the possible impacts of the predicted climatic change on mountain permafrost, the most promising tools for obtaining information about future atmospheric conditions are the Regional Climate Models (RCM). In order to use RCM data in permafrost modelling, a methodology is being established for downscaling the gridded output of RCMs, which will have a spatial resolution of 56 km (N. Salzmann, F. Paul, M. Hoelzle).
In order to better understand the intra-regional variability in rock glacier distribution, several numerical modelling approaches were applied in a study region in the eastern Swiss Alps. Among others, a dynamic model was created that allows a 4D simulation of talus-derived, rock glacier occurrence. The modelling of their spatio-temporal development and distribution shows very promising results (R. Frauenfelder, W. Haeberli, M. Hoelzle, B. Schneider, University of Basel, and B. Etzelmüller, University of Oslo).
A combined study on the development of transverse ridges on rock glaciers including high precision field surveys and physical laboratory experiments revealed that these forms are advected downstreams with a speed that approximates the overall rock glacier surface velocity. Surface speeds turned out to exhibit local maxima on top of individual ridges. In a field study on the advance mechanisms of rock glaciers a novel measurement approach allowed the determination of the ice content and the vertical velocity profile near the front. Photogrammetric measurements of speed and thickness of selected rock glaciers were continued within the PERMOS monitoring network and pointed out an increase in surface speed for most of the observed individuals (A. Kääb).
An initial explorative study of permafrost distribution in the Kazbek massif (North Ossetia, eastern Caucasus) was initiated within a project of the Swiss Agency for Development and Cooperation (SDC) in response to the catastrophic Kolka-Karmadon rock/ice avalanche that occurred on September 20, 2002 on Dzhimarai-khokh Peak (4780 m asl) (S. Zgraggen-Oswald, R. Frauenfelder, C. Huggel, A. Kääb, W. Haeberli).
The Institutes of Geography of the University of Lausanne (C. Lambiel, E. Reynard) and Fribourg (R. Delaloye) have been collaborating closely in alpine permafrost research in Switzerland for the last years. Reynald Delaloye presented a PhD thesis about mountain permafrost in peripheral areas. Thermal regime and permafrost occurrence in talus slopes are studied in low elevation sites (J. Dorthe, S. Morard) and in the alpine discontinuous permafrost belt (K. Pieraci). In order to learn more about the influence of air circulation on thermal regime, a shallow borehole (about 20 m) will be drilled and instrumented in autumn 2004, for the first time in a low altitude talus slope (at 1550 m asl in the Combe de Dreveneuse, Valais Prealps).
Surface displacements are monitored at some alpine permafrost features (active and inactive rock glaciers, frozen deposits in Little Ice Age glacier forefields, talus slopes) using GPS (E. Perruchoud) and photogrammetry (J.-P. Dousse, in collaboration with A. Kääb and R. Lugon, at K. Bösch, Institute Sion). GPS surveys have been carried out at six sites since 2000. Global accelerations were observed between 2000 and 2003. Surface velocities seemed to keep increasing between 2003 and 2004. The photogrammetry study of the Rechy rock glacier (Valais) has been carried out since 1986 on the basis of high resolution aerial photographs taken every four to five years.
Permafrost thermal monitoring is conducuted in two boreholes (Lapires and Gentianes). Using the building site of a snow supporting structure, a new shallow borehole (20 m) was drilled in bedrock in summer 2004 (Pointe du Tsaté, 3070 m asl). BTS and GST (ground surface temperature) monitoring have gone on at 15 sites since 1996 (for the longest BTS series) and 1997 (for GST). Some of these measurements are included in PERMOS. One of the most interesting results came from an inactive rock glacier (Alpage de Mille, Valais Alps), where the nine-years BTS series indicated a winter ascending air circulation throughout the whole rock glacier. Assessing the thermal effect of such a process is a challenging perspective for further research.
Daniel VonderMuehll (Daniel.VonderMuehll@unibas.ch)