The Swiss Federal Institute for Snow and Avalanche Research belongs to the Swiss Federal Research Institute on Forest, Snow and Landscape (WSL). WSL falls under the Board of the Swiss Federal Institutes of Technology. WSL/SLF conducts basic and applied research on the environment, sustainability, and risks from natural hazards, and are represented in the UNESCO supported International Consortium on Landslides (ICL). Over 450 staff from a wide range of natural, engineering, and social sciences work in three research departments: forest, landscape, and natural hazards. The Natural Hazards Department has 150 staff researching mainly in the fields of snow physics, snow avalanche formation and dynamics, avalanche prevention and risk management for natural hazards.
Snow avalanches are a major natural hazard in Switzerland where half of the country – populated by about 1.5 mi people – is mountainous terrain where snow avalanches can occur. Although there is a long tradition in snow avalanche research and a lot of avalanche protection works are in place, it is still impossible today to precisely predict the location and time of a snow avalanche. Snow avalanche release is the result of several failure processes spanning several orders of magnitude (0.1 mm to 100 m). Snow – the material that fails – has a highly complex microstructure (that changes with time) and the snow mechanical properties are strongly temperature and rate dependent. At all scales of relevance in the failure process disorder plays a crucial role, e.g. for failure initiation as well as for fracture propagation. We therefore aim a better understanding of the role of disorder in avalanche formation at various scales in order to improve our ability to model the failure process across scales. Lab and in particular field experiments in the new test site Wannengrat will be combined to increase the possibility to predict snow avalanches. The TRIGS project will help to reach this aim and offers the unique opportunity for close collaboration with research groups that also focus on triggering of instabilities. The group has a long tradition and strong competence in knowledge transfer, teaching and consulting. It particularly focuses on improving avalanche forecasting – at various levels – and will continue to act as a link between research and practice.

Team Leader: Jürg Schweizer is a senior researcher at SLF and leads the research group “Formation of Alpine Natural Hazards”. He has studied environmental physics at ETH Zurich, graduated with a Ph.D. in glaciology, and joined the Swiss Federal Institute for Snow and Avalanche Research SLF in Davos in 1990. His research focuses on snow mechanics, avalanche formation, snow slope stability evaluation and avalanche forecasting. Furthermore, he is responsible for the Swiss educational program for avalanche professionals (IFKIS). In the last ten years he has authored more than 20 expert reports about avalanche accidents for courts. A detailed CV is available here.

Additional participants

Alec van Herwijnen: He studied experimental physics as well as meteorology and physical oceanography at the University of Utrecht in the Netherlands. Following this, Alec went to Canada to do a PhD in avalanche mechanics at the University of Calgary. His research involved observing fractures in weak snowpack layers with a portable digital high speed camera. He also helped developed a fracture characterization scheme for snowpack stability tests, which is now widely used by avalanche professionals in Canada. In 2007 Alec moved to Davos in Switzerland to continue studying avalanche initiation at the SLF. The aim of his project is to monitor slope instability by instrumenting a snow slope that is known to avalanche frequently with an array of acoustic sensors. This should allow to identify precursor events and the type of failure (from local damage to global slope failure).

Sascha Bellaire: PhD student at the SLF since march 2006. The aim of his work is the quantification, interpretation and modelling of snow cover spatial variability on slope scale with regards to the avalanche formation process. This research will be done at the new experimental site Wannengrat, a region known for its high avalanche activity. The test site is instrumented with several weather stations which record meteorological conditions during weak layer formation, and provide input data for different models. Sascha studied meteorology at the University of Hamburg. For his master thesis he worked on a new stability index, combining structural and mechanical properties of the snow, for the snow cover model SNOWPACK.

Ingrid Reiweger: She studied theoretical physics at the Technical University of Graz, Austria. For her masters thesis she worked on the contractor renormalization group method to calculate strongly correlated many particle systems. She started her PhD on fracture initiation in weak snow layers in August 2006 at the SLF in Davos. Weak snow layers are a necessary prerequisite for slab avalanche formation. The goal of her work is to determine the mechanical properties of these in order to better understand the fracture initiation process. This will be done by performing shear experiments on artificially created layered snow samples under controlled conditions in a laboratory. to the experiments a model is developed to describe the weak layer’s reaction to a layer parallel force. WSL/SLF researcher.