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We investigate snow, ice and permafrost in relation to their importance as a natural resource for winter tourism and as a source for drinking water and hydropower. We also research avalanche formation processes as well as the exchange processes between soil, snow and the atmosphere.


Although Switzerland is regarded as the reservoir of Europe, it cannot be relied upon to deliver the right amount of water in the right place at the right time. Under the influence of climate change, such variances will become even more pronounced in future. We are investigating hydrological and climatological issues, and in particular the relationships that exist between snow, runoff, climate and natural hazards.

Natural snow cover acts as a giant water reservoir, supplying water well into summer, and ensuring that hydro-electricity can then still be produced. We develop models to estimate how much water is stored in the snow and thus how much melt water is likely. These models are also useful in assessing the impact of climate change on the hydrological system. They yield valuable information that not only helps the electricity industry make decisions, but also helps to improve forecasts of spring flooding.

Permafrost: permanently frozen ground

Permanently frozen ground or permafrost covers around 6% of the Swiss Alps and occurs primarily above 2400 m. Permafrost can consist of all kinds of frozen ground (rock, scree slopes, moraines etc). Since 1996, boreholes have been drilled and fitted with measurement instruments in more than twenty permafrost locations in the Swiss Alps. Our permafrost measurement network supplies essential data on the state of the permafrost and aids the understanding of the complex interaction between the ground surface and underlying substrates.

Snow as a natural hazard

Among our core activities, serving the purpose of safeguarding the population against natural hazards in the long term, is the research it conducts in the disciplines of avalanche formation, dynamics and protection. An already thorough understanding on how avalanches are formed enables the SLF to publish reliable alert bulletins. This way, safety personnel of ski resorts and mountain villages as well as winter tourists and free riders are warned against impending danger. However, more research is required to find out exactly when and where an avalanche is triggered. For an overview of the current snow and avalanche situation, please check

Snow as a substance

Snow is a porous material composed of ice and air which undergoes constant change due to external influences. Even for porous materials with non-mutable microstructures, science provides only very limited theories about the relevant mechanical and thermal properties. To analyse the microstructure of snow, therefore, special experimental and theoretical concepts are required. Only in this way can any progress be made in avalanche forecasting and climate research.

The core topic of the team "Snow Physics" is structure and property of snow and firn at different scales. Research is done in a cold laboratory with micro-computed tomography (micro-CT), nature-identical snow production and our in-house designed snow-breeders as well as in the field with natural snow.

Snow – an important resource for winter tourism

Because of its winter tourism, Switzerland is extremely dependent on snow. Snow depth measurements are therefore used not only for avalanche warning purposes, but also to examine the influence of climate warming on the snowpack.

In order to quantify such changes and correctly classify individual winters with very little or large amounts of snow, long-term serial studies are very important. Together with MeteoSwiss, we maintain a network of more than 100 observers who measure the fresh snow and overall snow depths daily from October to May. he majority of these long-term serial measurements date back around 50 years, but individual stations have been taking measurements for more than 100 years.

We also participate in cooperative commercial projects like energy saving production of technical snow, conserving snow over the summer and the efficient preparation of ski slopes. Also, we conduct in-depth studies on the complex system “man – sliding material – snow”.



Glaciers and polar ice sheets

We study polar regions and Alpine glaciers in order to understand climate change and evaluate the future water reserves.


Snowpack plays a key role in local climate and water storage in alpine regions. Its structure is a decisive factor in avalanche formation.

Snow sports

Nowadays, success in snow sports depends on more than the athletes' performance. The material and knowledge of the snow are important factors too.


The term ‘permafrost’ refers to permanently frozen ground. If it thaws, there is a risk of natural hazards like rockfalls or debris flows.


Research into avalanche formation, dynamics and protection is part of our remit. Our most important product is the avalanche bulletin.

Snow and climate change

Due to more frequent rainfall instead of snow and an earlier snow melt snow cover duration and maximum snow depths are declining in the Alps.

Water resources and energy

We examine the causes and effects of fluctuations in water availability, e.g. on hydropower.



The SLF maintains the stations of the Intercantonal Measurement and Information System IMIS, which provides important data for avalanche warning.

ICOS Ecosystem Station Davos. Photo: Matthias Paintner

The ICOS network records carbon fluxes in order to mitigate climate change. Two stations are located in Switzerland.

Free online course with participation of SLF scientists on satellite- and drone-based observation of the cryosphere. Join now!

The Akademik Tryoshnikov is anchored at Cape Baranov, Bolshevik Island, bringing supplies to the Russian research station. Photo: Fabian Fopp.

WSL doctoral student Joël Rüthi spent five weeks aboard an icebreaker. A logbook contribution about the search for Arctic soil microbes.