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In Switzerland, natural hazards such as avalanches, landslides, rockfall, debris flows, flooding and forest fires can cause considerable damage. Through our research and services, we help to protect people from such dangers.


In Switzerland, 23 people are killed on average each year by avalanches alone, flooding and mass movements cause damage amounting to an average of CHF 300 million per year. As the population continues to grow, more and more buildings are located in at-risk areas. When glaciers melt and permafrost thaws as a result of climate change, this threatens to set in motion enormous quantities of soil, rock and scree.

We look into how different natural hazards arise, how far, how quickly and how vigorously they develop, and how people can protect themselves, e.g. through spatial planning, reliable forecasting or technical protective measures. Thereby we lay the scientific foundations for risk analysis and for evaluating whether protective measures and warning systems are effective and economical.

As well as scientific and engineering research, this requires economic and social analysis, and close cooperation between the various actors. After all, dealing with natural hazards present politics, government and society with the challenge of finding widely accepted and economically viable risk reduction strategies.

Observation and simulation

In order to understand the processes of natural hazards in detail, we run facilities which are unique worldwide. In the Illgraben (VS), for example, we observe naturally occurring debris flows with various measuring instruments. As part of field experiments, we investigate the dynamics of avalanches, debris flows, rockfall and landslides under realistic conditions. At our site in Cadenazzo (TI) we record and analyse forest fire events, develop methods and concepts to evaluate the risk of forest fire, and determine their consequences for ecosystems such as protection forests.

Thanks to this measurement data, we now understand better than ever how these natural hazards arise, and are able to simulate the processes within them in increasingly precise computational models. This is useful for developing protective measures and hazard maps.

Forewarned and informed                                                                           

When it comes to warning and prevention systems, we play an important role nationally as well as internationally: in winter, the avalanche warning service at the WSL Institute for Snow and Avalanche Research SLF publishes the well-known avalanche bulletin twice a day. Our hydrologists are involved in warning the public about instances of flooding and severe drought.

We make our data and findings available to the public on internet platforms and as apps, so that crisis managers can access the information quickly in an emergency. We also publish leaflets and brochures.


Focus Areas

Dependent on artificial snow: ski slope in Brigels (photo: WSL)

Adaptation to climate change

We explore how the population, politics and economic sectors such as tourism can meet the challenges of climate change.

WSL Research Programme Extremes

Exploring Extremes

We research events that occur rarely and irregularly, but can nevertheless have a massive impact on the environment and society.

Zwei mit mehreren Personen besetzte Schlauchboote fahren durch die von Hochwasser überfluteten Gassen in einer Stadt.

Swiss flood and landslide damage database

Since 1972, we have been systematically recording the damage caused by storms on the basis of newspaper reports, on behalf of the federal government.

CCAMM – Climate Change Impacts on Alpine Mass Movements

CCAMM: Climate change and mass movements

We study the effects of climate change on mass movements in order to better assess risks and develop adaptation strategies.

Research Centre CERC

We develop solutions to problems that arise in mountain regions due to the consequences of climate change, extreme events and natural hazards



The warm and dry weather in 2022 and hail in 2021 gave the bark beetle a boost again after a brief respite.

A 50-year comparison shows that drought deficits are increasing in Switzerland due to a lack of snow.

A new study determined for the first time the water availability in forests and the seriousness of droughts for Swiss forests.

Why do Scots pines keep dying en masse in dry Alpine valleys, even without extreme drought? WSL researchers have now solved the mystery.




Caviezel, A.; Sanchez, M.A.; Lu, G.; Christen, M.; Bartelt, P.; Wendeler, C.; Lanter, A., 2020: Full scale testing of rockfall nets under realistic conditions. In: Li, C.C.; Ødegaard, H.; Høien, A.H.; Macias, J. (eds), 2020: ISRM international symposium - EUROCK 2020. ISRM international symposium Eurock 2020 - hard rock enigeering, Trondheim, Norway. (7 pp.).