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Weather and climate extremes and drought

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Weather extremes, such as droughts, heatwaves and storms, are becoming more frequent in Switzerland as a result of climate change. Our research is creating a knowledge base for better forecasts and adaptation strategies.


Events which differ markedly from an average value are designated as extreme; examples include the summer drought of 2015 and the August flooding of 2005. It is evident that more very warm days and fewer very cold nights are now being recorded in Switzerland. On a global scale, heat extremes and heavy precipitation are expected to become more frequent and more intense, but extreme cold will be less pronounced. This has consequences: in the 2016 report "Brennpunkt Klima Schweiz" (Focus on Swiss Climate), more than 70 climate researchers concluded that "weather and climate extremes such as heatwaves, periods of drought or severe precipitation and other related natural hazards are among the greatest direct challenges which Switzerland faces due to climate change".

Droughts and Forest Fires

At the WSL, we are focused on the early detection and impact of such extreme situations on ecosystems and the population. For example, we manage in cooperation with the federal offices of FOEN (Federal Office for the Environment) and MeteoSwiss the project Drought-CH. This is an information platform for the early detection of drought; it is aimed at municipalities, hydroelectric power plants, and farmers.

The risk of forest fires rises with increasing drought. The WSL also collects data on these events and develops methods for the prevention of forest fires.

Climate change means that trees germinating today will be living in an altered climate by the time they reach middle age. Forests will no longer be able to perform important functions such as water treatment or protection from avalanches at the same level; therefore, expensive protection structures or reforestation will be necessary. We provide an information basis so that forestry services, forest managers and policymakers can correctly assess the climate risks and the adaptability of forests, and take effective adaptation measures (see also Forests and Climate Change).

Impact on Society

Floods are particularly perilous when they affect delicate infrastructures such as nuclear power plants. These must also be safe in the case of extremely rare events such as those which occur every 100,000 years. Within the scope of the EXAR project, we are estimating the danger of such extreme floods in the Aare and the Rhine.

The impact of extreme situations on the economy and society can be serious. We are therefore seeking political and economic adaptation strategies. From this, we develop recommendations, for example for mountainous areas when an important source of income is lost when there is a lack of snow for winter tourism.



Dossier: drought in Switerland

Drought is a serious threat to people and the natural environment. We conduct research on forecasting and managing drought.