Seasonal Variation of Daily Extreme Precipitation in Switzerland

Extreme weather events, such as the flood episode in Switzerland in August 2005, deeply affect our society through their adverse impact on human life, infrastructure and economy. The assessment of their return periods and values is crucial for accurate planning of infrastructure and prevention measures. It is done by means of the statistical tools of Extreme Value Theory, which assumes stationarity of the precipitation process. So far, only yearly return levels are computed operationally, yet monthly values are desirable for many applications but still not as reliable as necessary.