Analysis of decadal precipitation changes at the northern edge of the Alps

Abstract

Precipitation data from four weather stations in Bavaria, Germany, situated at the northern edge of the Alps have been evaluated for the period 1901 to 2019. Decadal changes have been computed as sliding 30-year averages and as the difference between the 30-year periods 1990–2019 and 1901–1930. The annual precipitation at these four stations increases, fitting in magnitude roughly to the temperature increase in the course of global warming. The number of dry days slightly increases as well as a consequence of a northward shift of the storm tracks over Europe. Due to these two features the precipitation intensity on wet days increases. The increase in maximum daily precipitation amounts is less than the increase in the annual precipitation amount. The observed maximum daily precipitation in the full four datasets is 138.5 mm at the station Hohenpeißenberg in 1999. The length of dry spells is increasing at three of the four stations as well. The overall observed precipitation patterns fit to the findings of regional climate model simulations for future climate scenarios for this region. Thus, they can be interpreted as signs that climate change is well underway in Southern Bavaria as it is in most places of the world.