Potential future increase in extreme one-hour precipitation events over Europe due to climate change

摘要

In this study the potential increase of extreme precipitation in a future warmer European climatenhas been examined. Output from the regional climate model (RCM) HIRHAM4 covering Europe hasnbeen analysed for two periods, a control period 1961–1990 and a scenario 2071–2100, the latternfollowing the IPCC scenario A2. The model has a resolution of about 12 km, which is uniquencompared with existing RCM studies that typically operate at 25–50 km scale, and make thenresults relevant to hydrological phenomena occurring at the spatial scale of the infrastructurendesigned to drain off rainfall in large urban areas. Extreme events with one- and 24-hour durationnwere extracted using the Partial Duration Series approach, a Generalized Pareto Distribution wasnfitted to the data and T-year events for return periods from 2 to 100 years were calculated fornthe control and scenario period in model cells across Europe. The analysis shows that there willnbe an increase of the intensity of extreme events generally in Europe; Scandinavia will experiencenthe highest increase and southern Europe the lowest. A 20 year 1-hour precipitation event willnfor example become a 4 year event in Sweden and a 10 year event in Spain. Intensities for shortndurations and high return periods will increase the most, which implies that European urbanndrainage systems will be challenged in the future.