Projected changes in extreme precipitation characteristics forCentral Eastern Germany (21st century, model-based analysis)

Changes in frequency, duration and/or intensity of extreme precipitation events, such as heavy precipitation or drought, profoundly impact both society and the natural environment. Regional climate models are valuable tools to assess any future progress of such events, and to complement the development of regional and local adaptation and mitigation strategies-here for the model region Dresden within the REGKLAM project. Multi-model approaches may alleviate some of the problems related to uncertainties of projected changes. The bandwidth of future climate conditions in Central Eastern Germany has been estimated, using 12 regional climate projections in daily resolution as simulated within the EU-project ENSEMBLES (emission scenario A1B). Validation of the model runs against an observation data set displayed significant difficulties of the models to describe the regional precipitation characteristics. Shortcomings are particularly obvious in realistically simulating dry period characteristics, likely due to an overestimation of precipitation totals. Most models agree in the projection of more frequent and longer-lasting drought events during summer, while wet phase frequency and persistence is projected to increase in winter. Extreme precipitation events (99th percentile) are likely to increase by the end of the 21st century in most seasons-even in summer, despite projected decreasing average precipitation. The suggested display of all individual model results allows comparing the characteristics and the trend behaviour of the individual regional climate projections. This supports selecting the suitable model(s) for specific impact modelling demands.