Large-scale modelling of soil erosion by water and potential Global Change impacts in the Upper Danube basin DANIEL WALDMANN & WOLFRAM MAUSER Department of Geography, Ludwig-Maximilians University Munich, Luisenstrasse 37, 80333 München, Germany d.waldmann@iggf.geo.uni-muenchen.de Abstract The project GLOWA Danube investigates regional scale implications of climate change on the water cycle. The decision support system DANUBIA integrates models of natural and social sciences. The erosion component within DANUBIA simulates soil erosion by water on a spatial resolution of 1 km² and a temporal resolution of 1 hour. This paper briefly describes the design of the soil erosion module and presents a model validation based on the analysis of results for the reference period (1990 - 2005). Furthermore the results of the simulated GLOWA-Danube Climate Change scenario runs (2011 - 2060) are interpreted with special regard to influences of changed precipitation patterns on soil erosion. Keywords soil erosion; modelling; global change; precipitation; GLOWA Danube; scenarios INTRODUCTION One of the major factors controlling soil erosion by water is the climate, epecially precipitation. Changes in absolute precipitation volumes, but moreover changes in seasonal precipitation distribution and temporal precipitation patterns of single events are of relevance. The IPCC (Christensen et al., 2007) mentions a possible increase in extreme events in summer in Central Europe. Because often only a few heavy precipitation events are responsible for the majority of soil loss within a year (cf. e.g. Nearing et al., 2005), this statement leads to the conclusion that soil erosion risk in Central Europe might increase with changing climate. The project GLOWA Danube investigates impacts of Global Change and Climate Change on the regional scale within the Upper Danube basin. The framework DANUBIA allows for coupling models of natural and social sciences (Barthel et al., 2008). Future scenarios of climate change, based on the outputs of regional climate models are used for driving the models. Within DANUBIA the modular hydrological model PROMET simulates the water and energy fluxes of the land surface. The erosion module of PROMET has been developed by the lead author and is used in this paper to examine potential implications of changing precipitation patterns on soil erosion by water. STUDY AREA AND DATA The study area of the project GLOWA-Danube is the Upper Danube basin. The catchment area is 76,653 km², covering large parts of southern Germany and the Austrian Alps. The heterogeneous catchment is characterised by strong meteorological (mean annual temperature: -4.7 °C to +9 °C, mean annual precipitation: 650 mm to >2000 mm) and altitudinal (287 to 4049 m a.s.l.) gradients (Ludwig et al., 2003). The main land cover in the catchment consists of forest (40%) and grassland (27%), followed by arable land (23%). Minor areas are covered by artificial surfaces and rock (4% each), water bodies and glaciers sum up to 1% each. Cereal production takes place on over 50% of the total arable land in the basin and is widespread over the whole