Impact of climate change on soil erosion — A high-resolution projection on catchment scale until 2100 in Saxony/Germany

This study investigates changes in erosion rates at high temporal and spatial resolution for three example catchments in West, North and East Saxony/Germany under climate change. The study is based on the A1B IPCC-scenario and model outputs of four models: ECHAM5-OPYC3 (general circulation model), WETTREG2010 (statistical downscaling climate model), METVER (agricultural model for calculation of daily initial soil moisture) and EROSION 3D as a process-based soil erosion model. Simulations were run for measured and projected single rainstorm events at a temporal resolution of 5min. Soil loss was simulated for two future periods from 2041 to 2050 and 2091 to 2100, respectively. Results were compared to simulated soil loss based on 10years of measured climate data from 1989 to 2007. Expected changes in land use, soil management due to changed crop rotation and shifted harvest date are taken into account as scenario studies.Outputs of the regional climate model show that the total number of rainstorms with intensities≥0.1mm/min is decreasing in future while rainfall intensities are increasing. Periods of heavy rainstorms will mostly shift from summer to autumn. While the total amount of annual rainfall is decreasing and the duration of sunshine is strongly increasing, soils become drier. Dry periods will appear more often in late autumn.Results of the simulations with EROSION 3D quantify the impacts of climate change on erosion rates. Climate change will lead to a significant increase of soil loss by 2050 and a partial decrease by 2100. Not adapting soil management and land use will aggravate erosion rates.The impacts of land use, soil management and soil properties on soil erosion by water are higher than the effects of changed precipitation patterns. Current soil protection measures are suitable for soil conservation under conditions of a changed climate.