Climate Change Impacts on Soil Erosion and Sediment Delivery to German Federal Waterways: A Case Study of the Elbe Basin

Climate change is an important driver of soil erosion and sediment delivery to water bodies. We use observation data from 193 locations in the Elbe River basin as well as spatially distributed erosion rates and sediment delivery simulated in the WaTEM/SEDEM to identify current erosion hotspots and to assess the impact of climate change on future erosion and sediment delivery. We further quantified the uncertainty of the modelling approach by using an ensemble of 21 combinations of global and regional climate models, different emission scenarios and stochastic erosion modelling. Erosion rates are highest on hilly arable land in the central part of the basin as well as in the northeast of Bohemia. Despite considerable differences between climate models and emission scenarios and considerable uncertainties of the erosion model, a future increase in soil erosion and sediment delivery is highly likely. Using the median of climate models and behavioral erosion models, this increase can be up to 14% higher in the far future (2071-2100) than in the reference period (1971-2000) using RCP 8.5. The increase is highest in the Czech part of the basin.