Changes in future soil erosion rates are driven by climatic conditions, land use patterns, socio-economic development, farmers’ choices, and importantly modified by agro-environmental policies. This study simulates the impact of expected climatic and land use change projections on future rates of soil erosion by water (sheet and rill processes) in 2050 within the agricultural areas of the European Union and the UK, compared to a current representative baseline (2016).

We used the Revised Universal Soil Loss Equation (RUSLE) adjusted at continental scale with projections of future rainfall erosivity and land use change. Future rainfall erosivity is predicted using an average composite of 19 Global Climate Models (GCMs) from the Coupled Model Inter-comparison Projects (CMIP5) WorldClim dataset across three Representative Concentration Pathways (RCP2.6, RCP4.5 and RCP8.5). Concerning future land use change and crop dynamics, we used the projections provided by the Common Agricultural Policy Regional Impact Analysis (CAPRI) model.
By 2050, mean soil loss rates due to water erosion may increase by 13–22.5 % in agricultural areas of the EU and the UK compared to the 2016 baseline. Those projections have been shaped using a combined model framework of both land use and climate change. Compared to land use change, climate change showed a dominant effect on future soil erosion projections. To ensure comprehensiveness, we have considered climate projections for the year 2050 from 19 models applied in the EU plus the UK for three different RCP scenarios. Although the RCP2.6 and RCP4.5 climate change scenarios could result in similar mean values for the entire study area, we found consequentially different spatial variations in the patterns of soil loss (between 2016 and 2050). The less aggressive mitigation pathway RCP8.5 climate change scenario is alarming as it will aggravate soil loss in 84 % of the study area and increase the soil loss rates by at least 45 % in Western Europe. The Mediterranean basin shows smaller increases mainly due to the mixed impact of climate change on rainfall erosivity in this region.

The future projections of soil loss rates could be at least 3% higher if land use changes were ignored. In this study, the main drivers of land use change between 2016 and 2050 were crop composition dynamics, the transformation of cropland to grasslands and the shrinkage of EU agricultural area by 3.9 %. Therefore, it is recommended that projections of soil losses due to water erosion should consider both a wide range of climate change scenarios but also future land use changes.

As agro-environmental policies are the only mechanism to mitigate the future negative trend of soil loss in the EU, we performed a policy relevant scenario analysis. Among the scenarios, we included the uptake of management practices relevant to green soil coverage and minimum soil disturbance and have some quotations in the future Common Agricultural Policy (post-2020 CAP). The most effective policy instrument is to link CAP incentives to environmental performance in a targeted way. However, the application of soil conservation measures such as cover crops and reduced tillage should include at least 50 % of the hotspots (i.e., where soil losses exceed 5 t ha−1 yr−1) to neutralize the future impact of climate change on water erosion. The post 2020 Common Agricultural Policy and other EU policy developments (EU Green Deal) may include a stronger soil conservation package with quantitative targets to mitigate the important soil erosion increase which is expected due to climate change in Europe.