Prediction of rainfall erosivity in Eastern Monsoon Region in China based on CMIP6 models

This study forecasts the rainfall erosivity (RE) in the Eastern Monsoon Region (EMR) of China from 2030 to 2100, utilizing downscaling and bias correction of 10 Global Climate Models (GCMs) from CMIP6 under three emission scenarios (low: SSP1-2.6, medium: SSP3-7.0, high: SSP5-8.5). It also investigates the contribution rate of RE produced by different precipitation levels to the overall RE. Findings include: (1) The multi-model ensemble (MME) performs better than individual models, with overestimations in North China and underestimations in Northeast China and East China. (2) Future annual RE is projected to increase. In the near term (2030–2064), it will rise by 34.75%, 25.09% and 34.62% under SSP1-2.6, SSP3-7.0, SSP5-8.5 scenarios respectively. In the long term (2066–2100) the RE will increase by 41.24%, 43.51%, and 55.43% under the same scenarios. A continuous increase in emissions is projected to initially decrease RE in the near-term, followed by an increase, but consistently raise RE in the long-term. (3) RE and emission scenario relationships vary regionally. In the southern regions, East China and South China (EC and SC), annual RE decreases and then increases as emissions rise. Conversely, in the northern regions, Northeast China and North China (NEC and NC), higher emissions consistently lead to higher erosion. This is attributed to differing aerosol and greenhouse gas impacts on precipitation. (4) Heavy RE dominates in the entire EMR and its contribution to total RE is expected to rise due to increasing extreme precipitation. (5) Near-surface temperature (tas) is the most influential factor for RE, especially for large and heavy RE, with positive correlations that intensify under higher emissions. This study offers insights for anticipating future erosion risks and guiding soil and environmental policy in a warming climate.