Summary
Solar radiation modification (SRM) is a proposed way to reduce climate risks, but its effects in Central China are uncertain. Using climate model simulations for the late 21st century, this study examines how SRM could change rainfall amount, intensity, and extremes. High-resolution observations were used to improve the models. Strong warming scenarios increase rainfall and extremes, while SRM reduces these increases, making conditions closer to moderate scenarios. However, SRM effects vary by region, with different rainfall responses across Central China.
Abstract
Solar Radiation Modification (SRM) has been proposed as a potential strategy to mitigate climate extremes and hydrological disasters, but its effects on Central China remain unclear. This study assesses the impacts of SRM on precipitation patterns and extremes in Central China using simulations from the Geoengineering Model Intercomparison Project Phase 6 (GeoMIP6). Two SRM scenarios (G6solar and G6sulfur) were employed alongside baseline socio-economic scenarios (SSP245 and SSP585) for the late twenty-first century (2080–2099), with the historical period (1995–2014) serving as a reference. The China High-Resolution Land Temperature and Precipitation Dataset (HRLT), a high-resolution observational dataset, was used for downscaling and bias correct the GeoMIP6 models via bilinear interpolation and linear scaling methods. Eight precipitation indices were analyzed to evaluate changes in total precipitation, intensity, and extreme weather events under different scenarios. Results show that SSP585 leads to substantial increases in total precipitation, daily intensity, and precipitation extremes, particularly in northern and southern regions, while SSP245 exhibits more moderate and less intense changes. SRM scenarios effectively offset the more intense precipitation increases seen under SSP585, aligning patterns more closely with SSP245, with G6sulfur showing greater and more spatially uniform suppression than G6solar. However, significant spatial heterogeneity in SRM impacts persists, with contrasting trends in different regions and precipitation indices. G6solar shows stronger reductions in wet periods in southern regions like Jiangxi and Hunan, where monsoonal rainfall dominates, while G6sulfur leads to increased precipitation in northern areas such as Shanxi and Henan, driven by sulfate aerosol-induced atmospheric circulation changes.
