Improving the Aerosol-cloud-radiation Interactions in WRF-Chem-Solar and its preliminary application in China

The Weather Research and Forecasting model with solar extensions (WRF-Solar) has demonstrated potential and reliability in employing an aerosol-aware microphysics scheme as a moderate-cost alternative for aerosol-cloud-radiation and solar power simulations. However, it has not been integrated with any aerosol model due to computational cost considerations. In this study, we fully couple the Thompson and Eidhammer aerosol-aware microphysics scheme with the Goddard Chemistry Aerosol Radiation and Transport (GOCART) model, incorporating online aerosol-cloud-radiation interactions into the WRF-Solar model. We then evaluate its performance on shortwave radiation in China in March 2021. The results show a general improvement in the model's Aerosol Optical Depth performance across most areas in China, thereby enhancing the simulation of clear-sky global horizontal irradiance (GHI). The most significant enhancement is observed in northern regions, with reductions of 24% in RMSE and 44% in BIAS. Subsequently, cloud properties and all-sky GHI are examined, revealing improvements in almost all areas except Tibet, with the most notable improvement in the Western region (56.18% reduction in BIAS for all-sky GHI). The observed underestimations in northwest areas are attributed to the overestimations of dust. This study not only provides better GHI forecasting results but also deepens the understanding of aerosol-cloud-radiation interactions in climate prediction