Notable Radiative Effects of Brown Carbon in China Haze

Abstract Brown carbon (BrC), a light‐absorbing organic aerosol, remains poorly constrained in climate models due to unclear sources and formation pathways. In this study, we developed a BrC parameterization scheme by applying multivariate regression to observational data in China, relating BrC concentrations to organic carbon, meteorological conditions, and chemical variables. This scheme was implemented into the WRF‐Chem model to simulate BrC distributions and radiative effects during a haze episode from 1 January–12, 2019. The simulation revealed BrC concentrations ranging from 2.20 to 69.38 μg/m 3 (mean: 11.63 μg/m 3 ), with elevated values in the Beijing‐Tianjin‐Hebei region and Central China. BrC absorption notably decreased surface shortwave radiation by 7.07 W/m 2 and increased atmospheric shortwave radiation by 0.73 W/m 2 , inducing non‐negligible land surface cooling, positive pressure anomalies, and higher near‐surface humidity. These findings underscore the notable radiative influence of BrC in haze‐prone regions of China, with implications for local climate and atmospheric dynamics.