LAUSR

The impacts of anthropogenic emissions on the reduction of source‐specific equivalent black carbon (eBC) aerosols and their direct radiative effects (DREs) were investigated during the lockdown of the coronavirus outbreak in a megacity of China in 2020. Five eBC sources were identified using a hybrid environmental receptor model. Results showed that biomass burning, traffic‐related emissions, and coal combustion were the dominant contributors to eBC. The generalized additive model indicated that the reduction of traffic‐related eBC during the lockdown was entirely attributed to the decrease of emissions. Decreased biomass‐burning activities and favorable meteorological factors are both important drivers for the biomass‐burning eBC reduction during the lockdown. A radiative transfer model showed that the DRE efficiency of eBC from biomass burning was the strongest, followed by coal combustion and traffic‐related emissions. This study highlights that aggressive reduction in the consumption of residential solid fuels would be effective in achieving climate change mitigation.