Efficacy of China's clean air actions to tackle PM2.5 pollution between 2013 and 2020

Beginning in 2013, China launched two phases (2013–2017 and 2017–2020) of clean air actions that have led to substantial reductions in PM2.5 concentrations. However, improvement in PM2.5 pollution was notably slowing down during Phase II. Here, we quantified the efficacy and drivers of PM2.5 improvement and evaluated the associated cost during 2013–2020 using an integrated framework that combines an emission inventory model, a chemical transport model, and detailed cost information.