“…The uncertainties (i.e., 95% confidence intervals around the central estimates) of Chinese emissions of SO 2 , NO x , total PM, PM 10 , PM 2.5 , black carbon (BC), and organic carbon (OC) were estimated to be −14%~13%, −13%~37%, −11%~38%, −14%~45%, −17%~54%, −25%~136%, and −40%~121%, respectively [22]. The average uncertainties of emissions from the JJJ region were estimated through the Monte Carlo method as −18% to 16% for SO 2 , −17% to 15% for NO x , −24% to 23% for PM 2.5 , −19% to 18% for PM 10 , −25% to 23% for CO, −48% to 44% for NMVOC, −54% to 48% for NH 3 , −54% to 49% for BC, and −59% to 55% for OC, which was compiled using a bottom-up approach based on detailed data of major air pollution sources [23]. In total, the model predictions of PM 2.5 generally agree with ambient measured values, but the model performance varies in different regions.Since the enforcement of the Air Pollution Prevention and Control Action Plan posted by the State Council in 2013, winter PM 2.5 pollution in China has decreased over the period 2013-2016 in response to reduced coal consumption and pollution prevention efforts.…”