Impacts of post-harvest open biomass burning and evaluation of burning ban policy on a severe regional haze event in Northeast China

Abstract Open filed biomass burning is a major contributor to airborne particulate matter and reactive trace gases during the post-harvest season in Northeast China. Due to prevailing weather conditions and high emission density, this region is prone to the accumulation of air pollutants that lead to severe haze events. In this study, we integrated satellite products, monitoring data and a regional air quality modeling system to quantify the contribution of open biomass burning to total PM2.5 concentrations during an extreme episode. Results show that average PM2.5 (particulate matter with diameter less than 2.5 μm) concentrations in Heilongjiang, Jilin and Liaoning provinces during November 1–4 were 116.98 μg/m3, 98.60 μg/m3 and 70.17 μg/m3, respectively. Open biomass burning contributed 52.7% of PM2.5 concentrations during November 1–4 over Northeast China. The PM2.5 concentration would decrease by 48.1% in Northeast China with the same period fire emissions in 2018 following the implementation of government controls. This study could improve our understanding of the contribution of open biomass burning to regional haze, thereby assisting with policy making during post-harvest season.