Unraveling the complexities of ozone and PM2.5 pollution in the Pearl River Delta region: Impacts of precursors emissions and meteorological factors, and effective mitigation strategies

Abstract

Ozone (O₃) and fine particulate matter (PM_2.5) are known to be interconnected due to shared precursor compounds. While numerous studies have examined the impact of precursors and meteorological factors on compound pollution events, few have proposed effective mitigation strategies tailored to specific regions. In this study, we conducted simulations of two types of O₃ and PM_2.5 pollution events in the Pearl River Delta (PRD) region during 2018 using the GEOS-Chem model. We applied a multiple linear regression model to quantify and distinguish the contributions of precursor emissions and meteorological factors to these events. Our findings highlight the predominant role of precursor emission factors in driving these pollution events. Notably, reducing NO_x emissions in the Pearl River Estuary (PRE) region was found to exacerbate O₃ pollution during specific periods, while reducing emissions of C4 alkanes (ALK4), lumped C3 alkenes (PRPE) and NH₃ in proportion to their respective contributions emerged as an effective strategy to mitigate combined O₃ and PM_2.5 pollution. This research elucidates the mechanisms underlying O₃ and PM_2.5 compound pollution in the PRD region and presents a practical and significant approach to managing air pollution in this area.