Asian dust storm performing the role in surface ozone reduction

Natural dust storms significantly contribute to air pollution by elevating atmospheric particle levels. These dust storms also influence atmospheric photochemical processes through surface reactions on dust particles. In this study, we conduct a quantitative analysis of the impact of dust aerosols on near ground ozone in China, integrating multiple observations with advanced modeling techniques. Our findings reveal a notable reduction in regional average ozone concentrations (1.8 – 12.0 ppbv) in 12 dust storm events during 2016 to 2023, compared to scenarios with minimal or no dust influence. The critical drivers of the ozone decline include interactions between dust aerosols and ozone, the relevant radicals and radiation, as well as adverse meteorological conditions. Among these factors, dust aerosols are estimated to account for 24±13% of the observed ozone reduction. Furthermore, heterogeneous removal pathways, such as the direct uptake of ozone and the adsorption of dinitrogen pentoxide (N₂O₅) and hydroperoxyl radicals (HO₂) by dust aerosols, are identified as the crucial mechanisms contributing to ozone depletion. These findings underscore the complex chemistry of dust-mediated processes, which profoundly influence tropospheric photochemical cycles and amplify ozone sensitivity in volatile organic compound (VOC)-limited atmospheric environments.