Impacts of Ozone‐Vegetation Interactions on Ozone Pollution Episodes in North China and the Yangtze River Delta

Abstract

AbstractPersistent ozone (O3) pollution episodes (OPEs, with regionally averaged maximum daily 8‐h average (MDA8) O3 concentration exceeding 80 ppbv and lasting for 5 days or longer) occurred frequently in megalopolis over eastern China in recent years. Here, we apply a newly developed chemistry‐biosphere model (GEOS‐Chem‐YIBs) to comprehensively quantify the vegetation contributions to OPEs in North China and Yangtze River Delta (YRD) over May to October in 2014–2017. The simulated MDA8 O3 concentrations increases 16.7 and 16.6 ppbv) during OPEs in North China and YRD, of which about 1.4 ppbv (8.4%) and 3.8 ppbv (22.9%) are caused by the processes including increased BVOC emissions and reduced stomatal dry deposition. Furthermore, the O3 damages to vegetation stomata slightly increase seasonal‐mean O3 concentrations by <1 ppbv, but such effects are not exacerbated during OPEs despite the high O3 exposure.