资源环境科技发展态势分析平台

Persistent 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 ppbv 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.