Developing the Maximum Incremental Reactivity for Volatile Organic Compounds in Major Cities of Central‐Eastern China

Abstract

AbstractThe Chinese government has identified volatile organic compounds (VOCs) management as a key priority in the fourteenth Five‐Year Plan (2021–2025) to alleviate ground‐level ozone (O3) air pollution. To provide scientific support for VOCs management, we developed the localized maximum incremental reactivity (MIR) for 57 VOCs species (prescribed by the Photochemical Assessment Monitoring Stations (PAMS)) in eight representative cities and averaged urban conditions over Central‐Eastern China, with application of the Master Chemical Mechanism box model coupled with solid observational constraints. Though the exact environmental conditions differ among cities, all of them are in VOCs‐limited O3 formation regime, underlining the importance of VOCs to O3 formation. The MIRs constructed based on regional average scenarios are well representative of those constructed based on individual cities, with Guangzhou as an exception due to its vast variance in chemical environments. The localized MIRs displayed the same overall pattern as the U.S. MIRs, but differed largely with respect to a few species (especially alkenes), owing to a combined influence of many factors. We applied the localized MIRs to quantify the concentration‐weighted ozone formation potential (OFP), which elucidate the importance of aromatics to O3 formation in the Chinese metropolitan areas. The top 10 key VOC species together with their explicitly tracked emission sources were determined, which could offer references for the formulation of effective control policies. The localized MIRs developed in this study can be applied to quantify OFPs for VOCs in Chinese cities, which has a great significance to VOCs management and O3 pollution control.