| Title: | "Diagnostic analysis of regional ozone pollution in Yangtze River Delta, China: A case study in summer 2020" |
| Author(s): | Li L; Xie F; Li J; Gong K; Xie X; Qin Y; Qin M; Hu J; |
| Address: | "Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Nanjing University of Information Science & Technology, Nanjing 210044, China. Nanjing Municipal Academy of Ecological and Environment Protection Science, Nanjing 210093, China. Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Nanjing University of Information Science & Technology, Nanjing 210044, China. Electronic address: jianlinhu@nuist.edu.cn" |
| DOI: | 10.1016/j.scitotenv.2021.151511 |
| ISSN/ISBN: | 1879-1026 (Electronic) 0048-9697 (Linking) |
| Abstract: | "A regional ozone (O(3)) pollution event occurred in the Yangtze River Delta region during August 17-23, 2020 (except on August 21). This study aims to understand the causes of O(3) pollution during the event using an emission-based model (i.e., the Community Multiscale Air Quality (CMAQ) model) and an observation-based model (OBM). The OBM was used to investigate O(3) sensitivity to its precursors during the O(3) pollution, concluding that O(3) formation was limited by volatile organic compounds (VOCs) on August 19, but was co-limited by VOCs and nitrogen oxides (NOx) on other polluted days. Aromatics and alkenes were the two main VOC groups contributing to the O(3) formation, with trans-2-butene and m/p-xylene as the key species among the VOCs measured at the Nanjing urban site. The source apportionment results estimated using the source-oriented CMAQ model suggest that the transportation and industry sources dominated the non-background O(3) production in Nanjing, which were responsible for 52% and 24.7%, respectively. The O(3) concentration attributed to NOx (~70%) was significantly higher than that attributed to VOCs (approximately 30%). The process analysis revealed that vertical mixing increased the O(3) concentrations in the early morning, and photochemical reactions promoted O(3) formation and accumulation during the daytime within the planetary boundary layer. At night, outflow from horizontal transport and nocturnal chemistry jointly resulted the O(3) depletion. The contributions of inter-city transport during the O(3) pollution period in Nanjing were also estimated. The predicted O(3) concentration was largely recorded from long-distance regions, reaching 46%, followed by local sources (38%) and surrounding cities (16%). The results indicate that both NOx and VOCs contributed significantly to O(3) pollution during this event, and the emissions controls of NOx and the key VOC species of aromatics and alkenes from a cooperative regional perspective should be considered to mitigate O(3) pollution" |
| Keywords: | *Air Pollutants/analysis China Environmental Monitoring *Ozone/analysis *Volatile Organic Compounds/analysis Ozone Process analysis Regional transport Relative incremental reactivity Source apportionment; |
| Notes: | "MedlineLi, Lin Xie, Fangjian Li, Jingyi Gong, Kangjia Xie, Xiaodong Qin, Yang Qin, Momei Hu, Jianlin eng Netherlands 2021/11/12 Sci Total Environ. 2022 Mar 15; 812:151511. doi: 10.1016/j.scitotenv.2021.151511. Epub 2021 Nov 8" |
