| Title: | Parameterized atmospheric oxidation capacity and speciated OH reactivity over a suburban site in the North China Plain: A comparative study between summer and winter |
| Author(s): | Yang Y; Wang Y; Huang W; Yao D; Zhao S; Wang Y; Ji D; Zhang R; Wang Y; |
| Address: | "Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China; University of the Chinese Academy of Sciences, Beijing 100049, China. Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China; Institute for Atmospheric and Earth System Research, Physics, Faculty of Science, P.O. Box 64, 00014, University of Helsinki, Helsinki, Finland. Electronic address: yonghong.wang@helsinki.fi. Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China; University of the Chinese Academy of Sciences, Beijing 100049, China; Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China. Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China. Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China; University of the Chinese Academy of Sciences, Beijing 100049, China; Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China. Electronic address: wys@mail.iap.ac.cn" |
| DOI: | 10.1016/j.scitotenv.2021.145264 |
| ISSN/ISBN: | 1879-1026 (Electronic) 0048-9697 (Linking) |
| Abstract: | "The atmospheric oxidation capacity (AOC) and photochemical reactivity are of increasing concern owing to their roles in photochemical pollution. The AOC and OH reactivity were evaluated based on simultaneous measurements of volatile organic compounds (VOCs), trace gases and photolysis frequency during summer and winter campaigns at a suburban site in Xianghe. The AOC exhibited well-defined seasonal and diurnal patterns, with higher intensities during the summertime and daytime than during the wintertime and nighttime, respectively. The major reductants contributing to the AOC during the summertime were CO (41%) and alkenes (41%), whereas CO (40%) and oxygenated VOCs (OVOCs) (30%) dominated the AOC during the wintertime. The dominant oxidant contributor to the AOC during the daytime was OH (>/=93%), while the contributions of O(3) and NO(3) (>/=75%) to the AOC increased during the nighttime. High values during the wintertime and an increase at night were features of the speciated OH reactivity. Inorganic compounds (NO(x) and CO) dominated the speciated OH reactivity (76% and 85% during the summer and winter campaigns, respectively). Among VOCs, the dominant contributors were alkenes (12%) and OVOCs (7%) during the summer and winter campaigns, respectively. The ratio of NO(x)- and VOC-attributed OH reactivity indicated that O(3) formation occurred under a VOC-limited regime during the summertime and that aromatics had the largest potential to form O(3.) Isoprene and m/p-xylene were the most important contributors to the AOC, OH reactivity and O(3)-forming among VOCs during the summertime, biogenic sources and secondary formation and industrial production were the main sources of these species. During the wintertime, hexanal and ethylene were the key VOC species contributing to the AOC and OH reactivity, and solvent usage and traffic-related emissions were the main contributing sources. We recommend that priority measures for the control of VOC species and sources should be taken when suitable. CAPSULE: This study focused on the similarities and differences in the AOC and speciated OH reactivity during summer and winter campaigns" |
| Keywords: | Aoc North China Plain Photochemical pollution Sources Speciated OH reactivity VOCs; |
| Notes: | "PubMed-not-MEDLINEYang, Yuan Wang, Yonghong Huang, Wei Yao, Dan Zhao, Shuman Wang, Yinghong Ji, Dongsheng Zhang, Renjian Wang, Yuesi eng Netherlands 2021/05/05 Sci Total Environ. 2021 Jun 15; 773:145264. doi: 10.1016/j.scitotenv.2021.145264. Epub 2021 Jan 23" |
