Upward trend and formation of surface ozone in the Guanzhong Basin, Northwest China

Yonggang Xue; Liqin Wang; Suixin Liu; Yu Huang; Long Chen; Long Cui; Junji Cao

doi:10.1016/j.jhazmat.2021.128175

Upward trend and formation of surface ozone in the Guanzhong Basin, Northwest China

J Hazard Mater. 2022 Apr 5:427:128175. doi: 10.1016/j.jhazmat.2021.128175. Epub 2021 Dec 29.

Authors

Yonggang Xue¹, Liqin Wang¹, Suixin Liu¹, Yu Huang², Long Chen¹, Long Cui¹, Junji Cao¹

Affiliations

¹ State Key Lab of Loess and Quaternary Geology (SKLLQG), Institute of Earth Environment, Chinese Academy of Sciences (CAS), Xi'an 710061, China; CAS Center for Excellence in Quaternary Science and Global Change, Xi'an 710061, China; Guanzhong Plain Ecological Environment Change and Comprehensive Treatment National Observation and Research Station, Xi'an 710061, China.
² State Key Lab of Loess and Quaternary Geology (SKLLQG), Institute of Earth Environment, Chinese Academy of Sciences (CAS), Xi'an 710061, China; CAS Center for Excellence in Quaternary Science and Global Change, Xi'an 710061, China; Guanzhong Plain Ecological Environment Change and Comprehensive Treatment National Observation and Research Station, Xi'an 710061, China. Electronic address: huangyu@ieecas.cn.

PMID: 34995999
DOI: 10.1016/j.jhazmat.2021.128175

Abstract

Increase trend of surface ozone (O₃) was observed in the Guanzhong Basin (GZB) from 2014 to 2020 with growth rates of 3.9-6.4 μg m^-3 yr^-1 for the maximum daily average 8 h (MDA8) O₃ concentrations. To further understand the formation of O₃, investigation of volatile organic compounds (VOCs) was carried out in the summer of 2018. High levels of VOCs were observed in both residential area and industrialized cities. Elevated concentrations of none-methane Hydrocarbon (NMHCs) were observed in rush hours, which indicated dominated roles of traffic activities on the loading of ambient VOCs. In the nighttime, both of NMHCs and oxygenated VOCs (OVOCs) were raised, and the peaks of VOCs kept pace with accumulation of O₃. Wind field indicated that northward and westward air mass, which passed through the remote forest and industrial area in east of the GZB, was responsible to elevated ambient VOCs in the GZB. Traffic emission, fuel evaporation, and solvent using were key contributors to ambient NMHCs, while solvent using and secondary formation dominated the loading of OVOCs. The present study indicated that both local management and regional collaborative control on active VOCs species from typical sources is urgently needed in GZB.

Keywords: Ozone; Regional transport; Traffic exhaust; VOCs.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Air Pollutants* / analysis
China
Environmental Monitoring
Ozone* / analysis
Volatile Organic Compounds* / analysis

Substances

Air Pollutants
Volatile Organic Compounds
Ozone