The variations of VOCs based on the policy change of Omicron in polluted winter in traffic-hub city, China

• DOI: 10.5194/egusphere-2024-575
• Publication Date: 2024-03-08T07:22:50Z
• Authors: Bowen Zhang; Dong Zhang; Zhe Dong; Xinshuai Song; Ruiqin Zhang; Xiao Li

Abstract. Online volatile organic compounds (VOCs) were continuous monitored before and after the Omicron policy change at an urban site in polluted Zhengzhou from December 1, 2022, to January 31, 2023. The characteristics sources of VOCs explored. daily average concentration PM2.5 total (TVOCs) ranged 54 239 µg/m3 15.6 57.1 ppbv with value 112 ± 45 36.1 21.0 ppbv, respectively during entire period. values TVOCs Case 3 (pollution episode abolishment “Nucleic Acid Screening Measures for all staff” policy) 1.3 1.8 times 1 policy). 48.4 20.4 67.6 19.6 respectively, increased by 63 % 188 compared clean days. Alkanes found be most abundant Equivalent volume contribution halogenated hydrocarbon oxygenated (15 %) 3, followed alkenes (10 %). Though contributions aromatics lowest (6 7 3), highest increasing ratio was days episodes. Positive Matrix Factor model results showed that main source observation period industrial emissions, which accounted 30 TVOCs, vehicular emission (24 combustion (23 became largest (40 (29 %), consisting large numbers people going out blockade. Secondary aerosol formation potential (SOAFP) 37 109 µg/m3, SOAFP (17–19 μg/m3 31–51 both 3. Solvent usage had second (9 16 μg/m3) 23 31 respectively. control emission, solvent should focused Zhengzhou, also important pollution winter.