What caused ozone pollution during the 2022 Shanghai lockdown? Insights from ground and satellite observations

Abstract 3) concentrations to emission reductions in a high-O3 season. In this study, we analysed surface observations of O3 and nitrogen dioxide (NO2) concentrations and satellite-retrieved tropospheric NO2 and formaldehyde (HCHO) column concentrations in the first 5 months of 2022 with comparisons to the year 2021. During the 2-month 2022 lockdown, the maximum daily 8 h average (MDA8) O3 concentrations at 1 or more of the city's 19 sites exceeded China's air quality standard of 160 µ g m - 3 21 times, with the highest value being 200 µ g m - 3. The city-average MDA8 O3 concentration increased by 13 % in April–May 2022 year-on-year, despite sharp declines in NO2 surface and column concentrations (both by 49 %) and a 19 % decrease in the HCHO column concentration. These results show that the reductions in O3 precursors and other pollutants during the 2022 lockdown did not prevent ground-level O3 pollution. An analysis of meteorological data indicates that there were only small changes in the meteorological conditions, and there was little transport of O3 from the high-O3 inland regions during the 2022 lockdown, neither of which can account for the increased and high concentrations of O3 that were observed during this period. The mean HCHO/NO 2 3 and NO2 concentrations changed from negative in 2021 to positive in 2022. These results indicate that the high O3 concentrations in 2022 were mainly due to large reductions in the emissions of NO x ∼ 60  %), whereas its semi-rural areas transitioned from VOC-limited to VOC–NO x 3 pollution in urban areas of Shanghai and possibly other VOC-limited metropoles without the imposition of additional VOC controls or more substantial decreases in NO x emissions.

Object Details

• Location: Deutsche Nationalbibliothek Frankfurt am Main
• Extent: Online-Ressource
• Language: Englisch

References and Relationships

• Bibliographic citation: What caused ozone pollution during the 2022 Shanghai lockdown? Insights from ground and satellite observations ; volume:22 ; number:22 ; year:2022 ; pages:14455-14466 ; extent:12 ; Atmospheric chemistry and physics ; 22, Heft 22 (2022), 14455-14466 (gesamt 12)

Contributors, Places and Time

• Creator: Tan, Yue ; Wang, Tao

Further information

• DOI: 10.5194/acp-22-14455-2022
• URN: urn:nbn:de:101:1-2022111704283038047588
• Rights: Open Access; Der Zugriff auf das Objekt ist unbeschränkt möglich.
• Last update: 15.08.2025, 7:29 AM CEST