Impacts of COVID-19 Lockdown on Air Quality in Shenzhen in Spring 2022 深圳市 2022 年春季新冠疫情管控期间空气质量分析

Liu，Chan Fang1; Zhang，Ao Xing2; Fang，Qing1; Ye，Yu Jing1; Yang，Hong Long3; Chen，Jiong Kai2; Wu，Wen Lu2; Hou，Yue2; Mo，Jia Jia2; Fu，Tzung May2

2023-06-01

10.13227/j.hjkx.202205313

Huanjing Kexue/Environmental Science   Impact Factor & Quartile

0250-3301

The short-term reduction of air pollutant emissions is an important emergency control measure for avoiding air pollution exceedances in Chinese cities. However, the impacts of short-term emission reductions on the air qualities in southern Chinese cities in spring has not been fully explored. We analyzed the changes in air quality in Shenzhen, Guangdong before, during, and after a city-wide lockdown associated with COVID-19 control during March 14 to 20, 2022. Stable weather conditions prevailed before and during the lockdown, such that local air pollution was strongly affected by local emissions. In-situ measurements and WRF-GC simulations over the Pearl River Delta (PRD) both showed that, due to reductions in traffic emissions during the lockdown, the concentrations of nitrogen dioxide (NO ), respirable particulate matter (PM ), and fine particulate matters (PM ) in Shenzhen decreased by (- 26 ± 9. 5)%, (- 28 ± 6. 4)%, and (- 20 ± 8. 2)%, respectively. However, surface ozone (O ) concentration did not change significantly [(-1. 0 ±6. 5)%]. TROPOMI satellite observations of formaldehyde and nitrogen dioxide column concentrations indicated that the ozone photochemistry in the PRD in spring 2022 was mainly controlled by the volatile organic compound (VOCs) concentrations and was not sensitive to the reduction in nitrogen oxide (NO ) concentrations. Reduction in NO may even have increased O because the titration of O by NO was weakened. Due to the small spatial-temporal extent of emission reductions, the air quality effects caused by this short-term urban-scale lockdown were weaker than the air quality effects across China during the widespread COVID-19 lockdown in 2020. Future air quality management in South China cities should consider the impacts of NO emission reduction on ozone and focus on the co-reduction scenarios of NO and VOCs.

collaborative control COVID-19 lockdown ozone pollution SouthChina spring

Chinese

Others

2-s2.0-85162992874

Scopus

1.Shenzhen Ecological and Environmental Monitoring Center of Guangdong Province,Shenzhen,518049,China
2.School of Environmental Science and Engineering,Southern University of Science and Technology,Shenzhen,518055,China
3.Shenzhen National Climate Observatory,Shenzhen,518040,China

Liu，Chan Fang,Zhang，Ao Xing,Fang，Qing,等. Impacts of COVID-19 Lockdown on Air Quality in Shenzhen in Spring 2022 深圳市 2022 年春季新冠疫情管控期间空气质量分析[J]. Huanjing Kexue/Environmental Science,2023,44(6):3117-3129.

Liu，Chan Fang.,Zhang，Ao Xing.,Fang，Qing.,Ye，Yu Jing.,Yang，Hong Long.,...&Fu，Tzung May.(2023).Impacts of COVID-19 Lockdown on Air Quality in Shenzhen in Spring 2022 深圳市 2022 年春季新冠疫情管控期间空气质量分析.Huanjing Kexue/Environmental Science,44(6),3117-3129.

Liu，Chan Fang,et al."Impacts of COVID-19 Lockdown on Air Quality in Shenzhen in Spring 2022 深圳市 2022 年春季新冠疫情管控期间空气质量分析".Huanjing Kexue/Environmental Science 44.6(2023):3117-3129.