PMID- 37309931
OWN - NLM
STAT- MEDLINE
DCOM- 20230614
LR  - 20230614
IS  - 0250-3301 (Print)
IS  - 0250-3301 (Linking)
VI  - 44
IP  - 6
DP  - 2023 Jun 8
TI  - [Impacts of COVID-19 Lockdown on Air Quality in Shenzhen in Spring 2022].
PG  - 3117-3129
LID - 10.13227/j.hjkx.202205313 [doi]
AB  - 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(2)), respirable particulate matter 
      (PM(10)), and fine particulate matters (PM(2.5)) in Shenzhen decreased by 
      (-26+/-9.5)%, (-28+/-6.4)%, and (-20+/-8.2)%, respectively. However, surface ozone 
      (O(3)) 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(x)) concentrations. Reduction in NO(x) may even 
      have increased O(3,) because the titration of O(3) by NO(x) 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(x) 
      emission reduction on ozone and focus on the co-reduction scenarios of NO(x) and 
      VOCs.
FAU - Liu, Chan-Fang
AU  - Liu CF
AD  - Shenzhen Ecological and Environmental Monitoring Center of Guangdong Province, 
      Shenzhen 518049, China.
FAU - Zhang, Ao-Xing
AU  - Zhang AX
AD  - School of Environmental Science and Engineering, Southern University of Science 
      and Technology, Shenzhen 518055, China.
FAU - Fang, Qing
AU  - Fang Q
AD  - Shenzhen Ecological and Environmental Monitoring Center of Guangdong Province, 
      Shenzhen 518049, China.
FAU - Ye, Yu-Jing
AU  - Ye YJ
AD  - Shenzhen Ecological and Environmental Monitoring Center of Guangdong Province, 
      Shenzhen 518049, China.
FAU - Yang, Hong-Long
AU  - Yang HL
AD  - Shenzhen National Climate Observatory, Shenzhen 518040, China.
FAU - Chen, Jiong-Kai
AU  - Chen JK
AD  - School of Environmental Science and Engineering, Southern University of Science 
      and Technology, Shenzhen 518055, China.
FAU - Wu, Wen-Lu
AU  - Wu WL
AD  - School of Environmental Science and Engineering, Southern University of Science 
      and Technology, Shenzhen 518055, China.
FAU - Hou, Yue
AU  - Hou Y
AD  - School of Environmental Science and Engineering, Southern University of Science 
      and Technology, Shenzhen 518055, China.
FAU - Mo, Jia-Jia
AU  - Mo JJ
AD  - School of Environmental Science and Engineering, Southern University of Science 
      and Technology, Shenzhen 518055, China.
FAU - Fu, Tzung-May
AU  - Fu TM
AD  - School of Environmental Science and Engineering, Southern University of Science 
      and Technology, Shenzhen 518055, China.
LA  - chi
PT  - English Abstract
PT  - Journal Article
PL  - China
TA  - Huan Jing Ke Xue
JT  - Huan jing ke xue= Huanjing kexue
JID - 8405344
RN  - 0 (Air Pollutants)
RN  - S7G510RUBH (Nitrogen Dioxide)
RN  - 66H7ZZK23N (Ozone)
RN  - 31C4KY9ESH (Nitric Oxide)
RN  - 0 (Particulate Matter)
RN  - 0 (Volatile Organic Compounds)
SB  - IM
MH  - Humans
MH  - *Air Pollutants
MH  - Nitrogen Dioxide
MH  - *COVID-19
MH  - Communicable Disease Control
MH  - *Air Pollution
MH  - *Ozone
MH  - Nitric Oxide
MH  - Particulate Matter
MH  - *Volatile Organic Compounds
OTO - NOTNLM
OT  - COVID-19 lockdown
OT  - SouthChina
OT  - collaborative control
OT  - ozone pollution
OT  - spring
EDAT- 2023/06/13 13:12
MHDA- 2023/06/14 06:42
CRDT- 2023/06/13 07:33
PHST- 2023/06/14 06:42 [medline]
PHST- 2023/06/13 13:12 [pubmed]
PHST- 2023/06/13 07:33 [entrez]
AID - 10.13227/j.hjkx.202205313 [doi]
PST - ppublish
SO  - Huan Jing Ke Xue. 2023 Jun 8;44(6):3117-3129. doi: 10.13227/j.hjkx.202205313.