Effects of significant emission changes on PM2.5 chemical composition and optical properties from 2019 to 2021 in a typical industrial city of eastern China

Huang，Xiangpeng1,2,3; Li，Changping4; Pan，Chao5; Li，Yue'e4; Zheng，Wei3; Lin，Guangwu1; Li，Haiwei2; Zhang，Yunjiang2; Wang，Junfeng2; Lei，Yali6; Ye，Jianhuai3; Ge，Xinlei2,7; Zhang，Hongliang1,8,9

2024-05-01

10.1016/j.atmosres.2024.107287

Atmospheric Research   影响因子和分区

0169-8095

Restrictions on emission controls were implemented in China to cope with the outbreak of the Coronavirus Disease 2019 (COVID-19), providing a chance to study the impacts of anthropogenic emissions on air quality. Subsequently, three-year measurements of PM chemical composition and light absorption were conducted in a typical megacity (Suzhou) of the Yangtze River Delta in China from 2019 to 2021. The annual observation period was divided into four different stages: Normal Days, Chinese New Year, Lockdown, and Work Resumption. Our results show that the concentrations of PM composition (e.g., SO, NO, OC, and EC) and gas species (e.g., SO, NO, and CO) gradually decreased from 2019 to 2021, associated with emission reduction. During the four stages, the COVID-19 lockdown period had the lowest concentrations of PM, indicating that strict emission control could significantly improve the air quality. The significant increase in O during the COVID-19 lockdown period is likely due to the reduced NO emission from the traffic. The Normal Days in 2020 had the highest mass loadings of SO, NO, NH, OC, and EC, while the mass concentrations of SO, NO, NH, Cl, and Na in the Lockdown were the lowest. Meanwhile, aerosol light absorption has decreased yearly, and significant decreases in light absorption were observed during the COVID-19 lockdown. The high values of Absorption Ångström exponent (AAE) observed in Suzhou (ranging from 1.3 to 1.4), indicated that brown carbon played critical contributions to the light absorption. The mass concentration and fraction of fuel fossil were significantly higher than that of biomass burning during the entire campaign. The remarkable decline of fuel fossil BC during the COVID-19 lockdown can be attributed to the closure of factories and the reduction of vehicle emissions. The potential contribution source function analysis suggests a notable regional variation in the sources of fossil fuel and biomass combustion. Our results highlight that strict emission control could provide a positive direction for air pollution mitigation campaigns.

Chemical composition COVID-19 Optical properties Source apportionment Yangtze River Delta

SCI ; EI

英语

其他

GEOSCIENCES

2-s2.0-85185195079

Scopus

1.Department of Environmental Science and Engineering,Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention,Fudan University,Shanghai,200438,China
2.Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control,Collaborative Innovation Center of Atmospheric Environment and Equipment Technology,School of Environmental Science and Engineering,Nanjing University of Information Science and Technology,Nanjing,210044,China
3.School of Environmental Science and Engineering,Southern University of Science and Technology,Shenzhen,518055,China
4.Suzhou Environmental Monitoring Center,Suzhou,215011,China
5.China Energy Science and Technology Research Institute Co. Ltd.,Nanjing,210023,China
6.Key Lab of Geographic Information Science of the Ministry of Education,School of Geographic Sciences,East China Normal University,Shanghai,200241,China
7.School of Environment and Energy Engineering,Anhui Jianzhu University,Hefei,230601,China
8.Institute of Eco-Chongming (IEC),Shanghai,200062,China
9.IRDR ICoE on Risk Interconnectivity and Governance on Weather/Climate Extremes Impact and Public Health,Fudan University,Shanghai,200241,China

Huang，Xiangpeng,Li，Changping,Pan，Chao,et al. Effects of significant emission changes on PM2.5 chemical composition and optical properties from 2019 to 2021 in a typical industrial city of eastern China[J]. Atmospheric Research,2024,301.

Huang，Xiangpeng.,Li，Changping.,Pan，Chao.,Li，Yue'e.,Zheng，Wei.,...&Zhang，Hongliang.(2024).Effects of significant emission changes on PM2.5 chemical composition and optical properties from 2019 to 2021 in a typical industrial city of eastern China.Atmospheric Research,301.

Huang，Xiangpeng,et al."Effects of significant emission changes on PM2.5 chemical composition and optical properties from 2019 to 2021 in a typical industrial city of eastern China".Atmospheric Research 301(2024).