Local and transboundary impacts of PM 2.5 sources identified in Seoul during the early stage of the COVID-19 outbreak

Atmospheric Pollution Research

article

Youngkwon Kim¹  Kwonho Jeon³  Jieun Park⁴  Kyuseok Shim⁵  Sang-Woo Kim⁵  Hye-Jung Shin⁶  Seung-Muk Yi¹  Philip K. Hopke⁷ 

[1] Department of Environmental Health Sciences, Graduate School of Public Health, Seoul National University;Division of Policy Research, Green Technology Center;Climate and Air Quality Research Department Global Environment Research Division, National Institute of Environmental Research, Incheon;Institute of Health and Environment, Seoul National University;School of Earth and Environmental Sciences, Seoul National University;Air Quality Research Division, National Institute of Environmental Research, Incheon;Center for Air Resources Engineering and Science, Clarkson University;Department of Public Health Sciences, University of Rochester, School of Medicine and Dentistry

关键词: PM 2.5;    COVID-19;    Source apportionment;    Dispersion normalized PMF;    Transboundary pollution;   

DOI  :  10.1016/j.apr.2022.101510

学科分类：农业科学（综合）

来源: Dokuz Eylul Universitesi * Department of Environmental Engineering

【 摘 要 】

Countries in Northeast Asia have been regulating PM 2.5 sources and studying their local and transboundary origins since PM 2.5 causes severe impacts on public health and economic losses. However, the separation of local and transboundary impacts is not fully realized because it is impossible to change air pollutant emissions from multiple countries experimentally. Exceptionally, the early stage of the COVID-19 outbreak (January–March 2020) provided a cross-country experiment to separate each impact of PM 2.5 sources identified in Seoul, a downwind area of China. We evaluated the contributions of PM 2.5 sources compared to 2019 using dispersion normalized positive matrix factorization (DN-PMF) during three meteorological episodes. Episodes 1 and 2 revealed transboundary impacts and were related to reduced anthropogenic emissions and accumulated primary pollutants in Northeast China. Anthropogenic emissions, except for the residential sector, decreased, but primary air pollutants accumulated by residential coal combustion enhanced secondary aerosol formation. Thus, the contributions of sulfate and secondary nitrate increased in Seoul during episode 1 but then decreased maximally with other primary sources (biomass burning, district heating and incineration, industrial sources, and oil combustion) during episode 2 under meteorological conditions favorable to long-range transport. Local impact was demonstrated by atmospheric stagnation during episode 3. Meteorological condition unfavorable to local dispersion elevated the contributions of mobile and coal combustion and further contributed to PM 2.5 high concentration events (HCE). Our study separates the local and transboundary impacts and highlights that cooperations in Northeast Asia on secondary aerosol formation and management of local sources are necessary.

【 授权许可】

CC BY