TY - JOUR
T1 - In Situ Measurements of Molecular Markers Facilitate Understanding of Dynamic Sources of Atmospheric Organic Aerosols
AU - Lyu, Xiaopu
AU - Guo, Hai
AU - Yao, Dawen
AU - Lu, Haoxian
AU - Huo, Yunxi
AU - Xu, Wen
AU - Kreisberg, Nathan
AU - Goldstein, Allen H.
AU - Jayne, John
AU - Worsnop, Douglas
AU - Tan, Yan
AU - Lee, Shun Cheng
AU - Wang, Tao
N1 - Funding Information:
This study was supported by the Research Grants Council of the Hong Kong Special Administrative Region via Theme-Based Research Scheme (TRS) (Project T24-504/17-N), Collaborative Research Fund (CRF/C5004-15E), the Strategic Focus Area scheme of The Research Institute for Sustainable Urban Development at The Hong Kong Polytechnic University (1-BBW9) and General Research Fund (PolyU 152052/14E and PolyU 152052/16E) of Research Grants Council of Hong Kong Special Administrative Region. The authors would like to thank the HKEPD for providing the trace gases and meteorological data. X.L. acknowledges technical advice on TAG operation from Qiongqiong Wang and Xiao He in Hong Kong University of Science and Technology, and Yutong Liang in University of California, Berkeley.
Publisher Copyright:
Copyright © 2020 American Chemical Society
PY - 2020/9/15
Y1 - 2020/9/15
N2 - Reducing the amount of organic aerosol (OA) is crucial to mitigation of particulate pollution in China. We present time and air-origin dependent variations of OA markers and source contributions at a regionally urban background site in South China. The continental air contained primary OA markers indicative of source categories, such as levoglucosan, fatty acids, and oleic acid. Secondary OA (SOA) markers derived from isoprene and monoterpenes also exhibited higher concentrations in continental air, due to more emissions of their precursors from terrestrial ecosystems and facilitation of anthropogenic sulfate for monoterpenes SOA. The marine air and continental-marine mixed air had more abundant hydroxyl dicarboxylic acids (OHDCA), with anthropogenic unsaturated organics as potential precursors. However, OHDCA formation in continental air was likely attributable to both biogenic and anthropogenic precursors. The production efficiency of OHDCA was highest in marine air, related to the presence of sulfur dioxide and/or organic precursors in ship emissions. Regional biomass burning (BB) was identified as the largest contributor of OA in continental air, with contributions fluctuating from 8% to 74%. In contrast, anthropogenic SOA accounted for the highest fraction of OA in marine (37 ± 4%) and mixed air (31 ± 3%), overriding the contributions from BB. This study demonstrates the utility of molecular markers for discerning OA pollution sources in the offshore marine atmosphere, where continental and marine air pollutants interact and atmospheric oxidative capacity may be enhanced.
AB - Reducing the amount of organic aerosol (OA) is crucial to mitigation of particulate pollution in China. We present time and air-origin dependent variations of OA markers and source contributions at a regionally urban background site in South China. The continental air contained primary OA markers indicative of source categories, such as levoglucosan, fatty acids, and oleic acid. Secondary OA (SOA) markers derived from isoprene and monoterpenes also exhibited higher concentrations in continental air, due to more emissions of their precursors from terrestrial ecosystems and facilitation of anthropogenic sulfate for monoterpenes SOA. The marine air and continental-marine mixed air had more abundant hydroxyl dicarboxylic acids (OHDCA), with anthropogenic unsaturated organics as potential precursors. However, OHDCA formation in continental air was likely attributable to both biogenic and anthropogenic precursors. The production efficiency of OHDCA was highest in marine air, related to the presence of sulfur dioxide and/or organic precursors in ship emissions. Regional biomass burning (BB) was identified as the largest contributor of OA in continental air, with contributions fluctuating from 8% to 74%. In contrast, anthropogenic SOA accounted for the highest fraction of OA in marine (37 ± 4%) and mixed air (31 ± 3%), overriding the contributions from BB. This study demonstrates the utility of molecular markers for discerning OA pollution sources in the offshore marine atmosphere, where continental and marine air pollutants interact and atmospheric oxidative capacity may be enhanced.
UR - http://www.scopus.com/inward/record.url?scp=85091125614&partnerID=8YFLogxK
U2 - 10.1021/acs.est.0c02277
DO - 10.1021/acs.est.0c02277
M3 - Journal article
C2 - 32805105
AN - SCOPUS:85091125614
SN - 0013-936X
VL - 54
SP - 11058
EP - 11069
JO - Environmental Science and Technology
JF - Environmental Science and Technology
IS - 18
ER -