Source apportionment of marine atmospheric aerosols in northern South China Sea during summertime 2018

Baoling Liang; Mingfu Cai; Qibin Sun; Shengzhen Zhou; Jun Zhao

doi:10.1016/j.envpol.2021.117948

Source apportionment of marine atmospheric aerosols in northern South China Sea during summertime 2018

Environ Pollut. 2021 Nov 15:289:117948. doi: 10.1016/j.envpol.2021.117948. Epub 2021 Aug 11.

Authors

Baoling Liang¹, Mingfu Cai², Qibin Sun¹, Shengzhen Zhou³, Jun Zhao⁴

Affiliations

¹ School of Atmospheric Sciences, Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, and Institute of Earth Climate and Environment System, Sun Yat-sen University, Zhuhai, Guangdong, 519082, China.
² School of Atmospheric Sciences, Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, and Institute of Earth Climate and Environment System, Sun Yat-sen University, Zhuhai, Guangdong, 519082, China; Institute for Environmental and Climate Research, Jinan University, Guangzhou, Guangdong, 511443, China.
³ School of Atmospheric Sciences, Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, and Institute of Earth Climate and Environment System, Sun Yat-sen University, Zhuhai, Guangdong, 519082, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, Guangdong, 519082, China; Guangdong Provincial Observation and Research Station for Climate Environment and Air Quality Change in the Pearl River Estuary, Zhuhai, Guangdong, 519082, China; Key Laboratory of Tropical Atmosphere-Ocean System, Ministry of Education, Zhuhai, Guangdong, 519082, China.
⁴ School of Atmospheric Sciences, Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, and Institute of Earth Climate and Environment System, Sun Yat-sen University, Zhuhai, Guangdong, 519082, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, Guangdong, 519082, China; Guangdong Provincial Observation and Research Station for Climate Environment and Air Quality Change in the Pearl River Estuary, Zhuhai, Guangdong, 519082, China; Key Laboratory of Tropical Atmosphere-Ocean System, Ministry of Education, Zhuhai, Guangdong, 519082, China. Electronic address: zhaojun23@mail.sysu.edu.cn.

PMID: 34426195
DOI: 10.1016/j.envpol.2021.117948

Abstract

Marine atmospheric aerosols play important roles in the global radiation balance and climate change. Hence, measuring physiochemical aerosol properties is essential to better understand their formation, aging processes, and source origins. However, high temporal resolution measurements of submicron particles are currently scarce in the northern South China Sea (SCS). In this study, we conducted a ship-based cruise campaign with a scanning mobility particle sizer and an online time of flight aerosol chemical speciation monitor to measure the particle number size distribution (PNSD) and the chemical composition of submicron particles over the northern SCS during summer 2018. The mean concentration of non-refractory submicron particulate matter (NR-PM₁) was generally 9.11 ± 4.86 μg m^-3; sulfate was the most abundant component, followed by organics, ammonium, nitrate, and chloride. Positive matrix factorization (PMF) analysis was applied to the PNSD (size PMF) and organic aerosols (OA PMF) and further investigated the source apportionment of the submicron particles. The size PMF identified four factors, including ship exhaust, ship influencing marine primary, continent affected marine secondary, and mixed accumulation aerosols. The most abundant particles in the number concentration were associated with ship emissions, which accounted for approximately 44 %. The submicron organic aerosols were highly oxidized and composed of low-volatility oxygenated OA (LV-OOA, 68 %), semi-volatile OOA (SV-OOA, 21 %), and hydrocarbon-like OA (HOA, 11 %). The backward trajectory of air masses showed that the northern SCS was most frequently (64.7 %) influenced by air masses from the Indo-Chinese Peninsula (ICP) during the campaign, implying that pollutants from ICP have a significant impact on the atmosphere of the northern SCS during summer. Thus, in situ ship-based cruise measurements can provide valuable data on the physiochemical characteristics of marine atmospheric aerosols to better understand their source origins.

Keywords: Aerosol chemical speciation monitor; Chemical composition; Organic aerosols; Positive matrix factorization; Submicron particles.

MeSH terms

Aerosols / analysis
Air Pollutants* / analysis
China
Environmental Monitoring
Nitrates
Particulate Matter / analysis

Substances

Aerosols
Air Pollutants
Nitrates
Particulate Matter