Enhanced aqueous-phase formation of secondary organic aerosols due to the regional biomass burning over North China Plain. (January 2020)

• Record Type: Journal Article
• Authors: Wang, Jiayuan; Wang, Gehui; Wu, Can; Li, Jianjun; Cao, Cong; Li, Jin; Xie, Yuning; Ge, Shuangshuang; Chen, Jianmin; Zeng, Limin; Zhu, Tong; Zhang, Renjian; Kawamura, Kimitaka
• Is Part Of: Environmental pollution. Volume 256(2020)
• Publication Date: 2020-01
• Subjects: Dicarboxylic acids -- Aging process -- Aerosol liquid water content -- Aqueous-phase formation -- Stable carbon isotopic composition; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2019.113401
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: This study reveals the impact of biomass burning (BB) on secondary organic aerosols (SOA) formation in the North China Plain (NCP). Filter samples were analyzed for secondary inorganic aerosols (SIA), oxalic acid (C2 ) and related aqueous-phase SOA compounds (aqSOA), stable carbon isotope composition of C2 (δ 13 C(C2 )) and aerosol liquid water content (ALWC). Based on the PM2.5 loadings, BB tracer concentrations, wildfire spots and air-mass back trajectories, we distinguished two episodes from the whole campaign, Episode I and Episode II, which were characteristic of regional and local BB, respectively. The abundances of PM2.5 and organic matter in the two events were comparable, but concentrations and fractions of SIA, aqSOA during Episode I were much higher than those during Episode II, along with heavier δ 13 C(C2 ), suggesting an enhanced aqSOA formation in the earlier period. We found that the enhancement of aqSOA formation during Episode I was caused by an increased ALWC, which was mainly driven by SIA during the regional BB event. Our work showed that intensive burning of crop residue in East Asia can sharply enhance aqSOA production on a large scale, which may have a significant impact on the regional climate and human health. Graphical abstract: Image 1 Highlights: Intensive regional biomass burning could lead to high aerosol liquid water content. Aqueous-phase secondary organic aerosols was enhanced by aerosol liquid water. Positive feedback loop between secondary inorganic, organic aerosols and aerosol water. Regional biomass burning had heavier oxalic acid stable isotopes than locally. Abstract : Our study shows that aqueous-phase SOA (aqSOA) were largely enhanced by the aerosol liquid water content (ALWC), which was mainly driven by secondary inorganic aerosols during the intensive regional biomass burning of the crop residues.