气候变化领域集成服务门户(CCPortal): Aerosol pH and chemical regimes of sulfate formation in aerosol water during winter haze in the North China Plain

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DOI	10.5194/acp-20-11729-2020
	Aerosol pH and chemical regimes of sulfate formation in aerosol water during winter haze in the North China Plain
	Tao W.; Su H.; Zheng G.; Wang J.; Wei C.; Liu L.; Ma N.; Li M.; Zhang Q.; Pöschl U.; Cheng Y.
发表日期	2020
ISSN	1680-7316
起始页码	11729
结束页码	11746
卷号	20 期号:20
英文摘要	Understanding the mechanism of haze formation is crucial for the development of deliberate pollution control strategies. Multiphase chemical reactions in aerosol water have been suggested as an important source of particulate sulfate during severe haze (Cheng et al., 2016; Wang et al., 2016). While the key role of aerosol water has been commonly accepted, the relative importance of different oxidation pathways in the aqueous phase is still under debate mainly due to questions about aerosol pH. To investigate the spatiotemporal variability of aerosol pH and sulfate formation during winter in the North China Plain (NCP), we have developed a new aerosol water chemistry (AWAC) module for the WRF-Chem model (Weather Research and Forecasting model coupled with Chemistry). Using the WRF-Chem- AWAC model, we performed a comprehensive survey of the atmospheric conditions characteristic for wintertime in the NCP focusing on January 2013. We find that aerosol pH exhibited a strong vertical gradient and distinct diurnal cycle which was closely associated with the spatiotemporal variation in the abundance of acidic and alkaline fine particle components and their gaseous counterparts. Over Beijing, the average aerosol pH at the surface layer was -5:4 and remained nearly constant around -5 up to -2 km above ground level; further aloft, the acidity rapidly increased to pH -0 at -3 km. The pattern of aerosol acidity increasing with altitude persisted over the NCP, while the specific levels and gradients of pH varied between different regions. In the region north of -41-N, the mean pH values at the surface level were typically greater than 6, and the main pathway of sulfate formation in aerosol water was S(IV) oxidation by ozone. South of -41-N, the mean pH values at the surface level were typically in the range of 4.4 to 5.7, and different chemical regimes and reaction pathways of sulfate formation prevailed in four different regions depending on reactant concentrations and atmospheric conditions. The NO2 reaction pathway prevailed in the megacity region of Beijing and the large area of Hebei Province to the south and west of Beijing, as well as part of Shandong Province. The transition metal ion (TMI) pathway dominated in the inland region to the west and the coastal regions to the east of Beijing, and the H2O2 pathway dominated in the region extending further south (Shandong and Henan provinces). In all of these regions, the O3 and TMI pathways in aerosol water, as well as the gas-particle partitioning of H2SO4 vapor, became more important with increasing altitude. Sensitivity tests show that the rapid production of sulfate in the NCP can be maintained over a wide range of aerosol acidity (e.g., pH D 4:2-5.7) with transitions from dominant TMI pathway regimes to dominant NO2=O3 pathway regimes. © 2020 EDP Sciences. All rights reserved.
语种	英语
scopus关键词	aerosol; atmospheric chemistry; atmospheric pollution; chemical reaction; haze; oxidation; ozone; pH; spatiotemporal analysis; sulfate; winter; Beijing [China]; China; Hebei; North China Plain
来源期刊	ATMOSPHERIC CHEMISTRY AND PHYSICS
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/247473
作者单位	Multiphase Chemistry Department, Max Planck Institute for Chemistry, Mainz, 55128, Germany; Minerva Research Group, Max Planck Institute for Chemistry, Mainz, 55128, Germany; Institute for Environmental and Climate Research, Jinan University, Guangzhou, 511443, China; Department of Earth System Science, Tsinghua University, Beijing, 100084, China
推荐引用方式 GB/T 7714	Tao W.,Su H.,Zheng G.,et al. Aerosol pH and chemical regimes of sulfate formation in aerosol water during winter haze in the North China Plain[J],2020,20(20).
APA	Tao W..,Su H..,Zheng G..,Wang J..,Wei C..,...&Cheng Y..(2020).Aerosol pH and chemical regimes of sulfate formation in aerosol water during winter haze in the North China Plain.ATMOSPHERIC CHEMISTRY AND PHYSICS,20(20).
MLA	Tao W.,et al."Aerosol pH and chemical regimes of sulfate formation in aerosol water during winter haze in the North China Plain".ATMOSPHERIC CHEMISTRY AND PHYSICS 20.20(2020).