Journal article
Influence of relative humidity on aerosol composition: Impacts on light extinction and visibility impairment at two sites in coastal area of China
Atmospheric research, Vol.153, pp.500-511
02/2015
DOI: 10.1016/j.atmosres.2014.10.009
Abstract
Investigation on the aerosol characteristics, surface visibility (Vis) and meteorology at BGS (Baguanshan, Qingdao) and LNA (Lin'an, Zhejiang) shows that the ambient aerosol chemical composition and light extinction are relative humidity (RH) dependent. At higher RH, both the strengthened hygroscopic growth and the more efficient oxidization (of the precursor gases and formation of the secondary sulfate and nitrate) contribute to the increase of the mass fraction of the hygroscopic species, which consequently results in the increase of the aerosol mass extinction efficiency (MEE) and Vis reduction at the two Chinese coastal sites. MEE and chemical composition of the aerosol vary significantly under different regional transport ways; the airmasses from the ocean directions are associated with higher RH, higher sulfate mass fraction and greater MEE at BGS, while MEEs are smaller and associated with lower RH and lower sulfate fraction for the airmasses from the continent directions. Vis shows better correlation with PM2.5 and PM10 mass concentrations when RH effect on aerosol hygroscopic growth is considered. At BGS, the sulfate mass fraction in PM2.5 and PM10 (in average 32.4% and 27.4%) can explain about 60.7% and 74.3% of the variance of the aerosol MEE, respectively; sulfate and nitrate contribute to about 61% of the light extinction. RH plays a key role in aerosol extinction and visibility variation over this coastal area of China. Formation of the secondary aerosol (especially sulfate and nitrate) as well as hygroscopic growth under favorable (more stable and humid) meteorological conditions should be paid adequate attention in regulation of air quality and Vis improvement over eastern China in addition to the routine emission control measurements.
•Variation of the aerosol chemical composition and sulfate fraction with RH.•Aerosol extinction enhances with accumulation of sulfate and nitrate.•Considering hygroscopic growth significantly improves the Vis–PM relationship.•Implication of sulfate/nitrate and RH on Vis degradation over coastal China•Quantify contribution of sulfate and nitrate to light extinction in coastal China.
Details
- Title: Subtitle
- Influence of relative humidity on aerosol composition: Impacts on light extinction and visibility impairment at two sites in coastal area of China
- Creators
- W.J Qu - Physical Oceanography Laboratory, Key Laboratory of Ocean–Atmosphere Interaction and Climate in Universities of Shandong, Ocean University of China, Qingdao 266100, ChinaJ Wang - Department of Earth and Atmospheric Sciences, University of Nebraska-Lincoln, Lincoln, NE 68588-0340, USAX.Y Zhang - Key Laboratory for Atmospheric Chemistry, Chinese Academy of Meteorological Sciences, CMA, 46 Zhong Guan Cun S. Ave., Beijing 100081, ChinaD Wang - State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, 10 Fenghui S. Rd., PO Box 17, XiAn 710075, ChinaL.F Sheng - Physical Oceanography Laboratory, Key Laboratory of Ocean–Atmosphere Interaction and Climate in Universities of Shandong, Ocean University of China, Qingdao 266100, China
- Resource Type
- Journal article
- Publication Details
- Atmospheric research, Vol.153, pp.500-511
- Publisher
- Elsevier B.V
- DOI
- 10.1016/j.atmosres.2014.10.009
- ISSN
- 0169-8095
- eISSN
- 1873-2895
- Grant note
- DOI: 10.13039/501100012166, name: National Basic Research Program of China, award: 2011CB403401; DOI: 10.13039/501100001809, name: NSFC, award: 41276009; name: Chinese Ministry of Education's 111 Project, award: B07036
- Language
- English
- Date published
- 02/2015
- Academic Unit
- Physics and Astronomy; Chemical and Biochemical Engineering; Civil and Environmental Engineering
- Record Identifier
- 9984104912002771
Metrics
20 Record Views