DOI: 10.1002/2015JD024508
论文题名: Characterization of organic residues of size-resolved fog droplets and their atmospheric implications
作者: Chakraborty A. ; Ervens B. ; Gupta T. ; Tripathi S.N.
刊名: Journal of Geophysical Research: Atmospheres
ISSN: 2169897X
出版年: 2016
卷: 121, 期: 8 起始页码: 4317
结束页码: 4332
语种: 英语
英文关键词: AMS
; fog
; organics
英文摘要: Size-resolved fog water samples were collected in two consecutive winters at Kanpur, a heavily polluted urban area of India. Samples were analyzed by an aerosol mass spectrometer after drying and directly in other instruments. Residues of fine fog droplets (diameter: 4-16 μm) are found to be more enriched with oxidized (oxygen to carbon ratio, O/C = 0.88) and low volatility organics than residues of coarse (diameter > 22 μm) and medium size (diameter: 16-22 μm) droplets with O/C of 0.68 and 0.74, respectively. These O/C ratios are much higher than those observed for background ambient organic aerosols, indicating efficient oxidation in fog water. Accompanying box model simulations reveal that longer residence times, together with high aqueous OH concentrations in fine droplets, can explain these trends. High aqueous OH concentrations in smaller droplets are caused by their highest surface-volume ratio and high Fe and Cu concentrations, allowing more uptake of gas phase OH and enhanced Fenton reaction rates, respectively. Although some volatile organic species may have escaped during droplet evaporation, these findings indicate that aqueous processing of dissolved organics varies with droplet size. Therefore, large (regional, global)-scale models need to consider the variable reaction rates, together with metal-catalyzed radical formation throughout droplet populations for accurately predicting aqueous secondary organic aerosol formation. ©2016. American Geophysical Union. All Rights Reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/62906
Appears in Collections: 影响、适应和脆弱性 气候减缓与适应
There are no files associated with this item.
作者单位: Department of Civil Engineerin, Indian Institute of Technology, Kanpur, India; CIRES, University of Colorado, Boulder, CO, United States; NOAA, ESRL, CSD, Boulder, CO, United States; Centre for Environmental Science and Engineering, Indian Institute of Technology, Kanpur, India
Recommended Citation:
Chakraborty A.,Ervens B.,Gupta T.,et al. Characterization of organic residues of size-resolved fog droplets and their atmospheric implications[J]. Journal of Geophysical Research: Atmospheres,2016-01-01,121(8)