DOI: 10.1002/2017JD027709
Scopus记录号: 2-s2.0-85045189638
论文题名: Changes in Atmospheric Butanes and Pentanes and Their Isomeric Ratios in the Continental United States
作者: Rossabi S. ; Helmig D.
刊名: Journal of Geophysical Research: Atmospheres
ISSN: 2169897X
出版年: 2018
卷: 123, 期: 7 起始页码: 3772
结束页码: 3790
语种: 英语
英文关键词: atmospheric
; butanes
; isomeric ratio
; pentanes
; trends
Scopus关键词: atmospheric chemistry
; concentration (composition)
; emission
; mixing ratio
; nonmethane hydrocarbon
; pollutant source
; time series
; trend analysis
; United States
英文摘要: Nonmethane hydrocarbons have been used as tracers in research on emissions and atmospheric oxidation chemistry. This research investigates source region mixing ratio trends of the nonmethane hydrocarbons i-butane, n-butane, i-pentane, and n-pentane, and the (i/n) isomeric ratios of these compounds between 2001 and 2015. Data collected at Photochemical Assessment Monitoring Stations, mandated by the U.S. Environmental Protection Agency in ozone nonattainment areas, and data collected at Global Greenhouse Gas Reference Network sites within the National Oceanic and Atmospheric Administration network, and analyzed at the Institute of Arctic and Alpine Research at the University of Colorado-Boulder, were examined. Among all considered species, linear regression analyses on concentration time series had negative slopes at 81% of sites, indicating predominantly declining butane and pentane atmospheric concentrations. Mostly negative slopes (78% of sites) were found for the (i/n) butane and pentane isomeric ratios, including all six and seven statistically significant (i/n) butane and pentane trends, respectively. Over the ~15 year investigation period and averaged over all sites, total relative changes were ~30 and 45% for the (i/n) ratios of butanes and pentanes, respectively, with a relative increase in the prominence of the n-isomers. Most likely causes include changing isomeric ratios in gasoline sector emissions, and increasing influence of oil and natural gas industry emissions. Changes in concentrations and isomeric ratios depend on proximity of contributing emission sources to measurement sites. ©2018. 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/114101
Appears in Collections: 气候减缓与适应
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作者单位: Institute of Arctic and Alpine Research (INSTAAR), University of Colorado Boulder, Boulder, CO, United States
Recommended Citation:
Rossabi S.,Helmig D.. Changes in Atmospheric Butanes and Pentanes and Their Isomeric Ratios in the Continental United States[J]. Journal of Geophysical Research: Atmospheres,2018-01-01,123(7)