Health & Environmental Research Online (HERO)


Print Feedback Export to File
1056133 
Journal Article 
Winter ozone formation and VOC incremental reactivities in the Upper Green River Basin of Wyoming 
Carter, WPL; Seinfeld, JH 
2012 
1 
Atmospheric Environment
ISSN: 1352-2310
EISSN: 1873-2844 
Elsevier 
50 
Elsevier 
255-266 
English 
WOS:000301561100029 
The Upper Green River Basin (UGRB) in Wyoming experiences ozone episodes in the winter when the air is relatively stagnant and the ground is covered by snow. A modeling study was carried out to assess relative contributions of oxides of nitrogen (NOx) and individual volatile organic compounds (VOCs), and nitrous acid (HONO) in winter ozone formation episodes in this region. The conditions of two ozone episodes, one in February 2008 and one in March 2011, were represented using a simplified box model with all pollutants present initially, but with the detailed SAPRC-07 chemical mechanism adapted for the temperature and radiation conditions arising from the high surface albedo of the snow that was present. Sensitivity calculations were conducted to assess effects of varying HONO inputs, ambient VOC speciation, and changing treatments of temperature and lighting conditions. The locations modeled were found to be quite different in VOC speciation and sensitivities to VOC and NOx emissions, with one site modeled for the 2008 episode being highly NOx-sensitive and insensitive to VOCs and HONO, and the other 2008 site and both 2011 sites being very sensitive to changes in VOC and HONO inputs. Incremental reactivity scales calculated for VOC-sensitive conditions in the UGRB predict far lower relative contributions of alkanes to ozone formation than in the traditional urban-based MIR scale and that the major contributors to ozone formation were the alkenes and the aromatics, despite their relatively small mass contributions. The reactivity scales are affected by the variable ambient VOC speciation and uncertainties in ambient HONO levels. These box model calculations are useful for indicating general sensitivities and reactivity characteristics of these winter UGRB episodes, but fully three-dimensional models will be required to assess ozone abatement strategies in the UGRB. (C) 2011 Elsevier Ltd. All rights reserved. 
Winter ozone; Natural gas production; Incremental VOC reactivity; Upper Green River Basin; SAPRC-07 mechanism 
• ISA-Ozone (2013 Final Project Page)
     Considered
     Cited
          3rd Draft
          Final
     Health Effects
• ISA-Ozone (2020 Final Project Page)
     Literature Search Results
     Literature Search - Included
          Keyword Search
               Topic Classified Exposure
     Title-Abstract Screening (SWIFT-AS) - Excluded
          Manually Excluded