Title:
A comparison of NMHC oxidation mechanisms using specified gas mixtures and trace-P field data

dc.contributor.advisor Davis, Douglas Dale
dc.contributor.author Gong, Xingyi en_US
dc.contributor.committeeMember Cunnold, Derek
dc.contributor.committeeMember Mulholland, James
dc.contributor.committeeMember Wang, Yuhang
dc.contributor.committeeMember Wine, Paul
dc.contributor.department Earth and Atmospheric Sciences en_US
dc.date.accessioned 2006-01-18T22:18:11Z
dc.date.available 2006-01-18T22:18:11Z
dc.date.issued 2005-11-15 en_US
dc.description.abstract This work has focused on showing the differences among four different NMHC oxidation mechanisms: GT Lurmann, CBIV, RACM, and SAPRC mechanisms. This study was carried out to characterize these mechanisms using both specified NOx/NMHC gas mixtures and observational data from NASAs TRACE-P campaign. The differences among these mechanisms were found to be mainly driven by the use of different kinetic data and the specifics of each oxidation scheme. In the test runs, the differences between mechanisms were shown to be dependent on the levels of NOx and NMHC, as well as the reactivity of NMHC species used. Typically, propane had the smallest impact on all product species, whereas propene had the largest. Differences in the predicted levels of OH and HO2 were much smaller compared to those for CH3O2 and CH2O due to the fact that HOx species were generally less sensitive to the presence of NMHCs. During TRACE-P, which involved flights over only marine areas that were slightly polluted by the inflow of pollutants, the alkanes were the dominant NMHC family. Thus, most of the model runs involved relatively low levels of NMHCs and NOx. Therefore, the levels of OH, HO2, CH3O2, and CH2O predicted by the four mechanisms were not dramatically different. A net O3 increase was found only in areas where the NMHC reactivity was high. Because of the similar O3 destruction rates given by all four mechanisms, the difference in O3 tendency among these mechanisms was mainly determined by the O3 formation rate. A significantly higher (e.g., ~30%) O3 formation was found in the Lurmann mechanism than in CBIV due to the stronger contribution from the NO/RO2 channel in this mechanism. This resulted in a difference in the O3 tendency of a factor of 1.5. A major need in terms of future studies will be that of examining these same four mechanisms with a data set that enfolds observations in more polluted regions. en_US
dc.description.degree Ph.D. en_US
dc.format.extent 2838571 bytes
dc.format.mimetype application/pdf
dc.identifier.uri http://hdl.handle.net/1853/7512
dc.language.iso en_US
dc.publisher Georgia Institute of Technology en_US
dc.subject Controlled test en_US
dc.subject Hydrocarbons Oxidation
dc.subject Intercomparison
dc.subject Modeling
dc.subject Photochemistry
dc.subject Tropospheric chemistry
dc.title A comparison of NMHC oxidation mechanisms using specified gas mixtures and trace-P field data en_US
dc.type Text
dc.type.genre Dissertation
dspace.entity.type Publication
local.contributor.corporatename School of Earth and Atmospheric Sciences
local.contributor.corporatename College of Sciences
relation.isOrgUnitOfPublication b3e45057-a6e8-4c24-aaaa-fb00c911603e
relation.isOrgUnitOfPublication 85042be6-2d68-4e07-b384-e1f908fae48a
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