dc.contributor.author | Dusanter, S. | |
dc.contributor.author | Vimal, D. | |
dc.contributor.author | Stevens, P. S. | |
dc.contributor.author | Volkamer, R. | |
dc.contributor.author | Molina, Luisa Tan | |
dc.contributor.author | Baker, A. | |
dc.contributor.author | Meinardi, S. | |
dc.contributor.author | Blake, D. | |
dc.contributor.author | Merten, A. | |
dc.contributor.author | Zhang, R. | |
dc.contributor.author | Zheng, J. | |
dc.contributor.author | Fortner, E. C. | |
dc.contributor.author | Junkermann, W. | |
dc.contributor.author | Dubey, Madan | |
dc.contributor.author | Rahn, T. | |
dc.contributor.author | Eichinger, B. | |
dc.contributor.author | Lewandowski, P. | |
dc.contributor.author | Prueger, J. | |
dc.contributor.author | Holder, H. | |
dc.contributor.author | Sheehy, P. M. | |
dc.date.accessioned | 2012-01-03T20:55:05Z | |
dc.date.available | 2012-01-03T20:55:05Z | |
dc.date.issued | 2009-09 | |
dc.date.submitted | 2009-08 | |
dc.identifier.issn | 1680-7324 | |
dc.identifier.issn | 1680-7316 | |
dc.identifier.uri | http://hdl.handle.net/1721.1/67896 | |
dc.description.abstract | Measurements of hydroxyl (OH) and hydroperoxy (HO2) radicals were made during the Mexico City Metropolitan Area (MCMA) field campaign as part of the MILAGRO (Megacity Initiative: Local and Global Research Observations) project during March 2006. These measurements provide a unique opportunity to test current models of atmospheric ROx (OH + HO2 + RO2) photochemistry under polluted conditions. A zero-dimensional box model based on the Regional Atmospheric Chemical Mechanism (RACM) was constrained by 10-min averages of 24 J-values and the concentrations of 97 chemical species. Several issues related to the ROx chemistry under polluted conditions are highlighted in this study: (i) Measured concentrations of both OH and HO2 were underpredicted during morning hours on a median campaign basis, suggesting a significant source of radicals is missing from current atmospheric models under polluted conditions, consistent with previous urban field campaigns. (ii) The model-predicted HO2/OH ratios underestimate the measurements for NO mixing ratios higher than 5 ppb, also consistent with previous urban field campaigns. This suggests that under high NOx conditions, the HO2 to OH propagation rate may be overestimated by the model or a process converting OH into HO2 may be missing from the chemical mechanism. On a daily basis (08:40 a.m.–06:40 p.m.), an analysis of the radical budget indicates that HONO photolysis, HCHO photolysis, O3-alkene reactions and dicarbonyls photolysis are the main radical sources. O3 photolysis contributes to less than 6% of the total radical production. | en_US |
dc.description.sponsorship | Henry & Camille Dreyfus Foundation | en_US |
dc.description.sponsorship | National Science Foundation (U.S.) (ATM-9984152) | en_US |
dc.description.sponsorship | National Science Foundation (U.S.) (0612738) | en_US |
dc.language.iso | en_US | |
dc.publisher | Copernicus Publications on behalf of the European Geosciences Union | en_US |
dc.relation.isversionof | http://dx.doi.org/10.5194/acp-9-6655-2009 | en_US |
dc.rights | Creative Commons Attribution 3.0 | en_US |
dc.rights.uri | http://creativecommons.org/licenses/by/3.0 | en_US |
dc.source | Copernicus | en_US |
dc.title | Measurements of OH and HO2 concentrations during the MCMA-2006 field campaign – Part 2: Model comparison and radical budget | en_US |
dc.type | Article | en_US |
dc.identifier.citation | Dusanter, S. et al. “Measurements of OH and HO2 concentrations during the MCMA-2006 field campaign – Part 2: Model comparison and radical budget.” Atmospheric Chemistry and Physics 9.18 (2009): 6655-6675. | en_US |
dc.contributor.department | Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences | en_US |
dc.contributor.approver | Molina, Luisa Tan | |
dc.contributor.mitauthor | Molina, Luisa Tan | |
dc.contributor.mitauthor | Sheehy, P. | |
dc.relation.journal | Atmospheric Chemistry and Physics | en_US |
dc.eprint.version | Final published version | en_US |
dc.type.uri | http://purl.org/eprint/type/JournalArticle | en_US |
eprint.status | http://purl.org/eprint/status/PeerReviewed | en_US |
dspace.orderedauthors | Dusanter, S.; Vimal, D.; Stevens, P. S.; Volkamer, R.; Molina, L. T.; Baker, A.; Meinardi, S.; Blake, D.; Sheehy, P.; Merten, A.; Zhang, R.; Zheng, J.; Fortner, E. C.; Junkermann, W.; Dubey, M.; Rahn, T.; Eichinger, B.; Lewandowski, P.; Prueger, J.; Holder, H. | en |
dc.identifier.orcid | https://orcid.org/0000-0002-3596-5334 | |
mit.license | PUBLISHER_CC | en_US |
mit.metadata.status | Complete | |