HR: 10:50h
AN: A12C-03    [Abstracts]
TI: Evaluation of the Volatility Basis-Set Approach for Modeling Primary and Secondary Organic Aerosol in the Mexico City Metropolitan Area
AU: * Tsimpidi, A P
EM: tsimpidi@chemeng.upatras.gr
AF: Dept. of Chemical Engineering, University of Patras, 1 Karatheodori,Rio, Patra, 26504, Greece
AU: Karydis, V A
EM: vlkarydis@chemeng.upatras.gr
AF: Dept. of Chemical Engineering, University of Patras, 1 Karatheodori,Rio, Patra, 26504, Greece
AU: Pandis, S N
EM: spyros@chemeng.upatras.gr
AF: Dept. of Chemical Engineering, University of Patras, 1 Karatheodori,Rio, Patra, 26504, Greece
AU: Zavala, M
EM: miguelz@MIT.EDU
AF: Dept. of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology (MIT), 77 Massachusetts Avenue, Cambridge, MA 02139, United States
AU: Zavala, M
EM: miguelz@MIT.EDU
AF: Molina Center for Energy and the Environment (MCE2), 3262 Holiday Ct., Suite 2001, La Jolla, CA 92037, United States
AU: Lei, W
EM: wflei@MIT.EDU
AF: Dept. of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology (MIT), 77 Massachusetts Avenue, Cambridge, MA 02139, United States
AU: Lei, W
EM: wflei@MIT.EDU
AF: Molina Center for Energy and the Environment (MCE2), 3262 Holiday Ct., Suite 2001, La Jolla, CA 92037, United States
AU: Molina, L T
EM: ltmolina@MIT.EDU
AF: Dept. of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology (MIT), 77 Massachusetts Avenue, Cambridge, MA 02139, United States
AU: Molina, L T
EM: ltmolina@MIT.EDU
AF: Molina Center for Energy and the Environment (MCE2), 3262 Holiday Ct., Suite 2001, La Jolla, CA 92037, United States
AB: Anthropogenic air pollution is an increasingly serious problem for public health, agriculture, and global climate. Organic material (OM) contributes ~ 20-50% to the total fine aerosol mass at continental mid-latitudes. Although OM accounts for a large fraction of PM2.5 concentration worldwide, the contributions of primary and secondary organic aerosol have been difficult to quantify. In this study, new primary and secondary organic aerosol modules were added to PMCAMx, a three dimensional chemical transport model (Gaydos et al., 2007), for use with the SAPRC99 chemistry mechanism (Carter, 2000; ENVIRON, 2006) based on recent smog chamber studies (Robinson et al., 2007). The new modeling framework is based on the volatility basis-set approach (Lane et al., 2007): both primary and secondary organic components are assumed to be semivolatile and photochemically reactive and are distributed in logarithmically spaced volatility bins. The emission inventory, which uses as starting point the MCMA 2004 official inventory (CAM, 2006), is modified and the primary organic aerosol (POA) emissions are distributed by volatility based on dilution experiments (Robinson et al., 2007). Sensitivity tests where POA is considered as nonvolatile and POA and SOA as chemically reactive are also described. In all cases PMCAMx is applied in the Mexico City Metropolitan Area during March 2006. The modeling domain covers a 180x180x6 km region in the MCMA with 3x3 km grid resolution. The model predictions are compared with Aerodyne's Aerosol Mass Spectrometry (AMS) observations from the MILAGRO Campaign. References Robinson, A. L.; Donahue, N. M.; Shrivastava, M. K.; Weitkamp, E. A.; Sage, A. M.; Grieshop, A. P.; Lane, T. E.; Pandis, S. N.; Pierce, J. R., 2007. Rethinking organic aerosols: semivolatile emissions and photochemical aging. Science 315, 1259-1262. Gaydos, T. M.; Pinder, R. W.; Koo, B.; Fahey, K. M.; Pandis, S. N., 2007. Development and application of a three- dimensional aerosol chemical transport model, PMCAMx. Atmospheric Environment 41, 2594-2611. Carter, W.P.L., 2000. Programs and Files Implementing the SAPRC-99 Mechanism and its Associates Emissions Processing Procedures for Models-3 and Other Regional Models. January 31, 2000. http://pah.cert.ucr.edu/~carter/SAPRC99.htm. Environ, 2006. User's guide to the comprehensive air quality model with extensions (CAMx). Version 4.30. Report prepared by ENVIRON International Corporation, Novato, CA. Lane, T.E.; Donahue, N. M.; Pandis, S. N. 2007. Simulating Secondary Organic Aerosol Formation using the Votality Basis-Set Approach in a Chemical Transport Model, in preperation. CAM (Comision Ambiental Metropolitana) 2006: Inventario de Emisiones 2004 de la Zona Metropolitana del Valle de Mexico, Mexico. Robinson, A. L.; Donahue, N. M.; Shrivastava, M. K.; Weitkamp, E. A.; Sage, A. M.; Grieshop, A. P.; Lane, T. E.; Pandis, S. N.; Pierce, J. R., 2007. Rethinking organic aerosols: semivolatile emissions and photochemical aging. Science 315, 1259-1262.
DE: 0305 Aerosols and particles (0345, 4801, 4906)
DE: 0345 Pollution: urban and regional (0305, 0478, 4251)
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting