HR: 0830h
AN: A11E-0036    [PDF]
TI: Modeling the Big Bend Regional Aerosol and Visibility Observational (BRAVO) Study using CMAQ-MADRID
AU: * Knipping, E M
EM: eknippin@epri.com
AF: EPRI, 3412 Hillview Ave, Palo Alto, CA 94304 United States
AU: Kumar, N
EM: nkumar@epri.com
AF: EPRI, 3412 Hillview Ave, Palo Alto, CA 94304 United States
AU: Pun, B
EM: bpun@aer.com
AF: Atmospheric & Environmental Research, Inc, 2682 Bishop Drive, Suite 120, San Ramon, CA 94583 United States
AU: Wu, S
EM: swu@aer.com
AF: Atmospheric & Environmental Research, Inc, 2682 Bishop Drive, Suite 120, San Ramon, CA 94583 United States
AU: Seigneur, C
EM: cseigneu@aer.com
AF: Atmospheric & Environmental Research, Inc, 2682 Bishop Drive, Suite 120, San Ramon, CA 94583 United States
AB: A scientifically rigorous treatment of particulate matter within the framework of the Community Multiscale Air Quality (CMAQ) model is provided by CMAQ-MADRID (Model for Aerosol Dynamics, Reaction, Ionization, and Dissolution). CMAQ-MADRID is used to simulate the fate and transport of ambient gases and particulate matter (PM) during the Big Bend Regional Aerosol and Visibility Observational (BRAVO) study. The configuration of CMAQ-MADRID used for this study comprises the Regional Acid Deposition Mechanism v.2 (RADM2) gas-phase chemistry mechanism, a sectional PM solver incorporating the ISORROPIA inorganic thermodynamics module and the AER/EPRI/Caltech (AEC) secondary organic aerosol (SOA) module, and the Carnegie Mellon University (CMU) cloud chemistry module. Boundary conditions for gas- and particle-phase species are prescribed by an outer domain simulated using the Regional Modeling System for Aerosols and Deposition REMSAD (whose domain comprises most of North America). Sulfur dioxide (SO$_{2}$) and particulate sulfate boundary conditions for the REMSAD domain are provided by the Georgia Tech/Goddard Global Ozone Chemistry Aerosol Radiation Transport (GOCART) model. Concentrations of sulfur dioxide and particulate sulfate at the CMAQ boundary are scaled to observations from monitoring stations of the Clean Air Status and Trends Network (CASTNet) and Interagency Monitoring of Protected Visual Environments (IMPROVE) network. The performance of CMAQ-MADRID is evaluated by comparing predictions with field measurements of the principal components contributing to visibility degradation: salts of ammonium with sulfate and nitrate, organic mass, elemental carbon and "other" particulate matter constituents, e.g. dust, sea salt and metal oxides. Model performance with respect to sulfate predictions, including model performance for its gas-phase precursor, sulfur dioxide, is explored across the thirty-seven stations comprising the BRAVO Network. The performance of CMAQ-MADRID in simulating total fine particulate matter across the BRAVO Network is also investigated. Detailed diagnostic analyses of model performance, including comparison between observed/simulated trends, are performed for fine particulate matter and its main components (SO$_{4}$$^{2-}$, NO$_{3}$$^{-}$, NH$_{4}$$^{+}$, OM, EC and "other") at Big Bend National Park. Potential causes for discrepancies between model predictions and observations during the BRAVO study are discussed.
DE: 0300 ATMOSPHERIC COMPOSITION AND STRUCTURE
DE: 0305 Aerosols and particles (0345, 4801)
DE: 0345 Pollution--urban and regional (0305)
DE: 0368 Troposphere--constituent transport and chemistry
DE: 3337 Numerical modeling and data assimilation
SC: Atmospheric Sciences [A]
MN: 2003 Fall Meeting