HR: 11:56h
AN: A22A-08    [Abstracts]
TI: Heterogeneity of ozone yield with location of nitrogen oxide emission origin
AU: * Cohan, D S
EM: dcohan@eas.gatech.edu
AF: School of Earth & Atmospheric Sciences Georgia Institute of Technology, 311 Ferst Drive, Atlanta, GA 30332 United States
AU: Russell, A G
EM: trussell@ce.gatech.edu
AF: School of Civil & Environmental Engineering Georgia Institute of Technology, 311 Ferst Drive, Atlanta, GA 30332 United States
AB: Considering a summertime air pollution episode in Georgia as a case study, we examine how ozone accumulation efficiency and distance of impact depend on the intensity of a NOx source, its elevation above ground level, and its location within the state. The High-order Decoupled Direct Method in Three Dimensions (HDDM-3D) is applied in Community Multiscale Air Quality model simulations to quantify ozone accumulation efficiency by three metrics. In addition, distance of impact for each NOx source region is quantified by computing the first moment of associated ozone accumulation; the first moments are found to be similar across source regions in Georgia (140-210 km). We find that two mid-sized metropolitan regions in Georgia yield 40-70 percent more ground-level ozone per ton of NOx than two large power plants, and 20 percent more per ton than the Atlanta region, consistent with the lower emissions intensities of the mid-sized regions. However, we find that the heterogeneity of ozone yield for various locations within the Atlanta region can be even greater than the differences among regional averages. Heterogeneity of response to Atlanta emissions becomes far more pronounced if ozone accumulation is weighted by population, indicating that the per ton impact of a NOx source on potential population exposure is highly dependent on emission location. We discuss how small-scale heterogeneity of ozone yield and potential population impact complicate the formulation of sensible abatement and trading policies.
DE: 3307 Boundary layer processes
DE: 0345 Pollution--urban and regional (0305)
DE: 0368 Troposphere--constituent transport and chemistry
SC: Atmospheric Sciences [A]
MN: 2004 AGU Fall Meeting