HR: 0800h
AN: A21A-0016    [Abstracts]
TI: Temperature Dependent Alkyl Nitrate Formation
AU: * Shearer, S
EM: sshearer@berkeley.edu
AF: University of California, Berkeley, 667 Davis Hall, Berkeley, CA 94720,
AU: Harley, R
EM: harley@ce.berkeley.edu
AF: University of California, Berkeley, 667 Davis Hall, Berkeley, CA 94720,
AB: In studying the effects of climate change on air quality, it is important to describe correctly the temperature dependence of the relevant atmospheric chemistry. The SAPRC99 chemical mechanism was modified to include missing temperature dependence of alkyl nitrate (RONO2) formation. Alkyl nitrate formation competes with NO to NO2 conversion and hence inhibits production of ozone. We use the Community Multiscale Air Quality model (CMAQ), a three-dimensional regional air quality model, to compare the modified chemical mechanism that includes temperature-dependent RONO2 formation with the base mechanism in Central California. We consider both present day meteorology and a future scenario with perturbed temperatures that are equivalent to a doubling of global background CO2 relative to pre-industrial levels (see Steiner et al., JGR 2006). Changes in predicted alkyl nitrate concentrations (both up and down) follow as expected. NOX and ozone concentrations also change throughout the Central California modeling domain.
DE: 0345 Pollution: urban and regional (0305, 0478, 4251)
DE: 0365 Troposphere: composition and chemistry
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting