HR: 0800h
AN: A51E-0123 [Abstracts]
TI: The Effects of Mixing on Evolution of Hydrocarbon Ratios in the Troposphere
AU: * Parrish, D D
EM: David.D.Parrish@noaa.gov
AF: NOAA Aeronomy Laboratory, 325 Broadway R/AL7, Boulder, CO 80305-3328
United States
AU: Stohl, A
EM: ast@nilu.no
AF: NILU, Norwegian Institute for Air Research, P.O. Box 100, Kjeller, N-2027
Norway
AU: Atlas, E L
EM: eatlas@rsmas.miami.edu
AF: RSMAS, University of Miami, RSMAS/MAC, University of Miami
4600 Rickenbacker Causeway, Miami, FL 33149-1098
United States
AU: Goldan, P D
EM: Paul.D.Goldan@noaa.gov
AF: NOAA Aeronomy Laboratory, 325 Broadway R/AL7, Boulder, CO 80305-3328
United States
AU: Kuster, W C
EM: William.C.Kuster@noaa.gov
AF: NOAA Aeronomy Laboratory, 325 Broadway R/AL7, Boulder, CO 80305-3328
United States
AB:
The evolution of hydrocarbon ratios during atmospheric oxidation is often used as a measure of photochemical processing of an
air mass as it is transported away from an emission region. However, mixing of air masses with differing photochemical
histories precludes an unambiguous interpretation of measured hydrocarbon ratios as accurate, quantitative "photochemical
clocks". We examine the interaction of mixing and aging in air masses sampled during the 2004 ICARTT study in the western
Atlantic and the 2002 ITCT 2K2 study in the eastern Pacific. The age spectra of tracers calculated by the particle
dispersion model FLEXPART (Forster et al., 2004) provide a measure of the histories of the sampled hydrocarbons. Guidelines
for the interpretation of hydrocarbon ratios as indicators of photochemical processing will be suggested.
Forster, C., et al. (2004), Lagrangian transport model forecasts and a transport climatology for the Intercontinental
Transport and Chemical Transformation 2002 (ITCT 2K2) measurement campaign, J. Geophys. Res., 109, D07S92,
doi:10.1029/2003JD003589.
DE: 0322 Constituent sources and sinks
DE: 0345 Pollution: urban and regional (0305, 0478, 4251)
DE: 0365 Troposphere: composition and chemistry
DE: 0368 Troposphere: constituent transport and chemistry
SC: Atmospheric Sciences [A]
MN: Fall Meeting 2005