HR: 0800h
AN: A51B-0036    [Abstracts]
TI: Uncertain Isoprene Emissions and Chemistry: Implications for Ozone in the Eastern United States
AU: * Fiore, A M
EM: arlene.fiore@noaa.gov
AF: NOAA Geophysical Fluid Dynamics Lab, 201 Forrestal Road, Princeton, NJ 08540 United States
AU: Horowitz, L W
EM: Larry.Horowitz@noaa.gov
AF: NOAA Geophysical Fluid Dynamics Lab, 201 Forrestal Road, Princeton, NJ 08540 United States
AU: Milly, G
EM: George.Milly@noaa.gov
AF: NOAA Geophysical Fluid Dynamics Lab, 201 Forrestal Road, Princeton, NJ 08540 United States
AU: Cohen, R C
EM: cohen@cchem.berkeley.edu
AF: University of California Berkeley, Department of Chemistry Latimer Hall , Berkeley, CA 94720-1460 United States
AU: Avery, M A
EM: m.a.avery@larc.nasa.gov
AF: NASA Langley Research Center, Chemistry and Dynamics Branch, Hampton, VA 23681-0001
AU: Blake, D R
EM: drblake@uci.edu
AF: University of California Irvine, Department of Chemistry , Irvine, CA 92697-2025
AU: Emmons, L K
EM: emmons@ucar.edu
AF: National Center for Atmospheric Research, Atmospheric Chemistry Division P.O. Box 3000, Boulder, CO 80307-3000 United States
AU: Fried, A
EM: fried@ucar.edu
AF: National Center for Atmospheric Research, Atmospheric Chemistry Division P.O. Box 3000, Boulder, CO 80307-3000 United States
AU: Hess, P
EM: hess@ucar.edu
AF: National Center for Atmospheric Research, Atmospheric Chemistry Division P.O. Box 3000, Boulder, CO 80307-3000 United States
AU: Lamarque, J
EM: lamar@ucar.edu
AF: National Center for Atmospheric Research, Atmospheric Chemistry Division P.O. Box 3000, Boulder, CO 80307-3000 United States
AU: Perring, A
EM: aperring@berkeley.edu
AF: University of California Berkeley, Department of Chemistry Latimer Hall , Berkeley, CA 94720-1460 United States
AU: Pfister, G G
EM: pfister@ucar.edu
AF: National Center for Atmospheric Research, Atmospheric Chemistry Division P.O. Box 3000, Boulder, CO 80307-3000 United States
AU: Singh, H B
EM: Hanwant.B.Singh@nasa.gov
AF: NASA Ames Research Center , MS 245-5 , Moffett Field, CA 94035 United States
AU: Walega, J
EM: walega@ucar.edu
AF: National Center for Atmospheric Research, Atmospheric Chemistry Division P.O. Box 3000, Boulder, CO 80307-3000 United States
AU: Wooldridge, P
EM: pjwool@Socrates.berkeley.edu
AF: University of California Berkeley, Department of Chemistry Latimer Hall , Berkeley, CA 94720-1460 United States
AB: Uncertainties in isoprene emissions and chemistry confound efforts to quantitatively address the role of isoprene in eastern U.S. air quality. In particular, differences in current isoprene emission inventories and in the representation of organic isoprene nitrates (their yield and fate) in chemical mechanisms are shown to substantially influence estimates of surface ozone over the eastern United States, locally by up to 15 and 12 ppbv, respectively. The largest uncertainties occur in the high isoprene-emitting southeastern United States. During the summer 2004 ICARTT aircraft campaign over the eastern United States, isoprene and a suite of its oxidation products were measured, including formaldehyde, individual and total alkyl nitrates and peroxynitrates. We conduct sensitivity simulations with the MOZART-4 tropospheric chemistry model in which we vary isoprene emissions (GEIA, MEGAN inventories) and treatments of isoprene nitrates (the yield and the fraction recycling to NO_x). We analyze these simulations, in conjunction with the ICARTT measurements, to gain insights into isoprene-NO_x-ozone chemistry over the eastern United States, and to attempt to constrain the isoprene emissions and the yield and fate of isoprene nitrates.
DE: 0315 Biosphere/atmosphere interactions (0426, 1610)
DE: 0322 Constituent sources and sinks
DE: 0345 Pollution: urban and regional (0305, 0478, 4251)
SC: Atmospheric Sciences [A]
MN: Fall Meeting 2005