HR: 14:25h
AN: A33G-04    [Abstracts]
TI: SOA Formation by Chemical Processes in Cloud Droplets
AU: * Ervens, B
EM: barbara.ervens@noaa.gov
AF: Colorado State University, 200 West Lake Street, Fort Collins, CO 80523, United States
AU: * Ervens, B
EM: barbara.ervens@noaa.gov
AF: ESRL NOAA, 325 Broadway, Boulder, CO 80305, United States
AU: Carlton, A G
EM: carlton.annmarie@epamail.epa.gov
AF: ASMD ARL NOAA, Mail Drop E-243-01, Res. Triangle Park, NC 27711, United States
AU: Turpin, B J
EM: turpin@envsci.rutgers.edu
AF: Department of Environmental Sciences, Rutgers University, 71 Dudley Road, New Brunswick, NJ 08901, United States
AU: Altieri, K E
EM: altieri@marine.rutgers.edu
AF: Institute of Marine and Coastal Sciences, Rutgers University, 71 Dudley Road, New Brunswick, NJ 08901, United States
AU: Kreidenweis, S M
EM: sonia@atmos.colostate.edu
AF: Colorado State University, 200 West Lake Street, Fort Collins, CO 80523, United States
AU: Feingold, G
EM: graham.feingold@noaa.gov
AF: ESRL NOAA, 325 Broadway, Boulder, CO 80305, United States
AB: While there is a growing understanding from laboratory studies of aqueous-phase chemical processes that lead to secondary organic aerosol (SOA) formation in cloud droplets ('SOAdrop'), the extent of which in-cloud chemistry contributes to atmospheric SOA burden and modifies the composition and size distribution of pre-existing aerosol populations by cloud-processing is not quantified yet. Using a parcel model including a multiphase chemical mechanism, we show that SOAdrop yields (Yc) from several precursors (e.g., isoprene and water- soluble oxidation products) (i) depend strongly on the initial volatile organic carbon (VOC)/NOx ratio; (ii) increase in longer-lived clouds; (iii) are not greatly affected by cloud liquid water content, pH, and droplet number and (iv) change little within realistic variability of gas-particle partitioning of semivolatile organics outside of clouds. We will present parameterized expressions of SOAdrop yields that can be easily applied to air quality and climate models as is done with SOA formed on/in haze particles ('SOAhaze').
DE: 0305 Aerosols and particles (0345, 4801, 4906)
DE: 0317 Chemical kinetic and photochemical properties
DE: 0320 Cloud physics and chemistry
DE: 0365 Troposphere: composition and chemistry
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting