HR: 16:20h
AN: A14C-02 INVITED     [Abstracts]
TI: Simulating the Redistribution of Formaldehyde in Deep Convection Using the Weather Research Forecast Model Coupled With Aqueous Chemistry
AU: * Barth, M C
EM: barthm@ucar.edu
AF: National Center for Atmospheric Research, P. O. Box 3000, Boulder, CO 80307 United States
AU: Kim, S
EM: swan@ucar.edu
AF: National Center for Atmospheric Research, P. O. Box 3000, Boulder, CO 80307 United States
AU: Skamarock, W C
EM: skamaroc@ucar.edu
AF: National Center for Atmospheric Research, P. O. Box 3000, Boulder, CO 80307 United States
AB: Processing of chemical species by deep convection affects climate, air quality, and acid deposition. The transport of species to the upper troposphere (UT) is an important way of venting the planetary boundary layer and for contributing to the production of ozone in the UT. Wet deposition of dissolved species is the primary pathway for removing pollutants from the atmosphere, yet this process also contributes to acid rain. Cloud chemistry, the combination of aqueous-phase chemistry and the modification of gas-phase chemistry due to the separation of reactants when cloud drops are present, and cloud microphysics can play an important role in determining the fate of species that participate in ozone chemistry. The fate of formaldehyde (CH$_2$O) is a combination of transport to the upper troposphere where CH$_2$O contributes to ozone formation and of cloud scavenging with subsequent rain out or chemical reaction. By coupling a simple chemical reaction mechanism with the Weather and Research Forecast (WRF) model to simulate the 10 July 1996 STERAO storm which was observed in northeastern Colorado, we examine the relative importance of different chemical and physical cloud processes on formaldehyde concentrations. The specific processes studied include aqueous chemistry and retention of CH$_2$O in frozen hydrometeors. The sensitivity of the modeled processes to the microphysics parameterization will be discussed.
DE: 0300 ATMOSPHERIC COMPOSITION AND STRUCTURE
DE: 0320 Cloud physics and chemistry
DE: 0365 Troposphere--composition and chemistry
DE: 0368 Troposphere--constituent transport and chemistry
SC: Atmospheric Sciences [A]
MN: 2004 AGU Fall Meeting