HR: 15:25h
AN: SA13B-08    [Abstracts]
TI: Numerical simulations of the three-dimensional distribution of polar mesospheric clouds using WACCM/CARMA
AU: * Bardeen, C G
EM: bardeenc@colorado.edu
AF: University of Colorado / LASP, Campus Box 392, Boulder, CO 80309, United States
AU: Toon, O B
EM: Brian.Toon@lasp.colorado.edu
AF: University of Colorado / LASP, Campus Box 392, Boulder, CO 80309, United States
AU: Jensen, E J
EM: ejensen@sky.arc.nasa.gov
AF: NASA Ames Research Center, MS 245-4, Moffett Field, CA 94305, United States
AU: Benze, S
EM: Susanne.Benze@lasp.colorado.edu
AF: University of Colorado / LASP, Campus Box 392, Boulder, CO 80309, United States
AU: Marsh, D R
EM: marsh@ucar.edu
AF: National Center for Atmospheric Research, PO Box 3000, Boulder, CO 80307-5000, United States
AU: Randall, C E
EM: Cora.Randall@Colorado.EDU
AF: University of Colorado / LASP, Campus Box 392, Boulder, CO 80309, United States
AU: Merkel, A W
EM: Aimee.Merkel@lasp.colorado.edu
AF: University of Colorado / LASP, Campus Box 392, Boulder, CO 80309, United States
AU: Merkel, A W
EM: Aimee.Merkel@lasp.colorado.edu
AF: National Center for Atmospheric Research, PO Box 3000, Boulder, CO 80307-5000, United States
AB: Polar mesospheric clouds (PMC) are ice clouds that routinely form in the cold summer mesopause region; however, the nucleation mechanism for these clouds is not well understood. Several possible condensation nuclei have been identified including: meteoric dust, ion clusters, sulfate aerosols, soot, sodium bicarbonate and sodium hydroxide. Recent studies have shown that fewer large meteoric dust particles may be present in the summer mesopause region than have previously been assumed to be necessary for the nucleation of PMCs. We use WACCM/CARMA, a three-dimensional chemistry climate model based upon the Whole-Atmosphere Community Climate Model (WACCM) with sectional microphysics from the Community Aerosol and Radiation Model for Atmospheres (CARMA) to study the distribution and characteristics of PMCs formed by heterogeneous nucleation with meteoric dust particles. The distribution of meteoric dust particles in the model is also calculated using sectional microphysics and is based upon a source of recondensed material from the ablation of micrometeoroids. Results from these simulations are compared with several observations including those from the Aeronomy of Ice in the Mesosphere (AIM) mission, the Solar Backscatter Ultraviolet (SBUV) instrument and the Student Nitric Oxide Explorer (SNOE) satellite and with results from other models.
DE: 0305 Aerosols and particles (0345, 4801, 4906)
DE: 0320 Cloud physics and chemistry
DE: 0340 Middle atmosphere: composition and chemistry
DE: 0341 Middle atmosphere: constituent transport and chemistry (3334)
DE: 3332 Mesospheric dynamics
SC: SPA-Aeronomy [SA]
MN: 2007 Fall Meeting