HR: 16:30h
AN: A52G-03    [PDF]
TI: Comparison of POAM III Water Vapor Measurements With a Microphysical Model During the SH Winter
AU: * Benson, C
EM: benson@nrl.navy.mil
AF: Naval Research Laboratory, Remote Sensing Division, Washington, DC 20375-5351
AU: Drdla, K
EM: katja@aerosol.arc.nasa.gov
AF: NASA Ames Research Laboratory, Mailstop 245-4, Moffett Field, CA 94035-1000
AU: Nedoluha, G
EM: nedoluha@nrl.navy.mil
AF: Naval Research Laboratory, Remote Sensing Division, Washington, DC 20375-5351
AU: Shettle, E
EM: shettle@nrl.navy.mil
AF: Naval Research Laboratory, Remote Sensing Division, Washington, DC 20375-5351
AU: Hoppel, K
EM: hoppel@wvms.nrl.navy.mil
AF: Naval Research Laboratory, Remote Sensing Division, Washington, DC 20375-5351
AU: Bevilacqua, R
EM: bevilacqua@wvms.nrl.navy.mil
AF: Naval Research Laboratory, Remote Sensing Division, Washington, DC 20375-5351
AB: The Integrated Microphysics and Aerosol Chemistry on Trajectories (IMPACT) model is used to examine processes leading to dehydration in the Southern Polar stratosphere. Air parcels are advected along 3-D trajectories to establish a temperature history throughout the winter season. The temperature history is used by the model to simulate the processes of nucleation, freezing, and uptake of gases onto the aerosol surface. The values of several parameters are varied in order to establish their effects on dehydration and polar stratospheric cloud formation. Model results are compared to water vapor and extinction measurements obtained by the Polar Ozone and Aerosol Measurement (POAM) III instrument. The amount of dehydration at the end of the season is sensitive to minimum temperatures encountered along the trajectories, and therefore to any biases in the temperature minima in the UKMO [or other] assimilation model inputs. Preliminary results show that the model dehydration agrees well with the POAM measurements when ice particle formation is dominated by heterogeneous nucleation.
DE: 0340 Middle atmosphere--composition and chemistry
DE: 0341 Middle atmosphere--constituent transport and chemistry (3334)
SC: Atmospheric Sciences [A]
MN: 2003 Fall Meeting