HR: 0800h
AN: A41B-0429    [Abstracts]
TI: Study of Light Scattering and Reflectance by an Atmosphere with Nonspherical Mineral Dust Aerosols
AU: * Feng, Q
EM: fengqian@ariel.met.tamu.edu
AF: Department of atmospheric sciences, Texas A&M University, College Station, TX 77843,
AU: Yang, P
EM: pyang@ariel.met.tamu.edu
AF: Department of atmospheric sciences, Texas A&M University, College Station, TX 77843,
AU: Kattawar, G
EM: kattawar@physics.tamu.edu
AF: Department of Physics, Texas A&M University, College Station, TX 77843,
AU: Laszlo, I
EM: Istvan.Laszlo@noaa.gov
AF: Office of Research and Applications, NOAA/NESDIS, Camp Spring, MD 20746,
AB: The scattering properties of dust aerosols assumed to be a mixture of randomly oriented spheroids with size and shape distributions are simulated with a composite method based on the T-matrix method and the geometric optics method (GOM). The T-matrix method is used only for small and moderate particles, whereas the GOM is applicable to large particles. The performance of this composite method used for the simulation of scattering properties of nonspherical dust aerosols is tested and evaluated based on measured scattering matrix of feldspar particles. The comparison between simulated and measurement indicates that use of spheroids with size and shape distributions can be a reasonable approach for estimating the scattering properties of nonspherical dust aerosols. Furthermore, Reflectance by an atmosphere containing nonspherical dust aerosols based on a polarized radiative transfer model is calculated, and sensitivity studies with respect to aerosol optical depth and particle sizes are carried out. Reflectance differences between vector and scalar radiative transfer models under different conditions are also discussed.
DE: 0305 Aerosols and particles (0345, 4801, 4906)
DE: 0360 Radiation: transmission and scattering
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting