HR: 0830h
AN: A11E-0011    [PDF]
TI: The Effect of Non-sphericity on GOES-8 Dust Aerosol Retrievals During PRIDE
AU: * Wang, J
EM: wangjun@nsstc.uah.edu
AF: 1. Department of Atmospheric Sciences, University of Alabama in Huntsville, 320 Sparkman Drive, Huntsville, AL 35805
AU: Christopher, S A
EM: sundar@nsstc.uah.edu
AF: 1. Department of Atmospheric Sciences, University of Alabama in Huntsville, 320 Sparkman Drive, Huntsville, AL 35805
AU: Liu, X
EM: xliu@cfa.harvard.edu
AF: 2 Atomic and Molecular Physics Division, Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Mail Stop 50, Cambridge, MA 02138,
AU: Reid, J S
EM: reidj@nrlmry.navy.mil
AF: Marine Meteorology Division, Naval Research Laboratory, 7 Brace Hopper Street, Mail Stop 2, Monterey, CA 93943
AU: Reid, E A
EM: reidb@nrlmry.navy.mil
AF: Marine Meteorology Division, Naval Research Laboratory, 7 Brace Hopper Street, Mail Stop 2, Monterey, CA 93943
AU: Maring, H
EM: hal.maring@nasa.gov
AF: 4. Division of Marine and Atmospheric Chemistry, University of Miami, 4600 Rickenbacker Causeway, Miami, FL 33149
AB: This paper examines the effect of non-spherical phase functions on satellite aerosol retrievals by using a variety of data collected during the Puerto Rico Dust Experiment (PRIDE). Scanning electron micrograph (SEM) analysis was used to build a statistical model to describe dust morphologies [Reid et al., 2003]. By assuming that dust particles are oblate spheroids, the statistical model together with measured size distribution are then used to compute the dust phase function and dust scattering properties through T-matrix calculations. Comparison shows that modeled and measured scattering coefficients, although highly correlated, have 20% discrepancies that cannot be simply ascribed to the uncertainties (10%) of light scattering measurements. Such discrepancy could either from size distribution measurements or the lack of full consideration of dust irregular shapes. The modeled non-spherical function however favorably agrees the synthetic non-spherical phase function [Liu et al., 2003]. The non-spherical phase function is then used to replace the spherical phase function for the GOES8 aerosol retrievals. New dust AOT retrievals however only show slightly improvement at certain scattering angles. Further analysis shows that using composite phase function by considering both spherical and non-spherical particles can greatly improve the retrievals. This research underscores the practical difficulties in applying non-spherical phase function into the satellite retrieval algorithms because current remote sensing retrievals cannot determine the ratios between spherical and non-spherical particles. Further studies are also needed on how to better quantify aerosol morphologies and thus better model the phase function of irregular sharp-edge particles.
DE: 0300 ATMOSPHERIC COMPOSITION AND STRUCTURE
DE: 3359 Radiative processes
DE: 3360 Remote sensing
DE: 4801 Aerosols (0305)
SC: Atmospheric Sciences [A]
MN: 2003 Fall Meeting