HR: 11:35h
AN: A21G-05    [PDF]
TI: New Techniques For Predicting Optical Properties Of Nonspherical Multicomponent Aerosols Using Single Particle Measurements
AU: * Sokolik, I N
EM: isokolik@eas.gatech.edu
AF: School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA 30332-0340 United States
AU: Anderson, J R
EM: janderson@asu.edu
AF: Arizona State University, P.O. Box 876106, Tempe, AZ 85287 United States
AU: Guazzotti, S A
EM: serad@chem.ucsd.edu
AF: Department of Chemistry and Biochemistry, University of California, La Jolla, CA 92093 United States
AU: Prather, K A
EM: kprather@chem.ucsd.edu
AF: Department of Chemistry and Biochemistry, University of California, La Jolla, CA 92093 United States
AB: Better understanding of diverse effects of atmospheric aerosols on climate and atmospheric chemistry requires more realistic treatments of physical and chemical properties of aerosol particles. Recent measurements demonstrate that a large fraction of aerosol particles has complex chemical composition and exhibits a variety of shapes. This paper presents new techniques for predicting the optical properties of nonspherical multicomponent aerosols containing mineral dust and/or black carbon. The strategy is to incorporate the statistical information on size-resolved composition and morphology of individual aerosol particles to predict the probability distribution of their main optical characteristics. The techniques were applied to the data provided by the aerosol time-of-flight mass spectroscopy and electronic microscopy. The predicted optical models were then used in calculations of the radiative impact of aerosols under different atmospheric conditions. Similar radiative transfer calculations were performed using a standard approach, by applying Mie theory to an ensample of spherical particles with a log-normal particle size distribution and effective refractive indices. We will address the differences in the radiative effects predicted with both approaches. Also the advantage/disadvantage of both methods will be discussed.
DE: 0305 Aerosols and particles (0345, 4801)
DE: 0394 Instruments and techniques
DE: 0649 Optics
DE: 3359 Radiative processes
SC: Atmospheric Sciences [A]
MN: 2003 Fall Meeting