Scattering matrix of infrared radiation by ice finite circular cylinders
Abstract
Scattering matrix characteristics of polydisperse, randomly oriented, small ice crystals modeled by finite circular cylinders with various ratios of the length to diameter (L /D) ratio are calculated by use of the exact T matrix approach, with emphasis on the thermal infrared spectral region that extends from the atmospheric shortwave IR window to the farIR wavelengths to as large as 30 μm. The observed ice crystal size distribution and the wellknown powerlaw distribution are considered. The results of the extensive calculations show that the characteristics of scattering matrix elements of small ice circular cylinders depend strongly on wavelengths and refractive indices, particle size distributions, and the L /D ratios. The applicability of the powerlaw distribution and particle shapes for light scattering calculations for small ice crystals is discussed. The effects of the effective variance of size distribution on light scattering characteristics are addressed. It seems from the behavior of scattering matrix elements of small ice crystals that the combination of 25 and 3.979 μm has some advantages and potential applications for remote sensing of cirrus and other ice clouds.
 Publication:

Applied Optics
 Pub Date:
 April 2002
 DOI:
 10.1364/AO.41.002333
 Bibcode:
 2002ApOpt..41.2333X
 Keywords:

 Angles (Geometry);
 Atmospheric Optics;
 Atmospheric Windows;
 Circular Cylinders;
 Clouds;
 Far Infrared Radiation;
 Ice;
 Infrared Radiation;
 Infrared Spectra;
 Infrared Windows;
 Light Scattering;
 Matrices (Mathematics);
 S Matrix Theory;
 Spectral Bands;
 Optics