Author:
Shishko V. A.,Timofeev D. N.,Konoshonkin A. V.,Kustova N. V.,Kan N.,Tkachev I. V.,Masuda K.,Ishimoto H.,Okamoto H.,Borovoi A. G.
Abstract
Abstract
In this work, the problem of radiation scattering by ice crystals typical for cirrus clouds is solved for a 94-GHz radar (wavelength 3189 µm) and a lidar (wavelength 0.355 µm); the ice refractive indices are 1.7864 + 0.0032i and 1.3249 + 0i, respectively. The scattering matrices are calculated within the physical optics approximation and the discrete dipole approximation for the case of randomly oriented particles with sizes from 4 to 1000 µm. The ratio of the radar and lidar backscattering signals in the backward direction (the so-called radar–lidar ratio) is calculated for a wide range of the particle size for typical shapes of cirrus cloud ice crystals. It is shown that this ratio can be used for estimating the size of ice crystals in cirrus clouds.
Subject
Atmospheric Science,Earth-Surface Processes,Atomic and Molecular Physics, and Optics,Oceanography,Instrumentation,Pollution,Environmental Science (miscellaneous),Ecological Modeling
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