Modeling of backscattering by non-spherical ice particles for the interpretation of cloud radar signals at 94 GHz. An error analysis

H. Okamoto, A. Macke, M. Quante, E. Raschke

Research output: Contribution to journalArticle

27 Citations (Scopus)

Abstract

Backsacttering by non-spherical ice particles at 94 GHz (3.2 mm wavelength) has been examined for hexagonal cylinders with aspect ratios ranging from 0.2 to 10, ie from plate-like to needle-like particles, as well as for combinations of hexagonal columns. Calculations have been performed using the Discrete Dipole Approximation (DDA). The results are of particular interest for the recently available 94 GHz cloud radar systems. In order to estimate the required number of dipoles to model a given particle, two empirical criteria have been formulated, which take into account the size and the non-sphericity of the particle. The origins of errors in the DDA method have been investigated. The effects of neglecting higher orders of multipole terms are much smaller than the errors due to the approximation of the particle shaping by arranging dipoles on a cubic array. The backscattering properties of horizontally oriented ice particles have been calculated. Both the backscattered radiance and the depolarization ratio strongly depend on the particle size and aspect ratio. -Authors

Original languageEnglish
Pages (from-to)319-334
Number of pages16
JournalContributions to Atmospheric Physics
Volume68
Issue number4
Publication statusPublished - Jan 1 1995

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error analysis
radar
backscattering
ice
modeling
dipoles
aspect ratio
approximation
radiance
particle
needles
depolarization
multipoles
particle size
wavelength
estimates
wavelengths

All Science Journal Classification (ASJC) codes

  • Physics and Astronomy(all)
  • Earth and Planetary Sciences(all)

Cite this

Modeling of backscattering by non-spherical ice particles for the interpretation of cloud radar signals at 94 GHz. An error analysis. / Okamoto, H.; Macke, A.; Quante, M.; Raschke, E.

In: Contributions to Atmospheric Physics, Vol. 68, No. 4, 01.01.1995, p. 319-334.

Research output: Contribution to journalArticle

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