title: Scattering of solar radiation by hexagonal ice crystals.
abstract: The classical ray optics approximation has been applied to compute the angular scattering of light by finitesized hexagonal ice crystals in the form of columns and plates. The results are presented at a wavelength of 0.55 microm for a random orientation of the crystals either in space or in a plane. The results are also compared to those of ice spheres. For the first time the angular light scattering of platelike crystals and a quantitative description of the 46 degrees halo are given. Contrary to earlier studies, it is shown that both plate- and columnlike ice crystals show a strong backscattering. In agreement with previous studies, ice spheres are found to scatter-when compared to ice prisms-less energy at angles near 90 degrees . With regard to the effect of orientation on the light scattering, it is shown that columnlike crystals randomly oriented in a plane behave rather like spherical particles and not like columns randomly oriented in space.
authors.forename: P
authors.initials: P
authors.lastname: Wendling
authors.forename: R
authors.initials: R
authors.lastname: Wendling
authors.forename: H K
authors.initials: HK
authors.lastname: Weickmann