Halos and ice crystals
نویسندگان
چکیده
Observing cirrus halos to constrain in-situ measurements of ice crystal size T. J. Garrett, M. B. Kimball, G. G. Mace, and D. G. Baumgardner Department of Meteorology, University of Utah, Salt Lake City, UT, 84112-0110, USA Universidad Nacional Autonoma de Mexico, Mexico City, Mexico Received: 21 December 2006 – Accepted: 16 January 2007 – Published: 26 January 2007 Correspondence to: T. Garrett ([email protected])
منابع مشابه
A note on the radiance distributions of halos due to scattering by randomly orientated crystals.
The radiance distribution of light scattered by randomly oriented ice crystals differs fundamentally from the radiance distribution of light scattered by spherical raindrops or by preferentially oriented ice crystals. A formalism for light scattering by randomly oriented crystals is given and applied to four examples, among them the circular 22° halo and the antisolar halospot, the latter being...
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In this study, characteristic optical sizes of ice crystals in synoptic cirrus are determined using airborne measurements of ice crystal size distributions, optical extinction and water content. The measurements are compared with coincident visual observations of ice cloud optical phenomena, in particular the 22◦ and 46◦ halos. In general, the 5 scattering profiles derived from the in-situ clou...
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Phase functions have been calculated using the Monte Carlo/geometric ray tracing method for single hexagonal pyramidal ice crystals (such as solid and hollow bullets) randomly oriented in space and horizontal plane, in order to study the concentric halo formations. Results from three dimensional model calculations show that 9° halo can be as bright as the common 22° halo for pyramidal angle of ...
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