Estimation of the Asymmetry Parameter from microphysical observations
نویسنده
چکیده
A new method of calculating the asymmetry parameter from aircraft microphysical observations is discussed and has been applied to aircraft data where direct measurements are available. Recent parameterizations of the asymmetry parameter often are based on theoretical ray-tracing results for simple particle shapes. One recent theory, which has gained prominence, is the use of equivalent surface volume/area spheres to estimate the scattering properties of ice particles. In this paper a new technique is described for determining the properties necessary for calculation of appropriate equivalent spheres. These calculations have been applied to aircraft in-situ data from the Cirrus Regional Study of Tropical Anvils and Cirrus Layers Florida Area Cirrus Experiment (CRYSTAL-FACE) mission. The results were in poor agreement with direct asymmetry parameter measurements. Considering the near field interactions of radiation within a cluster of spheres as opposed to considering each sphere individually is not likely to improve the agreement.
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