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arXiv · 0801.1618

The fall speeds of sub-100 micron ice crystals

C. D. Westbrook
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Abstract

Estimates for the sedimentation rate of realistic ice crystals at sizes smaller than 100 $μ$m are presented. These calculations, which exploit new results for the capacitance of ice crystals, are compared with laboratory studies and found to be in good agreement. The results highlight a weakness in contemporary ice particle fall speed parameterisations for very small crystals, which can lead to sedimentation rates being overestimated by a factor of two. The theoretical approach applied here may also be useful for calculating the sedimentation rate and mobility of non-spherical aerosol particles.

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C. D. Westbrook. 2008-12-06. The fall speeds of sub-100 micron ice crystals. https://doi.org/10.1002/qj.290

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