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Universality in snowflake aggregation

C. D. Westbrook·R. C. Ball·P. R. Field·A. J. Heymsfield
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Abstract

Aggregation of ice crystals is a key process governing precipitation. Individual ice crystals exhibit considerable diversity of shape, and a wide range of physical processes could influence their aggregation; despite this we show that a simple computer model captures key features of aggregate shape and size distribution reported recently from Cirrus clouds. The results prompt a new way to plot the experimental size distributions leading to remarkably good dynamical scaling. That scaling independently confirms that there is a single dominant aggregation mechanism at play, albeit our model (based on undeflected trajectories to contact) does not capture its form exactly.

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C. D. Westbrook, R. C. Ball, P. R. Field, A. J. Heymsfield. 2004-06-21. Universality in snowflake aggregation. https://doi.org/10.1029/2004gl020363

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