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arXiv · 1407.6392

Convective Ripening and Initiation of Rainfall

Michael Wilkinson
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Abstract

This paper discusses the evolution of the droplet size distribution for a liquid-in-gas aerosol contained in a Rayleigh-Bénard cell. It introduces a non-collisional model for broadening the droplet size distribution, termed 'convective ripening'. The paper also considers the initiation of rainfall from ice-free cumulus clouds. It is argued that while collisional mechanisms cannot explain the production of rain from clouds with water droplet diameters of $20\ μ{\rm m}$, the non-collisional convective ripening mechanism gives a much faster route to increasing the size of the small fraction of droplets that grow into raindrops.

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Michael Wilkinson. 2014-07-23. Convective Ripening and Initiation of Rainfall. https://doi.org/10.1209/0295-5075%2F108%2F49001

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