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arXiv · 2601.00637

Turbulence is ineffective in causing raindrop growth in polluted clouds

K. Shri Vignesh·Ambedkar Sanket Sukdeo·P. V. Sruthibhai·Aishwarya Singh·Srikrishna Sahu·Swetaprovo Chaudhari·Amit K. Patra·T. Narayana Rao·Rama Govindarajan·Sachin S. Gunthe·R. I. Sujith
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Abstract

Aerosol-cloud interactions represent the largest uncertainty in climate-change assessment, and while cloud turbulence is considered crucial for droplet growth, its precise role remains unclear. Our laboratory-controlled studies show that turbulence does not always enhance collision and coalescence; instead, its influence emerges only when droplets have a sufficiently broad size distribution. The dissipative-scale droplet behaviour underscores the importance of improved parameterisations to accurately model cloud microphysics.

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K. Shri Vignesh, Ambedkar Sanket Sukdeo, P. V. Sruthibhai, Aishwarya Singh, Srikrishna Sahu, Swetaprovo Chaudhari, Amit K. Patra, T. Narayana Rao, Rama Govindarajan, Sachin S. Gunthe, R. I. Sujith. 2026-01-02. Turbulence is ineffective in causing raindrop growth in polluted clouds. https://arxiv.org/abs/2601.00637

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