Encyclopedia of Complexity and Systems Science

Living Edition
| Editors: Robert A. Meyers

Fluid Dynamics in Clouds

The Sum of Its Parts
Living reference work entry
DOI: https://doi.org/10.1007/978-3-642-27737-5_741-1

This entry is aimed at describing cloud physics with an emphasis on fluid dynamics. As is inevitable for a review of an enormously complicated problem, it is highly selective and reflects of the authors’ focus. The range of scales involved and the relevant physics at each scale are described.

Particular attention is given to droplet dynamics and growth, and turbulence with and without thermodynamics.



Tiny (∼0.1–1 μ) solid particles suspended in the air. There are about 100–1000 aerosol particles per cubic centimeter of air.


Mixtures of air (∼99% by weight), water vapor (1%), liquid water droplets (0.1%), aerosol particles, trace gases. Clouds are usually in turbulent flow.


Regions of the flow where particles with different velocities arrive simultaneously at the same location.


A system that has more water vapor than the saturation value prescribed by the Clausius-Clapeyron equation 5.

Ventilation effects:

The effects of oncoming flow...

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SR was supported under Swedish Research Council Grant No. 638-2013-9243.

JRP acknowledges funding from the IITB-IRCC seed grant.

SSR acknowledges DST (India) project MTR/2019/001553 for support.

RG and SSR acknowledge the support of the DAE, Govt. of India, under project no. 12-R\&D-TFR-5.10-1100.


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Authors and Affiliations

  1. 1.NorditaKTH Royal Institute of Technology and Stockholm UniversityStockholmSweden
  2. 2.Department of Chemical EngineeringIndian Institute of Technology BombayMumbaiIndia
  3. 3.International Centre for Theoretical SciencesTata Institute of Fundamental ResearchBangaloreIndia