pure and applied geophysics

, Volume 113, Issue 1, pp 1067–1084 | Cite as

Turbulence, entrainment, and mixing in cloud dynamics

  • James W. Telford


The various models that have been proposed for describing the dynamical development of small cumuli are discussed in terms of how well they predict the observed distribution of liquid water. The entrainment concept is examined and shown to involve contradictions when applied to growing blobs. An alternative process is offered in which the dominating factor in the cloud dynamics is the mixing in of drier overlying air down through the cloud until temporary static equilibrium is established. Consideration of the mixing process and calculations of the required dilution show this process can lead to the observed liquid water distributions.


Static Equilibrium Liquid Water Dynamical Development Water Distribution Alternative Process 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. R. R. Braham andP. Squires (1974),Cloud physics—1974, Bull. of the Am. Met. Soc.55, 543–586.Google Scholar
  2. J. W. Deardorff (1972),Numerical investigation of neutral and unstable planetary boundary, J. Atmos. Sci.29, 91–115.Google Scholar
  3. G. D. Fox (1972),Numerical simulation of three-dimensional shape-preserving convective elements, J. Atmos. Sci.29, 322–341.Google Scholar
  4. H. Lamb Hydrodynamics (Cambridge University Press 1932).Google Scholar
  5. B. R. Morton, G. Taylor, andJ. S. Turner (1956),Turbulent gravitational convection from maintained and instantaneous sources, Proc. Roy. Soc. London, Ser. A234, 1–23.Google Scholar
  6. H. D. Orville andL. J. Sloan (1970),A numerical simulation of the life history of a rainstorm, J. Atmos. Sci.27, 1148–1159.Google Scholar
  7. J. M. Richards (1961),Experiments on the penetration of an interface by buoyant thermals, J. Fluid Mech.11, 369–384.Google Scholar
  8. R. S. Scorer andC. Ronne (1956),Experiments with convection bubbles, Weather11, 151–154.Google Scholar
  9. J. Simpson (1971),On cumulus entrainment and one dimensional models, J. Atmos. Sci.28, 449–455.Google Scholar
  10. J. Simpson (1972)Reply (to Warner), J. Atmos. Sci.29, 220–225.Google Scholar
  11. P. Squires (1958-A),The spatial variation of liquid water and droplet concentration in cumuli, Tellus10, 372–379.Google Scholar
  12. P. Squires (1958-B),Penetrative downdraughts in cumuli, Tellus10, 381–389.Google Scholar
  13. H. Stommel (1947),Entrainment of air into a cumulus cloud, J. Meteor.4, 91–94.Google Scholar
  14. J. W. Telford (1966),The convective mechanism in clear air, J. Atmos. Sci.23, 652–666.Google Scholar
  15. J. W. Telford (1970),Convective plumes in a convective field, J. Atmos. Sci.27, 347–358.Google Scholar
  16. J. W. Telford (1972),A plume theory for the convective field in clear air, J. Atmos. Sci.29, 128–134.Google Scholar
  17. J. W. Telford (1975),The effects of compressibility and dissipation heating on boundary layer plumes, J. Atmos. Sci.32, 108–115.Google Scholar
  18. J. W. Telford andP. B. Wagner (1974),The measurement of horizontal air motion near clouds from aircraft, J. Atmos. Sci.31, 2066–2080.Google Scholar
  19. J. S. Turner (1963),Model experiments relating to thermals with increasing buoyancy, Q. J. R. met. Soc.89, 62–74.Google Scholar
  20. J. S. Turner (1964),The flow into an expanding spherical vortex, J. Fluid Mech.18, 195–208.Google Scholar
  21. J. Warner (1955),The water content of cumuliform cloud, Tellus7, 449–457.Google Scholar
  22. J. Warner (1970),On steady-state one-dimensional models of cumulus convection, J. Atmos. Sci.27, 1035–1040.Google Scholar
  23. J. Warner (1972),Comments ‘On cumulus entrainment and one dimensional models,’ J. Atmos. Sci.29, 218–219.Google Scholar

Copyright information

© Birkhäuser Verlag 1975

Authors and Affiliations

  • James W. Telford
    • 1
  1. 1.Laboratory of Atmospheric Physics, Desert Research InstituteUniversity of Nevada SystemRenoUSA

Personalised recommendations