Hostname: page-component-7c8c6479df-r7xzm Total loading time: 0 Render date: 2024-03-28T17:05:07.661Z Has data issue: false hasContentIssue false

Cloud-top entrainment instability?

Published online by Cambridge University Press:  16 September 2010

B. STEVENS*
Affiliation:
Max-Planck-Institut für Meteorologie, Bundesstrasse 53, 20146 Hamburg, Germany
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Mixing processes at cloud boundaries are thought to play a critical role in determining cloud lifetime, spatial extent and cloud microphysical structure. High-fidelity direct numerical simulations by Mellado (J. Fluid Mech., 2010, this issue, vol. 660, pp. 5–36) show, for the first time, the character and potency of a curious instability that may arise as a result of molecular mixing processes at cloud boundaries, an instability which until now has been thought by many to control the distribution of climatologically important cloud regimes.

Type
Focus on Fluids
Copyright
Copyright © Cambridge University Press 2010

References

Bony, S. & Dufresne, J.-L. 2006 Marine boundary layer clouds at the heart of tropical cloud feedback uncertainties in climate models. Geophys. Res. Lett. 32, L20806.Google Scholar
Bretherton, C. S. 1987 A theory for nonprecipitating moist convection between two parallel plates. Part I. Thermodynamics and linear solutions. J. Atmos. Sci. 44, 18091827.2.0.CO;2>CrossRefGoogle Scholar
Deardorff, J. W. 1980 Cloud top entrainment instability. J. Atmos. Sci. 37, 131147.2.0.CO;2>CrossRefGoogle Scholar
Kuo, H.-C. & Schubert, W. H. 1988 Stability of cloud-topped boundary layers. Q. J. R. Meteor. Soc. 114, 887916.Google Scholar
Mellado, J. P. 2010 The evaporatively-driven cloud-top mixing layer. J. Fluid. Mech. 660, 536.CrossRefGoogle Scholar
Mellado, J. P., Stevens, B., Schmidt, H. & Peters, N. 2009 Buoyancy reversal in cloud-top mixing layers. Q. J. R. Meteor. Soc. 135, 963978.CrossRefGoogle Scholar
Mellado, J. P., Stevens, B., Schmidt, H. & Peters, N. 2010 Two-fluid formulation of the cloud-top mixing layer for direct numerical simulation. Theor. Comput. Fluid Dyn. doi:10.1007/s00162-010-0182-x.CrossRefGoogle Scholar
Randall, D. A. 1980 Conditional instability of the first kind upside-down. J. Atmos. Sci. 37, 125130.2.0.CO;2>CrossRefGoogle Scholar
Stevens, B. 2005 Atmospheric moist convection. Annu. Rev. Earth Planet. Sci. 33, 605643.CrossRefGoogle Scholar
Stevens, B., Lenschow, D. H., Ian Faloona, C.-H. M., Lilly, D. K., Blomquist, B., Vali, G., Bandy, A., Campos, T., Gerber, H., Haimov, S., Morley, B. & Thorton, D. C. 2003 On entrainment in nocturnal marine stratocumulus. Q. J. R. Meteor. Soc. 129, 34693492.CrossRefGoogle Scholar