• Albrecht, B. A., C. S. Bretherton, D. Johnson, W. H. Scubert, and A. S. Frisch, 1995: The Atlantic Stratocumulus Transition Experiment—ASTEX. Bull. Amer. Meteor. Soc., 76, 889904.

    • Search Google Scholar
    • Export Citation
  • Bretherton, C. S., P. N. Blossey, and C. R. Jones, 2013: Mechanisms of marine low cloud sensitivity to idealized climate perturbations: A single-LES exploration extending the CGILS cases. J. Adv. Model. Earth Syst.,5, 316–337, doi:10.1002/jame.20019.

  • Chung, D., G. Matheou, and J. Teixeira, 2012: Steady-state large-eddy simulations to study the stratocumulus to shallow cumulus cloud transition. J. Atmos. Sci., 69, 32643276.

    • Search Google Scholar
    • Export Citation
  • Deardorff, J. W., 1980: Cloud top entrainment instability. J. Atmos. Sci., 37, 131147.

  • Duynkerke, P. G., 1993: The stability of cloud top with regard to entrainment: Amendment of the theory of cloud-top entrainment instability. J. Atmos. Sci., 50, 495502.

    • Search Google Scholar
    • Export Citation
  • Heus, T., and Coauthors, 2010: Formulation of the Dutch Atmospheric Large-Eddy Simulation (DALES) and overview of its applications. Geosci. Model Dev., 3, 415444, doi:10.5194/gmd-3-415-2010.

    • Search Google Scholar
    • Export Citation
  • Klein, S. A., and D. L. Hartmann, 1993: The seasonal cycle of low stratiform clouds. J. Climate, 6, 15871606.

  • Kuo, H.-C., and W. H. Schubert, 1988: Stability of cloud-topped boundary layers. Quart. J. Roy. Meteor. Soc., 114, 887916, doi:10.1002/qj.49711448204.

    • Search Google Scholar
    • Export Citation
  • Lilly, D. K., 1968: Models of cloud-topped mixed layers under a strong inversion. Quart. J. Roy. Meteor. Soc., 94, 292309, doi:10.1002/qj.49709440106.

    • Search Google Scholar
    • Export Citation
  • Lock, A. P., 2009: Factors influencing cloud area at the capping inversion for shallow cumulus clouds. Quart. J. Roy. Meteor. Soc., 135, 941952, doi:10.1002/qj.424.

    • Search Google Scholar
    • Export Citation
  • MacVean, M. K., and P. J. Mason, 1990: Cloud-top entrainment instability through small-scale mixing and its parameterization in numerical models. J. Atmos. Sci., 47, 10121030.

    • Search Google Scholar
    • Export Citation
  • Mellado, J. P., B. Stevens, H. Schmidt, and N. Peters, 2009: Buoyancy reversal in cloud-top mixing layers. Quart. J. Roy. Meteor. Soc., 135, 963978, doi:10.1002/qj.417.

    • Search Google Scholar
    • Export Citation
  • Moeng, C.-H., 2000: Entrainment rate, cloud fraction, and liquid water path of PBL stratocumulus clouds. J. Atmos. Sci., 57, 36273643.

    • Search Google Scholar
    • Export Citation
  • Noda, A. T., K. Nakamura, T. Iwasaki, and M. Satoh, 2013: A numerical study of a stratocumulus-topped boundary-layer: Relations of decaying clouds with a stability parameter across inversion. J. Meteor. Soc. Japan,in press.

  • Park, S., C. B. Leovy, and M. A. Rozendaal, 2004: A new heuristic Lagrangian marine boundary layer cloud model. J. Atmos. Sci., 61, 30023024.

    • Search Google Scholar
    • Export Citation
  • Randall, D. A., 1980: Conditional instability of the first kind upside-down. J. Atmos. Sci., 37, 125130.

  • Randall, D. A., 1984: Stratocumulus cloud deepening through entrainment. Tellus, 36A, 446457, doi:10.1111/j.1600-0870.1984.tb00261.x.

    • Search Google Scholar
    • Export Citation
  • Sandu, I., and B. Stevens, 2011: On the factors modulating the stratocumulus to cumulus transitions. J. Atmos. Sci., 68, 18651881.

  • Siems, S. T., C. S. Bretherton, M. B. Baker, S. Shy, and R. E. Breidenthal, 1990: Buoyancy reversal and cloud-top entrainment instability. Quart. J. Roy. Meteor. Soc., 116, 705739, doi:10.1002/qj.49711649309.

    • Search Google Scholar
    • Export Citation
  • Stephens, G. L., 2005: Cloud feedbacks in the climate system: A critical review. J. Climate, 18, 237273.

  • Stevens, B., 2002: Entrainment in stratocumulus-topped mixed layers. Quart. J. Roy. Meteor. Soc., 128, 26632690, doi:10.1256/qj.01.202.

    • Search Google Scholar
    • Export Citation
  • Stevens, B., and Coauthors, 2003a: Dynamics and Chemistry of Marine Stratocumulus—DYCOMS-II. Bull. Amer. Meteor. Soc., 84, 579593.

  • Stevens, B., and Coauthors, 2003b: On entrainment rates in nocturnal marine stratocumulus. Quart. J. Roy. Meteor. Soc., 129, 34693493, doi:10.1256/qj.02.202.

    • Search Google Scholar
    • Export Citation
  • Stevens, B., and Coauthors, 2005: Evaluation of large-eddy simulations via observations of nocturnal marine stratocumulus. Mon. Wea. Rev., 133, 14431462.

    • Search Google Scholar
    • Export Citation
  • Stull, R., 1988: An Introduction to Boundary Layer Meteorology. Kluwer Academic, 666 pp.

  • Van der Dussen, J. J., and Coauthors, 2013: The GASS/EUCLIPSE model intercomparison of the stratocumulus transition as observed during ASTEX: LES results. J. Adv. Model. Earth Syst.,5, 483–499, doi:10.1002/jame.20033.

  • Wang, Q., and D. H. Lenschow, 1995: An observational study of the role of penetrating cumulus in a marine stratocumulus-topped boundary layer. J. Atmos. Sci., 52, 27782787.

    • Search Google Scholar
    • Export Citation
  • Wood, R., 2005: Drizzle in stratiform boundary layer clouds. Part I: Vertical and horizontal structure. J. Atmos. Sci., 62, 30113033.

    • Search Google Scholar
    • Export Citation
  • Wood, R., and C. S. Bretherton, 2004: Boundary layer depth, entrainment, and decoupling in the cloud-capped subtropical and tropical marine boundary layer. J. Climate, 17, 35763588.

    • Search Google Scholar
    • Export Citation
  • Xiao, H., C.-M. Wu, and C. R. Mechoso, 2011: Buoyancy reversal, decoupling and the transition from stratocumulus to shallow cumulus topped marine boundary layers. Climate Dyn., 37, 971984, doi:10.1007/s00382-010-0882-3.

    • Search Google Scholar
    • Export Citation
  • Yamaguchi, T., and D. A. Randall, 2008: Large-eddy simulation of evaporatively driven entrainment in cloud-topped mixed layers. J. Atmos. Sci., 65, 14811504.

    • Search Google Scholar
    • Export Citation
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Factors Controlling Rapid Stratocumulus Cloud Thinning

J. J. van der DussenDelft University of Technology, Delft, Netherlands

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S. R. de RoodeDelft University of Technology, Delft, Netherlands

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A. P. SiebesmaRoyal Netherlands Meteorological Institute, De Bilt, and Delft University of Technology, Delft, Netherlands

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Abstract

The relationship between the inversion stability and the liquid water path (LWP) tendency of a vertically well-mixed, adiabatic stratocumulus cloud layer is investigated in this study through the analysis of the budget equation for the LWP. The LWP budget is mainly determined by the turbulent fluxes of heat and moisture at the top and the base of the cloud layer, as well as by the source terms due to radiation and precipitation. Through substitution of the inversion stability parameter κ into the budget equation, it immediately follows that the LWP tendency will become negative for increasing values of κ due to the entrainment of increasingly dry air. Large κ values are therefore associated with strong cloud thinning. Using the steady-state solution for the LWP, an equilibrium value κeq is formulated, beyond which the stratocumulus cloud will thin. The Second Dynamics and Chemistry of Marine Stratocumulus field study (DYCOMS-II) is used to illustrate that, depending mainly on the magnitude of the moisture flux at cloud base, stratocumulus clouds can persist well within the buoyancy reversal regime.

Corresponding author address: Johan van der Dussen, Civil Engineering and Geosciences, Delft University of Technology, Stevinweg 1, Delft 2628 CN, Netherlands. E-mail: j.j.vanderdussen@tudelft.nl

Abstract

The relationship between the inversion stability and the liquid water path (LWP) tendency of a vertically well-mixed, adiabatic stratocumulus cloud layer is investigated in this study through the analysis of the budget equation for the LWP. The LWP budget is mainly determined by the turbulent fluxes of heat and moisture at the top and the base of the cloud layer, as well as by the source terms due to radiation and precipitation. Through substitution of the inversion stability parameter κ into the budget equation, it immediately follows that the LWP tendency will become negative for increasing values of κ due to the entrainment of increasingly dry air. Large κ values are therefore associated with strong cloud thinning. Using the steady-state solution for the LWP, an equilibrium value κeq is formulated, beyond which the stratocumulus cloud will thin. The Second Dynamics and Chemistry of Marine Stratocumulus field study (DYCOMS-II) is used to illustrate that, depending mainly on the magnitude of the moisture flux at cloud base, stratocumulus clouds can persist well within the buoyancy reversal regime.

Corresponding author address: Johan van der Dussen, Civil Engineering and Geosciences, Delft University of Technology, Stevinweg 1, Delft 2628 CN, Netherlands. E-mail: j.j.vanderdussen@tudelft.nl
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