A PDF-Based Model for Boundary Layer Clouds. Part I: Method and Model Description

A new cloudy boundary layer single-column model is presented. It is designed to be flexible enough to represent a variety of cloudiness regimes-such as cumulus, stratocumulus, and clear regimes-without the need for case-specific adjustments. The methodology behind the model is the so-called assumed probability density function (PDF) method. The parameterization differs from higher-order closure or mass-flux schemes in that it achieves closure by the use of a relatively sophisticated joint PDF of vertical velocity, temperature, and moisture. A family of PDFs is chosen that is flexible enough to represent various cloudiness regimes. A double Gaussian family proposed by previous works is used. Predictive…

• NS
  National Science Foundation

  Award: 9529321
• NO
  National Oceanic and Atmospheric Administration