An accurate representation (parameterization) of deep convective clouds is essential for the successful simulation of precipitation in climate models. However, the question of closure (i.e., how to find a closed system of equations) for convective parameterizations remains unsettled. Because the parameterization is conceptually a description of an ensemble of convective clouds, the development of “statistical cumulus dynamics” (SCD) would be the ultimate way to provide the closure, just as the statistical mechanics of a microphysical system provides the ultimate basis for its macrophysical thermodynamics.
The concept of SCD was introduced by A. Arakawa and W. H. Schubert (J. Atmos. Sci., 31, 674–701, 1974) in their seminal work on mass-flux convective parameterization. Although progress since then has been slow, some pioneering work has recently been done in Europe. A workshop was organized at the Max Planck Institute for Meteorology for intensive discussions of SCD.