Multicloud parametrizations for convectively coupled tropical waves

Recent observational analysis reveals the central role of three cloud types, congestus, stratiform, and deep convective cumulus clouds, in the dynamics of large scale convectively coupled Kelvin waves, westward propagating two-day waves, and the Madden-Julian oscillation (MJO). We present a systematic model convective parametrization highlighting the dynamic role of the three cloud types through two baroclinic modes of vertical structure: a deep convective heating mode and a second mode with low level heating and cooling corresponding respectively to congestus and stratiform clouds. Numerical results with an imposed SST gradient leading to a climatology consisting of a Gill's model-like Walker and Hadley circulations and wave fluctuations on the form of convectively coupled Kelvin wave packets with an MJO like dynamical structure are presented.