Multiscale Coherent Structure Parameterization for Organized Moist Convection

Lagrangian-based nonlinear dynamical models developed by the author are utilized for a new multiscale coherent structure parameterization (MCSP) for organized moist convection. In “gray-zone” nomenclature, sub-grid convection is treated by traditional cumulus parameterization and the dynamical models approximate organized transport. Note that the intent is not to replace cumulus parameterizations but to add the extensively observed process of organized convection that is missing from traditional global climate models. The dynamical models approximate cloud-system resolving simulations of convective organization in the April 2009 MJO in the Year of Tropical Convection (YOTC) virtual global field-campaign. Tropical squall-lines, mesoscale convective systems, superclusters and equatorial waves are shown to have  self-similar structure and the dynamical models  approximate their key heat and momentum transport properties. The MCSP paradigm will be introduced and the sensitivity of the large-scale atmospheric circulation to MCSP in the Community Atmosphere Model (CAM 6) described.