Cascade: Investigating Multiscale Tropical Convective Organization Using High-Resolution Numerical Simulations Over Large Domains.

The Cascade project, a NERC-funded collaborative effort among several universities and research organizations in the UK, seeks to understand the organization and interaction of tropical convection at many scales, from individual convective plumes to mesoscale clusters, easterly waves, and the Madden-Julian Oscillation (MJO). High-resolution (up to 1-km grid length) simulations of the non-hydrostatic UK Met Office Unified Model (UM) are used over domains several thousand km across. One area of focus is African easterly waves in combination with the African Monsoon Multidisciplinary Analyses (AMMA) project. The Indo-Pacific warm pool is another main focus, and equatorial channel experiments over this domain will allow for detailed investigation of possible mechanisms leading to the MJO and other large-scale convective organization. Preliminary results for a test case of an active MJO event in the warm pool are shown, with the hope that modeling and analysis methods developed for this case can be applied to a similar event studied as part of the Year of Tropical Convection (YOTC).