The Madden-Julian oscillation is a prime example of the multiscale organization of atmospheric convection. In particular, the effects of small spatial scales and high-frequency temporal scales attendant to deep precipitating convection are fundamental to the large-scale low-frequency dynamics of the tropics -- and vice versa, meaning that both upscale and downscale dynamical influences are at work. But these influences are understood incompletely and poorly represented in contemporary large-scale models. In part, this arises because contemporary convective parameterizations do not properly represent the dynamical processes that accompany convective organization.

Idealized analytic models of convective organization can quantify the mechanisms involved with the above aspects in a quantitive, precise and reductionist manner. Cloud-system-resolving models (CSRM) that resolve mesoscale dynamics, represent the complexity of convective organization and its interaction with small-scale parameterized processes with more precision and across a wider dynamic range than possible using contemporary global models. Analytic models and CSRMs are a particularly powerful combination.

This talk will focus on analytic model and CSRM results pertinent to organized precipitating convection and its scale interactions in the tropics. The transport of zonal momentum in the vertical and meridional directions and the generation of atmospheric super-rotation are selected for study since these are fundamental to the large-scale circulation of the tropical atmosphere and its variability.