Leslie Smith | Department of Mathematics, University of Wisconsin
Modeling Atmospheric Flows with Phase Changes of Water
Turbulent convection in the earth's atmosphere is characterized by phase changes of water and latent heat release. Moist convection may organize itself on multiple length and time scales, for example, the vortical hot towers responsible for heat transport in hurricanes (10 km wide), squall lines (200 km wide), and convectively coupled waves (2000 km scales). This work addresses the question: what is the minimal representation of water substance and (thermo)dynamics able to reproduce the basic regimes of turbulent convective organization? The limit of asymptotically fast cloud microphysics is explored numerically and theoretically, and used to derive a precipitating quasi-geostrophic description of large-scale flows, analogous to the dry quasi-geostrophic equations, which have been foundational for turbulence theory in the mid-latitude atmosphere.