Nonlinear Dynamical Processes in the Subtropics and Tropics and Their Effects on the General Circulation

University Of California-Irvine, Irvine CA

Investigators

Abstract

The project will investigate the breaking of Rossby waves in the subtropical upper troposphere, and its consequences for the atmospheric general circulation. Wave breaking occurs when the wave amplitude becomes large, and results in mixing of potential vorticity. Nonlinear dynamical processes in the wave-breaking regions, including potential reflection of wave energy towards the source region, are not well understood. The role of these processes in generation of intra-seasonal-to-seasonal variability in the Northern extratropical winters is also unclear. Dr. Magnusdottir (UC Irvine) will study the involved dynamical processes using simple theoretical models and a suite of numerical models of increasing complexity. She will analyze the impact of the seasonal cycle and continentality on the nonlinear reflection of wave energy, and search for evidence of reflection in observations. The analysis of dynamical processes leading to, and resulting from, the breaking of Rossby waves in the upper subtropics should lead to improved understanding and modeling of tropical-extratropical interactions and the atmospheric general circulation.