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

该项目将调查罗斯贝波在副热带对流层上层的破裂及其对大气环流的影响。 波浪破碎发生在波浪振幅变大时，并导致位涡混合。 在波浪破碎区域的非线性动力学过程，包括潜在的反射波能量向源区域，没有得到很好的理解。 这些过程在北方温带冬季产生季节内变化中的作用也不清楚。 Magnusdottir博士（加州大学欧文分校）将使用简单的理论模型和一套日益复杂的数值模型来研究所涉及的动力学过程。 她将分析季节性周期和大陆性对波能非线性反射的影响，并在观测中寻找反射的证据。 动力过程的分析，导致，并产生于，罗斯贝波在上亚热带地区的破碎，应导致更好的理解和模拟热带-热带外的相互作用和大气环流。

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.