Stratosphere-troposphere Interactions

将研究环形模态在气候变率动力学中的作用，特别侧重于（i）平流层结构和环流变化影响对流层纬向气流从而影响地面气候的动力学机制，（ii）对流层和平流层涡动反馈过程在这种相互作用的动力学中的作用，以及（iii）波动耗散定理对于理解纬向流对外部扰动的响应的适用性。虽然这项调查是部分理论分析，大部分的研究将包括一个简化的平流层-对流层大气环流模式的实验套件。未来的实验将包括表面地形，以确保平流层Rossby波活动的现实水平，以及模型气候中的非地带性的现实程度。这些研究将进一步了解大气环模，并确定可能提供足够耦合的过程，导致平流层对对流层的重大影响。这项研究的更广泛影响是对气候建模的实践：如果正确建模平流层是建模地表气候的重要先决条件，那么对气候模型就有重要的影响。此外，这项工作将对理解人为扰动的动态影响，特别是温室气体增加和臭氧消耗对气候的动态影响产生影响。

The role of annular modes in the dynamics of climate variability will be investigated, focusing especially on (i) the dynamical mechanisms by which changes in the structure and circulation of the stratosphere can affect the tropospheric zonal flow, and thence surface climate, (ii) the role that tropospheric and stratospheric eddy feedback processes play in the dynamics of this interaction, and (iii) the applicability of the fluctuation-dissipation theorem to the understanding of the response of the zonal flow to external perturbations. While this investigation is part theoretical analysis, the bulk of the research will comprise suites of experiments in a simplified stratosphere-troposphere general circulation model. Future experiments will include surface topography, in order to ensure a realistic level of stratospheric Rossby wave activity, as well as a realistic degree of non-zonality in the model climate. These studies will further understanding of atmospheric annular modes, and identify the processes that may provide sufficient coupling to lead to significant stratospheric influences on the troposphere. Broader impacts of this research are for the practice of climate modeling: if modeling the stratosphere correctly is an important prerequisite to modeling surface climate, there are important implications for climate models. Further, this work will have implications for the understanding of the dynamical impact of imposed perturbations, especially of increasing greenhouse gases and ozone depletion on climate.