RUI: Gravity Waves and the Stratospheric Polar Vortex

重力波在低层大气和平流层之间提供了重要的耦合。强烈的冬季天气扰动显著增强了急流的曲率，促进了地形上的适当流动，从而激发了传播到平流层的强重力波，在平流层中它们可以改变极地涡旋的强度。由重力波引起的热扰动可以触发平流层下层的极地平流层云的形成——这种云参与了臭氧的催化破坏。该项目将描述极地冬季重力波的来源和特性及其向平流层的传播，并将评估重力波与极地环流之间的相互作用。重力波事件直至平流层顶的数值模拟将使用为本研究修改的高分辨率天气预报模型进行。模拟重力波将与卫星观测结果进行比较，这将有助于对重力波的特性、来源和传播进行表征和改进理解。将估计重力波对极地涡旋的影响，并探讨重力波在极地平流层云形成中的作用。这些研究将有助于限制如何将重力波效应纳入全球气候模式，从而提高这些模式评估气候演变和臭氧变率的有效性。在本科院校研究（RUI）项目下开展的活动将丰富课堂内外的本科教育。新获得的项目成果和模型实验将纳入课程。本科生研究人员将与合作科学家合作，进行建模实验，分析模型输出和观测数据，并展示研究成果。在这样做的过程中，他们将参与前沿的地球物理研究，这在类似的国家支持的文科院校通常是不可用的，这在该地区将是独一无二的。

Gravity waves provide important coupling between the lower atmosphere and the stratosphere. Intense wintertime synoptic disturbances that significantly enhance the jet stream curvature and promote suitable flow over topography can excite strong gravity waves that propagate into the stratosphere, where they can modify the strength of the polar vortex. Thermal perturbations induced by gravity waves can trigger the formation of polar stratospheric clouds in the lower stratosphere - such clouds participate in the catalytic destruction of ozone. This project will characterize the sources and properties of wintertime gravity waves in the polar regions and their propagation into the stratosphere and will assess the interactions between gravity waves and the polar circulation. Numerical simulations of gravity-wave events up to the stratopause will be performed using a high-resolution weather forecasting model that has been modified for this study. Simulated gravity waves will be compared with satellite observations will allow the characterization and improved understanding of wave properties, sources and propagation. Gravity-wave influences on the polar vortex will be estimated and the roles of gravity waves in the formation of polar stratospheric clouds will be explored.These studies will help constrain how gravity-wave effects can be incorporated into global climate models, thereby improving the effectiveness of these models for assessing climate evolution and ozone variability. Activities carried out under this Research at an Undergraduate Institution (RUI) project will enrich undergraduate education inside and outside the classroom. Newly obtained project results and model experiments will be incorporated into courses. Undergraduate researchers will work with collaborating scientists, conduct modeling experiments, analyze model output and observational data, and present research results. In so doing, they will participate in cutting-edge geophysical research that is generally unavailable at similar state-supported liberal arts institutions and that will be unique within the region.