RUI: Dynamical Coupling during Major Stratospheric Sudden Warming

以北方半球冬季极涡的突然崩溃为特征的平流层突然变暖（SSW）可引起中间层的显著和意想不到的变化，最近80公里处平流层顶升高的证据强调了这一点。平流层和中间层之间的联系可能与重力波（GW）和行星波（PW）有关，这是时空谱两端的动力学特征。在此背景下，本项目试图阐明与主要SSW相关的平流层-中间层耦合，方法是（1）表征平流层和中间层中GW和PW的来源/特性，以及（2）评估它们在驱动这种耦合和升高的平流层顶中的作用和相互作用。它将采用三管齐下的多尺度方法，基于国家大气研究中心（NCAR）的全大气社区气候模型（WACCM），俄克拉荷马州大学的高级区域预测系统（ARPS）和观测。使用WACCM，将检查解决行星尺度和参数化GW强迫沿着波引起的环流，增强示踪剂传输到平流层和影响地面气候。由于空间分辨率高，ARPS模拟将明确解决大部分GW活动，直到较低的中间层。通过ARPS，阐明GW属性将有助于澄清它们的来源和强迫在WACCM中看到。最后，将对卫星观测和分析产品（包括推断和参数化的GW影响）进行检查，并与模型结果进行比较。这项工作的广泛影响是多方面的。在过去的十年中，主要SSW的检查主要集中在其对对流层的潜在影响。通过扩大现有的观点，包括中间层和GWs的细节，新的见解SSW演变可以通过这个项目获得。此外，相关项目活动旨在丰富课堂内外的本科教育。参与的本科生将进行实验，分析模型和观测数据，并提出研究结果。最后，该项目提供本科研究培训和接触尖端的地球物理研究，（1）可能无法在类似的国家支持的文科院校，（2）是独一无二的南卡罗来纳州和更大的东南地区。

Characterized by an abrupt break-down of the Northern Hemisphere winter polar vortex, a major stratospheric sudden warming (SSW) can elicit notable and unexpected changes in the mesosphere, as underlined by recent evidence of an elevated stratopause at 80 km. The connection between the stratosphere and mesosphere is potentially tied to gravity waves (GWs) and planetary waves (PWs), dynamical features on the opposite ends of the spatiotemporal spectrum. Given this background, this project seeks to illuminate the stratosphere-mesosphere coupling with respect to major SSWs by (1) characterizing the sources/properties of GWs and PWs in the stratosphere and mesosphere, and by (2) assessing their roles and interactions in driving this coupling and the elevated stratopause. It will employ a three pronged, multiple-scaled approach, based on the National Center for Atmospheric Research (NCAR) Whole Atmosphere Community Climate Model (WACCM), the University of Oklahoma's Advanced Regional Prediction System (ARPS), and observations. Using WACCM, resolved planetary-scale and parameterized GW forcings will be examined along with the wave-induced circulation that enhances tracer transport into the stratosphere and influences surface climate. With high spatial resolution, the ARPS simulations will explicitly resolve much of the GW activities up to the lower mesosphere. Through ARPS, the elucidated GW properties will help clarify their sources and forcings seen in WACCM. Finally, satellite observations and analysis products (with inferred and parameterized GW influence) will be examined and compared to model results. The broader impacts of this work are multifold. In the past decade, examinations of major SSWs have focused predominantly on their potential impacts on the troposphere. By broadening the current views to include the mesosphere and details of GWs, new insights on SSW evolution can be obtained through this project. Additionally, related project activities aim to enrich undergraduate education inside and outside the classroom. Participating undergraduates will conduct experiments, analyze model and observational data, and present research results. Finally, the project offers undergraduate research training and exposure to cutting-edge geophysical research that (1) may not otherwise be available at similar state-supported Liberal Arts institutions and that (2) is unique in South Carolina and the greater Southeastern Region.