Differentiating Cyclogenesis with and without Large Amplitude Mesoscale Gravity Waves: Implications for Rapidly Varying Heavy Precipitation and Gusty Winds

大气重力波指的是由于初始位移而上升和下沉的空气，然后向外传播，就像池塘上的涟漪一样。虽然大气重力波通常是由山区地形或飓风和雷暴产生的，但它们也可以在发展中的低压系统中形成，例如大暴风雪。重力波增强的上升运动可以导致更强的降水和风，使它们与社会极其相关。然而，并非所有发展中的系统都包含引力波。这个研究项目将利用数值模拟和有重力波和没有重力波的风暴观测，研究重力波在气旋形成过程中的原因。这项工作的潜在结果是提高预测重力波及其产生的高影响天气的能力。该项目将包括两名研究生，从而培养下一代科学家。这个项目将评估快速发展的中纬度气旋及其与重力波产生的关系。研究小组认为，预测气旋形成和气旋演变过程中的重力波需要多尺度理论来将动力演变与其前驱环境分开。气旋形成的演变将与重力波的发生、放大和维持进行相互比较，目的是建立一个可靠地区分重力波耦合气旋与非重力波气旋的理论。要验证的具体假设是，对于大振幅重力波的气旋形成，对流层中上层等熵位涡的相位更集中在地转和总风极大值分离较宽的不平衡射流出口区流、对流层中上层暖锋和非绝热加热之间。为了解决这一假设，将采用基于案例研究的数值模拟方法，在1公里嵌套配置中使用WRF-ARW模型。建模工作将包括全物理模拟，根据观测结果进行验证，并进行额外的模拟，以评估不同物理方案和初始条件的影响。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Atmospheric gravity waves refer to air that rises and sinks due to an initial displacement and then propagates outward, like a ripple on a pond. While atmospheric gravity waves are commonly generated by mountainous terrain or hurricanes and thunderstorms, they can also form within developing low pressure systems, such as large snowstorms. The enhanced rising motion from the gravity waves can contribute to more intense precipitation and wind, making them extremely relevant to society. However, not all developing systems contain gravity waves. This research project will investigate the causes of gravity waves in developing cyclones using numerical modeling and observations of storms with and without gravity waves. The potential outcome of this work is an improved ability to forecast gravity waves and the resultant high-impact weather that they produce. The project will include two graduate students, thereby training the next generation of scientists.This project will assess rapidly developing mid-latitude cyclones and their relationship to gravity wave production. The research team theorizes that predicting gravity waves during cyclogenesis and cyclone evolution requires a multi-scale theory to separate the dynamical evolution from their precursor environments. The evolution of cyclone formation will be inter-compared with gravity wave genesis, amplification, and maintenance with the goal to create a theory that reliably separates gravity wave-coupled cyclone cases from non-gravity wave cyclones. The specific hypothesis that will be tested is that for cyclogenesis with large amplitude gravity waves, the phasing of the mid-upper tropospheric isentropic potential vorticity is more focused among the unbalanced jet exit region flow with wide separation between the geostrophic and total wind maxima, mid-upper tropospheric warm front, and diabatic heating. To address this hypothesis, a case study-based numerical modeling approach would be undertaken, using the WRF-ARW model in a 1km nested configuration. The modeling work will consist of full-physics simulations, with validation against observations and additional simulations to assess the impacts of different physics schemes and initial conditions.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.