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

区分有和没有大振幅中尺度重力波的气旋发生：对快速变化的强降水和阵风的影响

• 批准号: 2334171
• 负责人: Michael Kaplan
• 金额: $ 50.08万
• 依托单位: Nevada System of Higher Education, Desert Research Institute
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-01-15 至 2026-12-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2334171&HistoricalAwards=false
• 关键词: Differentiating; Cyclogenesis; without; Large; Amplitude

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.

大气重力波指的是由于初始位移而上升和下降的空气，然后向外传播，就像池塘上的涟漪。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，例如大雪风暴。重力波增强的上升运动可能会导致更强烈的降水和风，使它们与社会密切相关。然而，并不是所有发展中的系统都包含重力波。这项研究项目将利用数值模拟和对有和没有重力波的风暴的观测来研究气旋发展中重力波的原因。这项工作的潜在结果是提高了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。该项目将评估迅速发展的中纬度气旋及其与重力波产生的关系。研究小组的理论是，预测气旋发生和气旋演化期间的重力波需要一个多尺度理论，将动力学演化与其前驱环境分开。气旋形成的演变将与重力波的产生、扩大和维持进行相互比较，目的是创造一种理论，可靠地将重力波耦合气旋与非重力波气旋区分开来。将被检验的具体假设是，对于具有大振幅重力波的气旋发生，对流层中上部等熵位涡的位相更集中在非平衡急流出口区气流中，地转极大值与总风极大值、对流层中上部暖锋和非绝热加热之间的分离较大。为了解决这一假设，将采用基于案例研究的数值模拟方法，使用1公里嵌套结构中的WRF-ARW模式。建模工作将包括全物理模拟，根据观测进行验证，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NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。