Collaborative Research: Using Polarimetric Radar Observations, Cloud Modeling, and In Situ Aircraft Measurements for Large Hail Detection and Warning of Impending Hail

合作研究：利用偏振雷达观测、云建模和现场飞机测量来检测大冰雹并预警即将发生的冰雹

• 批准号: 2344259
• 负责人: Alexander Ryzhkov
• 金额: $ 29.84万
• 依托单位: University of Oklahoma Norman Campus
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-04-15 至 2027-03-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2344259&HistoricalAwards=false
• 关键词: Collaborative; Research; Using; Polarimetric; Radar

Hail is one of the most dangerous and destructive manifestations of severe weather, resulting in an annual average of more than $10 billion USD in insured property losses around the world. In addition to the strong hail impact on personal and business property, the agricultural and renewable energy sectors also suffer. Advanced polarimetric weather radars are the best instruments to remotely detect hail in the clouds, estimate its size, and produce timely warnings of impending hail if guided by the physical cloud models that predict hail growth and its fallout on the surface. However, existing methodologies for quantifying and forecasting large hail have serious limitations which will be mitigated as a result of the project. This project will capitalize on the unique observations of hail from the armored T-28 research aircraft that penetrated hail-bearing storms during multiple field campaigns in the past. Combining direct hail measurements within the cloud aloft and at the surface with cloud modeling describing its evolution on the way to the ground and the collocated polarimetric radar observations within the full depth of the storm will help to better understand the microphysical processes of hail generation and develop more advanced methodologies for its quantification and prediction / nowcasting.The technical approach will involve utilization of the documented measurements of sizes, number concentrations, and shapes of hailstones aloft to initialize the cloud model. The model involves spectral bin microphysics describing the evolution of hailstones including the change of hail size and kinetic energy with height within the storm as they fall to the surface. The output of the cloud model will be converted into the vertical profiles of polarimetric radar variables which will be compared to the associated measured profiles. This will allow to retrieve size distribution of hail above the melting layer using vertical profiles of radar variables associated with melting hail within the melting layer and beneath and will serve as an observational reference for cloud models’ evaluation and optimization. Novel polarimetric radar predictors in deep convective updrafts signifying large or giant hail at the surface will be identified and explored across a wide range of thermodynamic and climatological regimes and height of the surface relative to sea level using polarimetric radar data collected by the operational WSR-88D radars in a multitude of particularly devastating hailstorms.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.

冰雹是恶劣天气中最危险和最具破坏性的表现形式之一，每年平均造成全球保险财产损失超过 100 亿美元，冰雹除了对个人和商业财产、农业和可再生能源造成严重影响外。先进的偏振天气雷达是远程探测云中冰雹、估计其大小并在预测冰雹增长及其对地表影响的物理云模型的指导下及时发出冰雹即将发生的警报的最佳仪器。 ，现有方法量化和预测大冰雹的方法存在严重局限性，该项目将利用装甲 T-28 研究飞机对冰雹的独特观测，这些飞机在多次实地活动中穿透了携带冰雹的风暴。将高空云内和地表的直接冰雹测量与描述冰雹到达地面过程中演变的云模型以及风暴整个深度内的并置偏振观测雷达相结合，将有助于更好地了解冰雹生成的微物理过程。并为其量化和预测/临近预报开发更先进的方法。该技术方法将涉及利用记录在案的高空冰雹的尺寸、数量浓度和形状的测量来初始化云模型，该模型涉及描述云演化的光谱箱微物理。冰雹，包括冰雹大小和动能随风暴落到地表时高度的变化，云模型的输出将转换为偏振雷达变量的垂直剖面，并将其与相关的测量数据进行比较。这将允许使用与融化层内和下方的融化冰雹相关的雷达变量的垂直剖面来检索融化层上方冰雹的尺寸分布，并将作为云模型评估和优化的观测参考。在深对流上升气流中，表明地表有大或巨大的冰雹，将使用运营部门收集的极化雷达数据，在广泛的热力学和气候状况以及地表相对于海平面的高度上进行识别和探索。 WSR-88D 雷达在许多特别具有破坏性的冰雹中发挥作用。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力优点和更广泛的影响审查标准进行评估，被认为值得支持。