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; 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.

冰雹是恶劣天气的最危险和破坏性的表现之一，导致全球平均每年的保险财产损失超过100亿美元。除了对个人和商业财产的强烈冰雹影响外，农业和可再生能源部门也受到影响。先进的极化天气雷达是远程检测到云中冰雹，估算其大小的最佳仪器，如果受到预测冰雹增长及其表面影响的物理云模型的指导，则会及时发出冰雹的警告。但是，现有的量化和预测大冰雹的方法具有严重的局限性，该项目将由于该项目而受到减轻。该项目将利用从过去的多次野外运动中渗透到冰雹风暴的装甲T-28研究飞机中对冰雹的独特观察。结合高空云中的直接冰雹测量结果，并在表面上与云建模相结合，描述了其在地面的方式以及在暴风雨的整个深度内的偏光层雷达观察结果，将有助于更好地理解冰雹生成的微物理过程，并开发出更先进的方法，以进行量化和预测的量度。冰雹高昂以初始化云模型。该模型涉及光谱箱微物理学，描述了冰雹的演变，包括冰雹尺寸和动能的变化，随着暴风雨的身高，它们掉落到表面。云模型的输出将转换为极化雷达变量的垂直轮廓，这些变量将与相关的测量曲线进行比较。这将允许使用与熔化层和下方熔化冰雹相关的雷达变量的垂直轮廓在熔融层上方检索冰雹的尺寸分布，并将作为云模型的评估和优化的观察参考。深度对流的高度雷达预测指标将在表面表示大型或巨型冰雹的深度冰雹中，并将在各种热力学和气候状态和气候状态以及表面上的高度相对于海平面，并使用Operational WSR-88D雷达在巨大的统计范围内收集的偏光雷达数据相对于海平面的高度，并涉及型号的统计范围。通过使用基金会的知识分子和更广泛影响的评论标准来通过评估来支持。