Collaborative Research: Comparison between In-situ and Polarimetric Radar Hail Observations in Convective Storms

美国的作战天气雷达系统利用偏振观测，雷达波束以垂直和水平的配置发出，以获取对降水粒子形状的估计。这项奖励将利用现有的极化雷达数据和风暴穿透飞机(SPA)的观测数据，以改进对雷达数据中冰雹特性的估计。冰雹是一种公共安全和经济危害，改进的关于冰雹的雷达信息可以为业务预报员提供额外的工具来提供早期预警。多名学生将在该项目下接受培训，科学界使用的软件将得到增强。研究小组计划重新审视现有的冰雹观测，这些观测是与一架研究飞机和偏振雷达同时进行的，以深入了解冰雹的形状、方向、大小和浓度如何影响雷达信号。南达科他州矿业与技术学院在1987年至2003年期间，在国家科学基金会的支持下，操作了一架T-28风暴穿透飞机。在此期间，这架飞机参与了18个项目，其中许多项目包括使用冰雹分光仪和云探测器测量冰雹。这些活动通常在双极化雷达的近距离内进行，包括CSU-CHILL和NCAR SPOL雷达。在该项目中，将增加新的航班和飞行周期，纳入云和降水探测器(2D-C、HVPS)的数据，以及记录冰雹撞击飞机挡风玻璃声音的麦克风的独特数据来源，从而加强对这些数据的现有分析。主要任务包括：1)处理来自分光计探测器的水气象图像，包括使用离散偶极子和T-矩阵软件计算极化雷达信号，2)分析雷达数据以识别雷达扫过风暴体积与冰雹相遇的时间，以及3)数据合成，目的是比较导致计算和观测雷达信号更好或更差一致性的条件的特征，该项目由地球科学局和高级网络基础设施办公室共同资助，以支持AI/ML和地球科学中的开放科学活动。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。

The system of operational weather radars in the United States makes use of polarimetric observations, where radar beams are sent out in vertical and horizontal configurations to retrieve an estimate of the shapes of precipitation particles. This award will make use of existing polarimetric radar data and observations from a Storm Penetrating Aircraft (SPA) to improve estimates of the properties of hail from radar data. Hail is a public safety and economic hazard, and improved radar information about hail could provide operational forecasters with an additional tool to provide early warnings. Multiple students will be trained under this project and software used by the scientific community will be enhanced.The research team plans to revisit existing observations of hail that were made concurrently with a research aircraft and polarimetric radars to provide insight into how hail shapes, orientation, sizes, and concentrations influence radar signatures. The South Dakota School of Mines and Technology operated a T-28 storm penetrating aircraft under NSF support from 1987-2003. During that time, the aircraft was involved in 18 projects, many of which included measurements of hail using a hail spectrometer and cloud probes. These campaigns were often conducted within a close distance of a dual-polarimetric radar, including the CSU-CHILL and NCAR SPOL radars. In this project, existing analyses of these data will be augmented by the addition of new flights and flight periods, the inclusion of data from cloud and precipitation probes (2D-C, HVPS), and a unique source of data from a microphone that recorded the sound of hail hitting the aircraft windshield. The main tasks include: 1) Processing hydrometeor images from spectrometer probes, including the calculation of polarimetric radar signatures using discrete dipole and T-matrix software, 2) Analyzing radar data to identify the time the radar swept through the storm volume with the hail encounter and extraction of polarimetric parameters, and 3) Synthesis of the data, with objectives of comparing characteristics of conditions leading to better or worse agreement of computed and observed radar signatures, and evaluation of hail physical characteristics to which each computed polarimetric parameter is most sensitive.This project is co-funded by a collaboration between the Directorate for Geosciences and Office of Advanced Cyberinfrastructure to support AI/ML and open science activities in the geosciences.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.