RAPID: Preliminary Scientific Assessment of the Monroe, Louisiana Tornado on 12 April 2020

2020年4月12日，一场强烈的龙卷风袭击了路易斯安那州的门罗，并造成了重大损失。龙卷风在路易斯安那大学门罗分校（乌尔姆）操作的仪器的近距离内移动，包括天气雷达和其他测量地面和高空风速和温度的仪器。该奖项将使调查小组能够对产生龙卷风的独特风暴系统进行增强的损害调查和初步科学分析。该项目更广泛的社会影响是通过确定导致这场强龙卷风的因素，以便更好地预测未来的恶劣天气。几名学生将参与分析，确保下一代科学家的发展。2020年复活节星期日的门罗龙卷风在乌尔姆操作的S波段双极化雷达1公里范围内移动。此外，还收集了多普勒风激光雷达、微波辐射计和多个地面站的测量结果。龙卷风被嵌入准线性对流系统（QLCS），传统上产生的大多是弱龙卷风。然而，门罗龙卷风是一个强大的EF-3龙卷风，导致人们质疑它是如何达到这种强度的。将使用该龙卷风的测量结果来解决与准线性对流系统（QLCS）龙卷风发生相关的几个假设：1）一个涌动的斜压边界增强了近风暴的QLCS环境，通过局部增加低层（i）风切变，（ii）不稳定性和（iii）辐合，使其更有利于龙卷风的生成，2）相对温暖的QLCS流出促进了表面涡度的拉伸，3）可观测到的雷达反射率结构（如弓形段）可以与QLCS龙卷风发生的成败联系起来，另外，由于龙卷风与乌尔姆雷达的距离很近，可以将雷达数据与破坏路径联系起来，从而提高我们对遥感雷达数据如何与龙卷风实时相关的理解。该项目将收集来自无人机系统的航空图像，以解决这一问题。该奖项反映了NSF的法定使命，并被认为值得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。

On April 12th, 2020, a strong tornado impacted Monroe, Louisiana and produced significant damage. The tornado moved within very close range of instrumentation operated by the University of Louisiana at Monroe (ULM), including a weather radar and other instruments that provide measurements of wind and temperature at the surface and aloft. This award will allow the investigator team to perform an enhanced damage survey and initial scientific analysis of the unique storm system that produced the tornado. The broader societal impact of the project is through the identification of the factors that led to this strong tornado, in order to provide better forecasts of severe weather in the future. Several students will be involved in the analysis, ensuring the development of the next generation of scientists.The Monroe tornado of Easter Sunday 2020 moved within 1 km of the S-band, dual-polarimetric radar operated by ULM. Additionally, measurements from a Doppler wind lidar, microwave radiometer, and multiple surface stations were collected. The tornado was embedded in a Quasi-Linear Convective System (QLCS), which traditionally produce mostly weak tornadoes. However, the Monroe tornado was a strong EF-3 tornado, leading to question about how it reached that intensity. Several hypotheses related to Quasi-Linear Convective System (QLCS) tornadogenesis will be addressed using the measurements from this tornado: 1) A surging baroclinic boundary enhances the near-storm QLCS environment, making it more conducive to tornadogenesis by locally increasing low-level (i) wind shear, (ii) instability, and (iii) convergence, 2) A relatively warmer QLCS outflow promotes stretching of surface vorticity, and 3) Observable radar reflectivity structures, such as bowing segments, can be linked the success or failure of QLCS tornadogenesis.Additionally, given the close approach of the tornado to the ULM radar, links between the radar data and damage path can be made, improving our understanding of how remotely sensed radar data correlates to tornadoes in real-time. The project will collect aerial imagery from UASs to address this issue.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.