VORTEX2: Multiscale Analyses of Tornadic Storms Using Multiparameter Mobile Radars

VORTEX2：使用多参数移动雷达对龙卷风进行多尺度分析

• 批准号: 0802717
• 负责人: Michael Biggerstaff
• 金额: $ 78.77万
• 依托单位: University of Oklahoma Norman Campus
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-12-01 至 2012-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0802717&HistoricalAwards=false
• 关键词: VORTEX2; Multiscale; Analyses; Tornadic; Storms

Intellectual merit: The Verification of Origins of Rotation in Tornadoes Experiment #2 (VORTEX 2) is a multi-scale investigation of factors that lead to tornadogenesis. VORTEX 2 is a follow on to VORTEX 1 whose field phase was conducted during the Spring of 1994 and 1995. The VORTEX 1 advanced knowledge of the kinematic structures of tornadic and nontornadic storms and provided some hints as to the sensitivity of the evolution of supercell storms and tornadogenesis to very fine spatial scale heterogeneity. The VORTEX 2 community intends to extend and build upon the results of VORTEX 1. The research supported under this proposal addresses the stormscale circulations, and thermodynamic and precipitation variability that affect the development and distribution of vorticity in tornadic storms. The primary data set common to these research objectives are Doppler and polarimetric radar observations over the entire breadth and depth of the parent tornadic storm and its immediate environment. C-band radars, with their ability to both penetrate heavy precipitation and sense the clear-air inflow associated with supercell storms, are required. Although the Principal Investigators will cover the entire depth of the storm with two C-bands, frequent coordinated sampling of the lowest 3 kilometers will be made with a X-band dual-polarimetric radar to examine the microphysics and dynamics of the rear-flank downdraft and angular momentum beneath the mesocyclone. These three radars will be tightly coordinated to provide the storm-scale circulation and precipitation structure needed to place finer-scale observations from other instruments into the context of larger-scale storm and environmental flow. The scientific objectives of this research are to study: (i) vorticity dynamics associated with low-level rotation in supercells, (ii) the role of angular momentum transfer on tornadogenesis (iii) precipitation and thermodynamics of the rear-flank downdraft, (iv) the impact of environmental heterogeneity (including boundaries) on storm evolution, (v) the role of cell mergers on tornadogenesis, (vi) the evolution of polarimetric signatures within tornadic and non-tornadic supercells, and (vii) improvements in the analysis and forecasting of tornadic storms through the use of ensemble Kalman-filtering data assimilation. Broader impacts: According to the 1997 Workshop on Societal and Economic Impacts of Weather, tornadic storms account for about 73 fatalities each year and have an average economic impact of about $700M. While lead times associated with tornado warnings have increased with the National Weather Service (NWS) Doppler modernization and forecaster training program, false alarm rates have essentially remained flat. The lack of improvement in false alarms reflects lack of understanding of the physical processes that can cause or limit tornadogenesis. The research conducted here will improve fundamental knowledge, enabling better conceptual models and improved forecasting ability. The improved data assimilation and numerical weather prediction techniques will aid forecasters in their efforts to better warn the public. The independent dual-polarization and multiple-Doppler derived wind fields will aid in storm process and model validation studies. The dual-polarization data will provide an early indication of polarimetric signatures associated with tornadogenesis, if they exist, which will maximize the benefit of the dual-polarimetric upgrade of the NWS operational radar network. The datasets will also be used in university classes from freshman orientation to graduate level term projects. Computer-based teaching modules will be developed and made available to the community.

智力优点：龙卷风实验中旋转起源的验证＃2（Vortex 2）是对导致龙核病发生的因素的多尺度研究。 涡旋2是对涡流1的遵循，其野外阶段是在1994年和1995年进行的。涡旋1对龙卷风和非义龙风暴运动学结构的高级知识，并提供了一些提示，以提示超级细胞风暴的演变和龙卷风的敏感性，以及非常良好的空间尺度尺度均匀尺度的旋律。 Vortex 2社区打算扩展和建立涡旋1的结果。根据该提案支持的研究涉及暴风雨范围的循环，以及影响龙卷风风暴中涡度发展和分布的热力学和降水可变性。 这些研究目标共有的主要数据集是多普勒和偏光雷达观测值，对父母龙卷风风暴的整个广度和深度及其直接环境。 需要C频段雷达，具有穿透大量降水并感知与超级电池风暴相关的透明空气流入的能力。 尽管主要研究人员将用两个C波段覆盖风暴的整个深度，但最低3公里的频繁协调采样将使用X波段的双极度雷达进行，以检查后边缘下降的微型物理学和动力学，并在中间旋风下方进行角动量。 这三个雷达将紧密地协调，以提供风暴规模的循环和降水结构，将其他仪器的较优质观测值放置在大规模风暴和环境流的背景下。这项研究的科学目的是研究：（i）与超级电池中低级旋转相关的涡度动态，（ii）角动量转移对龙卷力生成（III）降水和后边缘下降的降水和热力学的作用（vi）通过使用集成kalman过滤数据同化，龙卷风和非龙核超级细胞内极化特征的演变以及（vii）在分析和预测龙卷风风暴中的改进。更广泛的影响：根据1997年对天气的社会和经济影响的研讨会，龙卷风风暴每年约为73人死亡，平均经济影响约为7亿美元。 尽管国家气象局（NWS）多普勒现代化和预报员培训计划增加了与龙卷风警告相关的交货时间，但错误的警报率基本上保持平坦。 虚假警报缺乏改进反映出对可能导致或限制龙核病的物理过程的理解不足。 这里进行的研究将改善基本知识，实现更好的概念模型并提高预测能力。 改进的数据同化和数值天气预测技术将有助于预测者更好地警告公众。 独立的双极化和多个多个衍生的风场将有助于风暴过程和模型验证研究。 双极化数据将提供与龙卷风发生相关的偏振学特征的早期指示，如果它们存在，这将最大程度地提高NWS操作雷达网络的双偏光升级的好处。这些数据集也将用于大学课程，从新生导向到研究生学期项目。 基于计算机的教学模块将被开发并提供给社区。