VORTEX 2: Storm-scale Baroclinity Using Fine-scale Observations and Numerical Models

这一奖项是多名调查员共同努力的一个组成部分，这项工作被称为龙卷风实验2(涡旋2)中旋转起源的核实。涡旋2是涡旋1的后续，涡旋1的场阶段是在1994年和1995年春季进行的。涡旋1提高了对龙卷风和非龙卷风的运动学结构的认识，并提供了一些关于超单体风暴和龙卷风的演化对非常精细的空间尺度非均质性的敏感性的线索。涡旋2的研究目标将集中在龙卷风的发生和维持以及龙卷风的近风场结构上。涡旋2号正在与美国国家海洋和大气管理局联合进行，它将涉及一个史无前例的固定和移动设施观测网络，其中包括多普勒雷达、地面和高空观测。。众所周知，超级单体雷暴包含潜在的显著的热力学和运动学梯度，其中许多被怀疑与低水平的中热带气旋生成有关。由于在以前的数值研究中已经解决了虚拟位温的强梯度，风暴尺度的斜压性被怀疑在水平涡度的斜压产生中起作用，在某些情况下，水平涡度可以被风暴的主要上升气流倾斜和拉伸。尽管到目前为止，现场收集的相对稀少的现场观测已经为斜压问题提供了一些线索，但这些观测通常在空间分辨率上很差。该奖项下的研究的智力价值来自于新开发的“粘性网络”技术的引入，即一系列快速部署的地面站。这些系统将在涡旋2期间部署，以从龙卷风发生和验证/改进风暴尺度数值天气预报模式的角度处理风暴尺度斜压性问题。这些测量将提供超单体中气旋附近热力学和运动量变化的史无前例的细节，结合从双多普勒分析和数值模式计算的气团轨迹，将允许建立进入低层中气旋的气团的涡度预算。StickNet的测量还将深入了解多风暴相互作用的哪些特性有利于龙卷风的发生和龙卷风的维持。StickNet的数据还将用于验证风暴尺度的数值模式，并将为验证和改进现有的热力学反演技术方法提供基础。这项研究的更广泛影响将从多个方面感受到。将利用一些研究生和本科生来规划和执行StickNet数据收集。这些学生中的一些人拥有气象学(如风能工程)以外的其他领域的背景，因此将有机会扩大他们的知识库。鉴于德克萨斯理工大学学生群体的典型种族多样性，预计传统上代表性较低的群体，特别是西班牙裔群体，将有充分机会参与VORTEX2的StickNet部分。这项研究的最终目标是通过实时观测和短期数值模拟来改进强雷暴和龙卷风预报。这种预测技能的提高对保护生命和财产至关重要。通过在期刊出版物和会议报告中广泛传播研究成果，所有达到的研究目标都将在社会上产生重大影响。

This award is one component of a mutli-investigator effort known as the Verification of the Origins of Rotation in Tornadoes Experiment 2 (VORTEX 2). 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 research objectives will focus on the genesis and maintenance of tornadoes and on the structure of the near wind field of the tornado. The VORTEX 2 is being conducted in conjunction with the National Oceanic and Atmospheric Administration and it will involve an unprecedented observational network of stationary and mobile facilities that include Doppler radars, surface and upper air observations. . Supercell thunderstorms are known to contain potentially significant thermodynamic and kinematic gradients, many of which are suspected to be relevant to low-level mesocyclogenesis. Owing to the strong gradients in virtual potential temperature that have been resolved in prior numerical studies, storm-scale baroclinity is suspected to play a role in the baroclinic generation of horizontal vorticity, which can be tilted and stretched by the principal updraft of the storm in some circumstances. Though the relatively sparse in-situ observations gathered in the field to this point have shed some light on the issue of baroclinity, these observations are typically poor in spatial resolution.The intellectual merit of the research under this award follows from the introduction of newly-developed "StickNet" technology, an array of rapidly-deployable surface stations. These systems will be deployed during VORTEX 2 to address the issue of storm-scale baroclinity both from the standpoint of tornadogenesis and the verification/improvement of storm-scale numerical weather prediction models. These measurements will provide unprecedented detail of variations in thermodynamic and kinematic quantities in close proximity to supercell mesocyclones which, in combination with air parcel trajectories calculated from dual-Doppler analyses and numerical models, will permit the construction of a vorticity budget for air parcels entering the low-level mesocyclone. StickNet measurements will also provide insight into what properties of multi-storm interactions are favorable to tornadogenesis and tornado maintenance. The StickNet data also will be used to validate numerical storm-scale models and also will provide a basis for verification and improvement of existing methods of thermodynamic retrieval techniques. The broader impacts of the study will be felt in a number of ways. A number of graduate and undergraduate students will be utilized in the planning and execution of StickNet data collection. Some of these students have background in fields other than meteorology (e.g., wind engineering), and therefore will have the opportunity to expand their knowledge base. Given the typical ethnic diversity of the student population at Texas Tech University, it is expected that traditionally underrepresented groups, particular those of Hispanic descent, will have full opportunity to participate in the StickNet component of VORTEX2. The ultimate goal of the research is the improvement of severe thunderstorm and tornado forecasts, both through real-time observation and short-term numerical modeling. This increase in forecast skill is of utmost importance for the protection of life and property. Through the broad dissemination of research results in journal publications and conference presentations, all research objectives that are met will have significant impact in the community.