An Analysis of the Evolution and Structure of Supercell Storms and Tornadoes

摘要本研究对气象雷达和观测资料进行了持续的分析，主要集中在三个方面：(1)记录超级单体风暴的演变过程，包括影响龙卷风形成和龙卷风演变的物理过程；(2)记录龙卷风中观测到的低层风场和旋涡结构；(3)扩展基于雷达的龙卷风气候学。考虑到收集了解龙卷风形成、龙卷风演变和龙卷风风场结构所必需的高分辨率三维数据集的困难，提出的工作有可能促进我们对龙卷风尺度过程的理解，特别是在有限数量的情况下，也可以获得详细的地面观测。经过多年的积累，以前收集的数据已经产生了一套独特的广泛的龙卷风风场测量。从这项研究中获得的知识是至关重要的，因为在龙卷风和风暴尺度上，个别情况具有内在的可变性。收集（和分析）统计上大量的龙卷风样本的测量值是正确理解所涉及的动力学的必要条件。这项研究将进一步扩大该研究小组先前开发的龙卷风气候学中包含的病例数量。更广泛的影响这项研究将利用这些风暴的大量现场观测数据集，提高我们对与龙卷风相关的风场的认识。这些知识将有助于完善龙卷风形成、动力学和演化的概念模型。这项研究的重点是回答与龙卷风的形成和龙卷风涡旋风结构有关的长期问题。在这项研究中进行的研究将改善未来风暴尺度的数值天气预报工作。研究人员将与全国各地的几所大学合作，将这些新知识注入到有关强风暴和龙卷风研究的课程中。

AbstractThis study involves continued analysis of weather radar and observational data along three main focus areas: (1) documentation of supercell storm evolution including the physical processes that affect tornadogenesis and tornado evolution, (2) documentation of the observed low-level wind field and vortex structure in tornadoes, and (3) the expansion of a radar-based tornado climatology. Given the difficulties in collecting the high resolution three-dimensional data sets necessary to understand tornadogenesis, tornado evolution, and tornadic wind field structures, the proposed work has the potential to advance our understanding of tornado-scale processes, especially in the limited number of cases where detailed surface-based observations are also available.Intellectual MeritAccumulated over many years the previously collected data has produced a uniquely extensive set of tornado wind-field measurements. The knowledge gained from this study is critically important given the inherent variability of individual cases on both the tornado and storm scales. The collection (and analysis) of measurements of a statistically large sampling of tornadic storms is required to properly understand the dynamics involved. This study will further expand the number of cases included in the tornado climatology previously developed by this team of researchers. Broader ImpactsThis study will improve our knowledge of wind fields associated with tornadoes, using a large data set of field observations of these storms. This knowledge will help refine conceptual models of tornado formation, dynamics and evolution. This research is focused on answering long-standing questions relating to the formation of tornadoes and tornado vortex wind structure. The research performed in this study will improve future storm-scale numerical weather prediction efforts. The investigators will collaborate with several universities across the country, to infuse this new knowledge into the curriculum involved in the study of severe and tornadic storms.