Severe Convective Storms and Tornadoes

这项研究项目的主要目的是增进对强对流风暴和龙卷风的成因、运动学和动力学的了解。这一目标将主要通过分析在以前和未来的实地试验中收集的数据以及通过数值模拟试验来实现。将对来自现场实验的移动多普勒雷达数据进行分析，以详细说明龙卷风及其母涡的结构和演变，以及与干线有关的垂直环流，强烈对流风暴经常沿着这一特征启动。特别是，为什么一些超级单体风暴会产生龙卷风，而另一些则不会，这将得到调查。对流-风暴相互作用的动力学和干线与斜压边界的交集在触发对流风暴中的作用将通过受控的数值模式模拟实验来研究。此外，将测试两个新的雷达系统，以用于严重风暴/龙卷风研究：一个是移动式、快速扫描、相控阵多普勒雷达；另一个是现有系统，将配备间隔天线，除了视线风向测量外，还可以提供横向风速测量。美国国家科学基金会另一个奖项的合作者正在开发这些雷达系统(安德鲁·帕兹曼博士，ATM-0242166)。如果新的雷达系统成功，那么将有更高质量的数据集可供分析。预计该项目最终将导致对恶劣天气事件的更准确预测。

The main objective of this research project is to improve understanding of the genesis, and the kinematics and dynamics of severe convective storms and tornadoes. The objective will be met primarily through analysis of data collected in both prior and future field experiments and through numerical simulation experiments. Mobile Doppler radar datasets from field experiments will be analyzed to detail the structure and evolution of tornadoes and their parent vortices and the vertical circulation associated with the dryline, a feature along which severe convective storms are often initiated. In particular, why some supercell storms produce tornadoes, while others do not, will be investigated. The dynamics of convective-storm interaction and the role of the intersection of a dryline with a baroclinic boundary in triggering convective storms will be investigated using controlled numerical-model simulation experiments. In addition, two new radar systems will be tested for use in severe storm/tornado research: one is a mobile, rapidly scanning, phased-array Doppler radar; the other is an existing system that will be fitted with a spaced antennae, which could provide transverse-wind measurements in addition to line-of-sight wind measurements. A collaborator under another NSF award is developing these radar systems (Dr. Andrew Pazmany, ATM-0242166). If the new radar systems are successful, then much higher quality datasets will be available for analysis. It is anticipated that this project will ultimately lead to a more accurate prediction of severe weather events.