Tropical Cyclogenesis via Non-Axisymmetric Upscale Energy Cascade and Its Disruption by Vertical Shear

该项目涉及沿沿着三条途径研究热带气旋的生成和发展。 PI和他的小组以前的工作推进了对涡旋轴对称化的理解，其中平均涡旋通过使用相当简单的模型的高档能量级联过程以牺牲小尺度涡度异常为代价而增强。 作为研究的第一个途径，PI将在各种初始条件下使用更现实的三维云解析模型进一步探索理论的有效性。 第二个途径是检查和确定高档能源级联中断的条件。 如果一个正压涡旋从它的旋转轴倾斜，它可能会也可能不会回到它的直立位置（对齐），并破坏高档的能量级联。 这项工作旨在确定的条件，使有限的Rossby数涡抵抗垂直剪切的不利影响。 第三个途径将是使用1991年完成的热带气旋现场实验的机载多普勒雷达数据来检验理论。 这部分工作将与人力资源开发部的Frank Mark和Paul Reasor博士以及SUNY/奥尔巴尼的Lance Bosart教授合作完成。 该项目的结果有可能提高对热带气旋生成的认识，并改进热带气旋强度的预测。

This project involves studies of tropical cyclogenesis and development along three avenues. Previous work by the PI and his group advanced the understanding of the axisymmetrization for vortices where the mean vortex intensifies at the expense of the small-scale vorticity anomalies through an upscale energy cascade process using a fairly simple model. As the first avenue of investigation, the PI will further explore the validity of the theory using a more realistic three-dimensional cloud-resolving model under various initial conditions. The second avenue is to examine and determine the conditions for the disruptions of the upscale energy cascade. If a barotropic vortex is tilted from its rotation axis, it may or may not return to its upright position (alignment) and disrupt the upscale energy cascade. This work seeks to determine the conditions that enable a finite Rossby number vortex to resist the adverse effects of vertical shear. The third avenue will be the testing of the theory using the airborne Doppler-radar data from a tropical cyclone field experiment done in 1991. This part of the work will be done in collaboration with Drs. Frank Mark and Paul Reasor of HRD and Prof. Lance Bosart of SUNY/Albany. The results of this project have the potential to enhance the understanding of tropical cyclogenesis and to improve the prediction of tropical cyclone intensity.