Mesoscale Vortex Interactions in Tropical Systems

预测和理解飓风的形成是大气科学中最具挑战性的问题之一。预测飓风的部分困难来自于发展中系统中中尺度涡旋的复杂相互作用。该研究项目旨在阐明发展中系统中的中尺度涡旋相互作用的物理学以及这种相互作用对飓风形成的后果。以下基本问题将得到解决：1。中尺度涡与对流涡合并的条件和机制是什么？合并发生的时间尺度是什么？2.地面风的增强率如何取决于中尺度涡旋相互作用的变化，例如是否发生合并？3.先前的中尺度涡旋相互作用如何影响年轻热带风暴或飓风的大小、强度和不对称结构？上述问题已在过去得到解决，但只有在范围狭窄的案例研究，或更广泛的研究，使用简化的模型与可疑的适用性问题hond.The目前的调查将包括精心设计的计算研究，使用一个国家的最先进的云系统解决数值模式。 这些研究将涉及涡旋参数的变化、大气的热力学状态、涡旋所处的更广泛流动的性质以及调节海气相互作用的参数。额外的数值实验将检查结果的灵敏度的细节的微物理和次网格湍流parameterization.Intellectual优点：这个项目将导致一个全面的，定量的了解对流中尺度涡的相互作用及其后果，在发展中的热带系统。如前所述，这一领域的知识目前仅限于不同的案例研究和简化的建模研究，现实性不足。在一般意义上，该项目的结果不仅将推进动力气象学，而且还基本流体dynamics.Broader影响的更广泛的领域：该项目的结果将提高目前的理解时，准确的飓风预报需要准确的初始化或同化的中尺度涡在预报模拟。 减少飓风预测的不确定性对于规划海事活动和沿海社区的安全措施显然很重要。该项目的教育部分将包括博士后研究人员的高级培训/指导，以及在大学研讨会上的演讲。该项目的成果将通过期刊出版物、会议报告和研究网页影响更广泛的大气科学和物理学界。

Predicting and understanding hurricane formation is one of the most challenging problems in atmospheric science. A part of the difficulty in predicting hurricanes stems from the complex interactions of mesoscale vortices in developing systems. This research project aims to elucidate the physics of mesoscale vortex interactions in developing systems and the consequences of such interactions on the formation of hurricanes. The following fundamental questions will be addressed:1. What are the conditions and prevailing mechanisms for the merger of moist-convective mesoscale vortices, and what is the time-scale for merger to occur?2. How does the intensification rate of surface winds depend on the variability of mesoscale vortex interactions, such as whether or not merger takes place?3. How do prior mesoscale vortex interactions affect the size, intensity and asymmetric structure of a young tropical storm or hurricane?The above issues have been addressed in the past, but only in the context of narrow case studies, or somewhat broader studies using simplified models with questionable applicability to the problem at hand.The present investigation will consist of carefully designed computational studies using a state-of-the-art cloud system resolving numerical model. These studies will involve variation of the vortex parameters, the moist-thermodynamic state of the atmosphere, the properties of the broader flow in which the vortices are situated, and the parameters regulating air-sea interaction. Additional numerical experiments will examine the sensitivity of results to details of the microphysics and subgrid turbulence parameterizations.Intellectual Merit: This project will lead to a comprehensive, quantitative understanding of moist-convective mesoscale vortex interactions and their consequences in developing tropical systems. As noted earlier, knowledge in this area is currently limited to disparate case studies, and simplified modeling studies with insufficient realism. In a general sense, the results of this project will not only advance dynamic meteorology, but also the broader field of fundamental fluid dynamics.Broader Impacts: The results of this project will improve current understanding of when accurate hurricane prediction requires the accurate initialization or assimilation of mesoscale vortices in forecast simulations. Reducing the uncertainty of hurricane prediction is clearly important for planning maritime activities and safety measures for coastal communities. The educational components of this project will include the advanced training/mentoring of a postdoctoral researcher, and presentations at university seminars. The results of this project will impact the broader atmospheric science and physics communities through journal publications, conference presentations, and a research web page.