Investigation of Persistent and Coherent Structures in Geophysical and Turbulent Flow

本研究包括理论、数值和 的自由解的观测研究 流体运动，以理解持续和 大气和流体湍流中的相干结构。 这样的结构是数值模拟中普遍存在的特征 和大规模的大气流动。 了解它们如何 演变并影响它们所嵌入的湍流 在地球物理流体动力学中也很重要 在长期可预测性方面具有实际重要性。 PI最近发现了潜在的强大方法 这使得稳定的稳定的解决方案可以从一个 非定常初始状态，同时保持涡度结构， 或签名，初始状态。 他们将利用这种 方法在调查观察到的持续现象， 大气层，并系统地调查 构造运动方程的稳定解， 三维、二维和准地转流。 他们还将进行理论和数值研究 以及相关技术。 的一般意义 工作是使用的方法将阐明的性质， 湍流和地球物理流中的持久结构， 将它们与运动方程的自由解联系起来。 的 这些方法还提供了构建新的、稳定的、流体的、生物相容性的方法。 配置. 天气和气候系统是 因此这项研究可能会导致 更好地了解这些系统。

This research includes theoretical, numerical and observational studies of the free solutions of the equations of fluid motion, with the goal of understanding persistent and coherent structures in the atmosphere and in fluid turbulence. Such structures are ubiquitous features of numerical simulations and of large scale atmospheric flow. Understanding how they evolve and affect the turbulent flow in which they are embedded is fundamentally important in geophysical fluid dynamics, as well as being of practical importance in long range predictability. The PIs have recently discovered potentially powerful methods which enable steady stable solutions to be constructed from an unsteady initial state, while preserving the vorticity structure, or signature, of the initial state. They will utilize such methods in an investigation of observed persistent phenomena in the atmosphere, and to systematically investigate the construction of steady solutions of the equations of motion, for three dimensional, two-dimensional and quasi-geostrophic flow. They will also perform theoretical and numerical investigations of this and related techniques. The general significance of the work is that use of the methods will elucidate the nature of persistent structures in turbulence and in geophysical flow, by relating them to free solutions of the equations of motion. The methods also provide the means to construct new, stable, fluid configurations. Weather and climate systems are manifestations of geophysical turbulence and so this research may lead to improved understanding of these systems.