Collaborative Research: Origin, Dynamics and Transport Characteristics of the Large-Scale Eddy-Driven Patterns

海洋中尺度变化的主要后果之一是自发产生空间尺度上连贯、缓慢演变的模式，大大超过初级斜压不稳定的主导尺度。 这些大尺度涡驱动模式（LEDP）产生和维持的中尺度涡和初步结果表明，LEDP代表了很大一部分的变化在海洋中。 此外，LEDP可以在热量、盐度、生物地球化学示踪剂和动量的传输中发挥重要作用。 因此，这是至关重要的，以提高我们对这些间接的涡流效应的理解，特别是在考虑到需要提高未来气候projects.Analytical模型之间的相互作用的初级（中尺度）和二级（LEDP）结构的准确性将使用多尺度技术开发。 多尺度方法非常适合这项任务，因为它们的透明度和能力，以代表不同的空间和时间尺度上的现象之间的相互作用。 我们的方法的新奇在于多尺度方法的应用程序中实现的主要涡流模式在典型的海洋流动。 这将使人们有可能提供一个现实的描述LEDP，直接适用于，并可测试的，观察和综合模型。 理论模型将通过具有越来越多的真实性的数值模拟层次来指导和验证，这也将侧重于LEDP的特性和动态。 分析研究，反过来，将被广泛用于解释的数值结果。 这些方法的结合将揭示中尺度涡旋和LEDP之间的复杂相互作用，不可能通过单独的数值模拟，并描述由LEDP的作用引起的涡旋输送特性。 具体的研究任务包括分析：LEDP的形成机制;由这些结构引起的示踪剂的各向异性分散;以及背景状态对LEDP动力学的影响。海洋变率在气候动力学中起着重要但知之甚少的作用。 横向涡动输送是海洋热量、营养盐、污染物和其他示踪物输送的基本组成部分。 因此，需要进一步了解海洋中涡旋引起的迁移和低频变异，以提高气候预测能力，最终产生社会效益。 从理论和模型运行的推论将有助于解释观测数据集，并在未来的观测战略，旨在解释大规模的流量变化的规划。 除了海洋学上的重要性外，这项研究还将对基础流体力学、地球物理学和气候科学产生重大影响。 在这个项目中，一个博士。RSMAS的一名学生和一名博士后助理将参加计划的研究活动，并发展涡旋海洋动力学方面的专门知识。 此外，两名研究生（MS）海军学生将在与本提案相关的主题上进行论文研究，而无需支付项目费用。

One of the principal consequences of mesoscale variability in the ocean is the spontaneous generation of coherent, slowly evolving patterns on spatial scales significantly exceeding the dominant scale of primary baroclinic instability. These Large-Scale Eddy-Driven Patterns (LEDPs) are generated and maintained by mesoscale eddies and preliminary results indicate that LEDPs represent a substantial fraction of variability in the oceans. Furthermore, LEDPs can play an important role in the transport of heat, salinity, bio-geo-chemical tracers, and momentum. Thus, it is vital to improve our understanding of these indirect eddy effects, especially in light of the need for the increased accuracy of future climate projections.Analytical models for the interaction between primary (mesoscale) and secondary (LEDP) structures will be developed using multi-scale techniques. Multi-scale methods are ideally suited to this task due to their transparency and ability to represent interactions between phenomena operating on distinct spatial and temporal scales. The novelty of our approach lies in the application of multi-scale methods to the primary eddy patterns realized in typical oceanic flows. This will make it possible to offer a realistic description of LEDPs, directly applicable to, and testable by, observations and comprehensive models. Theoretical models will be guided and validated by a hierarchy of numerical simulations with an increasing degree of realism, which will also focus on the properties and dynamics of LEDPs. Analytical studies, in turn, will be used extensively for interpretation of the numerical results. The combination of these approaches will reveal the complex interplay between mesoscale eddies and LEDPs, not possible through numerical simulation alone, and describe the eddy transport characteristics induced by the action of LEDPs. Specific research tasks include the analysis of: the formation mechanisms of LEDPs; the anisotropic dispersion of tracers induced by these structures; and the effects of the background state on LEDP dynamics.Oceanic variability plays an important, but poorly understood role in climate dynamics. Lateral eddy transfer is a fundamental component of the oceanic transport heat, nutrients, pollutants and other tracers. Thus, advances in the understanding of eddy-induced transport and low frequency variability in the oceans are needed to improve climate prediction capabilities, ultimately leading to societal benefits. Inferences from the theory and model runs will aid in the interpretation of observational data sets and in the planning of future observational strategies aimed at explaining large scale flow variability. In addition to its oceanographic importance, this study will have significant implications for fundamental fluid mechanics, geophysics and climate science. During this project, one Ph.D. student at RSMAS and a postdoctoral associate at NPS will participate in the planned research activities and develop expertise in eddying ocean dynamics. In addition, two graduate (MS) Navy students will perform their thesis research at NPS on topics related to this proposal at no cost to the project.