CMG Collabortative Research: The Oceanic Internal Wave Energy Spectrum - Synthesis of Theory and Observations

CMG 合作研究：海洋内波能量谱 - 理论与观测的综合

• 批准号: 0417466
• 负责人: Kurt Polzin
• 金额: $ 21.84万
• 依托单位: Woods Hole Oceanographic Institution
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-01 至 2008-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0417466&HistoricalAwards=false
• 关键词: CMG; Collabortative; Research; Oceanic; Internal

The proposed effort is a synthesis of theory and observations of theoceanic internal wavefield. The work proposed is a trulycollaborative effort: the analysis of oceanic observations to groundtruth new theoretical descriptions of internal wave dynamics. Thetheoretical work proposed involves the use of a novel Hamiltonianformalism for the internal wave field, recently developed by thePI's. This has already been shown to include the high--frequencycomponent of the celebrated Garret--Munk spectrum as an exactstatistically stationary solution, as well as to account for much ofthe observed spectral variability. It is proposed to develop aselection principle, based on a combination of wave turbulence andasymptotic analysis, to determine how each oceanic realization of thisvariability is tied to the local nature of the forcing anddissipation, as well as to the latitude dependence of the Coriolis effect.Water in the ocean abyss is denser than water at the surface. Thisdensity stratification permits a class of waves within the oceaninterior, called internal waves. These waves are apparent as thedistortion of density surfaces, and their wave-like properties are dueto the restoring force of gravity. Internal waves are one of themajor player in ocean dynamics, as they can propagate over bigdistances, interact with each other and other major players in theocean, like vorticity and currents, internal waves break and mixwater. While involved in this complex dynamics, internal wavesredistribute mass, momentum, energy and tracers in the ocean.Understanding internal waves is a key element to understanding climatevariability, especially over long time periods. The most difficultpiece of this puzzle is the interaction of internal waves. The investigatorshave already contributed significantly to the understanding ofnonlinear internal wave interactions by demonstrating the existence ofan infinite family of statistically stationary solutions for theinternal wave spectrum, of which the celebrated Garrett and Munkspectrum is a member. Now they propose to investigate whetherparticular members of this infinite family are more likely thanothers, as well as quantify the effects of interaction of internalwaves with other key players in the ocean. This research will beaided by the ongoing analysis of oceanic data sets and will contributecrucial missing components to the theory of ocean mixing, weather and,ultimately, climate.

所提出的努力是海洋内部波场理论和观测的综合。 所提出的工作是一项真正的协作努力：对海洋观测进行分析，以得出内波动力学的新理论描述。 所提出的理论工作涉及使用 PI 最近开发的一种新颖的哈密顿形式主义来研究内波场。这已经被证明包括著名的 Garret-Munk 频谱的高频分量作为精确的统计平稳解，​​并解释了大部分观察到的频谱变化。建议开发一种基于波浪湍流和渐近分析相结合的选择原理，以确定这种变化的每个海洋实现如何与强迫和耗散的局部性质以及科里奥利效应的纬度依赖性联系起来。深海中的水比表面的水密度更大。 这种密度分层允许海洋内部出现一类波，称为内波。这些波表现为密度表面的扭曲，它们的波状特性是由于重力的恢复力造成的。 内波是海洋动力学的主要参与者之一，因为它们可以传播很远的距离，彼此之间以及海洋中的其他主要参与者相互作用，如涡度和洋流、内波破裂和混合水。在参与这种复杂的动力学过程中，内波会重新分配海洋中的质量、动量、能量和示踪剂。了解内波是了解气候变化的关键要素，尤其是在很长一段时间内。 这个难题中最困难的部分是内波的相互作用。 研究人员通过证明内波谱统计平稳解的无限族的存在（著名的加勒特和芒克谱就是其中的成员），已经为理解非线性内波相互作用做出了重大贡献。 现在，他们提议调查这个无限家族的特定成员是否比其他成员更有可能出现，并量化内波与海洋中其他关键参与者相互作用的影响。 这项研究将得到对海洋数据集的持续分析的帮助，并将为海洋混合、天气以及最终的气候理论贡献重要的缺失组成部分。