Collaborative Research: Formation of Multiple Zonal Jets in the Oceans

合作研究：海洋中多个纬向急流的形成

• 批准号: 0842834
• 负责人: Igor Kamenkovich
• 金额: $ 70.85万
• 依托单位: University of Miami
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-04-01 至 2013-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0842834&HistoricalAwards=false
• 关键词: Collaborative; Research; Formation; Multiple; Zonal

Observational and modeling studies have recently demonstrated that the ocean contains multiple, alternating, nearly zonal jets that cover all oceanic basins and penetrate from the top to the bottom of the ocean. The typical width of each jet is 100-300 km, typical velocity is 1-5 cm/s, and the jets are embedded in the large-scale oceanic currents. The oceanic jets may be also dynamically related to the multiple alternating jets in the atmosphere of such giant gas planets as Jupiter. The atmospheric jets have been studied for a few decades, and the atmospheric community developed a set of useful theoretical ideas. The prevailing hypothesis in these theories is that these jets are a nonlinear phenomenon, maintained by eddies. However, not only do the atmospheric jets remain poorly understood, but also the relevance of the corresponding theoretical ideas to the oceanic jets is under question. Potential mechanisms of the multiple jet formation will be studied with a hierarchy of ocean circulation models. The central idea is to understand physical mechanisms that can maintain the observed jets and determine their structure. Specific objectives are to: (i) systematically describe phenomenology of the jets in the context of available observations; (ii) establish dependence of jet properties on various physical factors; (iii) analyze importance of eddy flux convergences and anisotropic mixing within the jets; (iv) examine low-frequency variability associated with the jets, and (v) determine the mechanisms of jet formation. The underlying flow mechanisms and jet properties will be studied both with analysis of the nonlinear solutions and with linear stability analysis of the flow components. Important properties that need to be explained include meridional and vertical structures, amplitude, and transient variability of the jets. Connection will be made to existing atmospheric-jet ideas, as well as to the broader literature on anisotropic turbulence. This project will address fundamental but poorly understood physics of this particular class of oceanic eddy/large-scale interactions, using theory, models, and observations. The work has to do with providing the physical basis for the emerging observations of the multiple jets. Parameterization of highly anisotropic transport associated with these jets is another research topic that will benefit from fundamental understanding of the phenomenon. This project will support one graduate student at the University of Miami.

观察性研究和建模研究最近表明，海洋包含多种覆盖所有海洋盆地的交替，几乎扎实的喷气机，并从海洋的顶部渗透到底部。每个射流的典型宽度为100-300 km，典型的速度为1-5 cm/s，喷气机嵌入大型海洋电流中。海洋喷气机也可能与木星这样巨大气体行星的大气中的多个交替喷气式飞机动态相关。大气喷气机已经进行了几十年的研究，大气社区开发了一系列有用的理论思想。这些理论中的普遍假设是这些喷气机是一种非线性现象，由涡流维持。但是，不仅大气喷气机的理解仍然很少，而且相应的理论思想与海洋喷气机的相关性也受到质疑。通过海洋循环模型的层次结构，将研究多个射流形成的潜在机制。核心思想是了解可以维持观察到的喷气机并确定其结构的物理机制。特定目标是：（i）在可用观察的背景下系统地描述喷气机的现象学； （ii）确定喷气性质对各种物理因素的依赖； （iii）分析喷气机内涡流收敛和各向异性混合的重要性； （iv）检查与喷气机相关的低频变异性，（v）确定射流形成的机制。通过对非线性溶液的分析以及流动成分的线性稳定性分析，将研究基本的流动机制和射流性能。需要解释的重要属性包括子午线和垂直结构，振幅和喷气机的瞬态变异性。将与现有的大气射流思想以及有关各向异性湍流的更广泛文献建立联系。该项目将使用理论，模型和观测值解决基本但知之甚少的海洋涡流/大规模相互作用的物理学。这项工作与为多个喷气机的新兴观察提供物理基础有关。与这些喷气机相关的高度各向异性运输的参数化是另一个研究主题，它将受益于对该现象的基本理解。该项目将支持迈阿密大学的一名研究生。