Weddell Sea Upper Ocean Turbulence Analysis Modeling

威德尔海上层海洋湍流分析建模

• 批准号: 9725478
• 负责人: Miles McPhee
• 金额: --
• 依托单位: McPhee Research Company
• 依托单位国家: 美国
• 项目类别: Continuing grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-05-15 至 2002-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9725478&HistoricalAwards=false
• 关键词: Weddell; Sea; Upper; Ocean; Turbulence

*** 9725478 McPhee This study is concerned with the analysis of an extensive data set obtained by the principal investigator in the context of two interdisciplinary field projects in the Weddell Sea: the Joint U.S.-Russian Ice Camp in 1992 and Anzflux in 1994. The data set consists of direct measurements of Reynolds stresses and turbulent heat fluxes in the uppermost 100 meters of the ocean under a continuous sea ice cover, and was the first such observations made in the Southern Ocean. The objective of the analysis is continued development of a turbulence closure technique in the numerical modelling of the upper ocean, and to describe the structure of boundary layer turbulence under exceptionally wide ranges of surface stress and buoyancy flux. A frequent criticism of current upper ocean models is that their representations of turbulent exchange processes are arbitrarily adjusted to reproduce the few available observed time series of upper ocean structure. This work will provide the basis for a significantly improved modelling of upper ocean turbulence by requiring the model algorithms to reproduce a wide range of turbulence intensities, and will include a novel approach to specifying the eddy properties of the upper ocean. These analyses, in conjunction with concurrent analyses of other experiments carried out in the two field projects, will produce a framework for quantifying the energy brought to the underside of the ice, and will form the basis of a regional study of the processes responsible for the relatively thick upper mixed layer and thin ice cover. It is believed that the sea ice cover is only marginally stable in the face of the high upward heat flux, and if this were interrupted, could lead to deep vertical convection and a significant change in the ocean climate. ***

* 9725478 McPhee本研究涉及对主要研究者在威德尔海两个跨学科实地项目中获得的广泛数据集的分析：1992年的俄罗斯冰营和1994年的Anzflux。该数据集包括在连续海冰覆盖下海洋最上层100米处的雷诺应力和湍流热通量的直接测量，是在南大洋进行的第一次此类观测。分析的目的是继续发展上层海洋数值模拟中的湍流闭合技术，并描述在非常宽的表面应力和浮力通量范围内的边界层湍流结构。当前上层海洋模式经常受到的批评是，它们对湍流交换过程的描述被任意调整，以重现少数可用的上层海洋结构观测时间序列。这项工作将提供一个显着改善上层海洋湍流建模的基础上，要求模型算法，以再现广泛的湍流强度，并将包括一种新的方法来指定的涡流特性的上层海洋。这些分析，加上同时对两个实地项目中进行的其他实验进行的分析，将产生一个框架，用于量化冰底的能量，并将成为对造成较厚的上混合层和薄冰盖的过程进行区域研究的基础。据信，海冰覆盖面在高向上热通量面前只是勉强稳定，如果中断，可能导致深层垂直对流和海洋气候的重大变化。***