Collaborative Research: Modeling Thermobaric Effects in Antarctic Deep Ocean Convection

合作研究：模拟南极深海对流的温压效应

• 批准号: 0125406
• 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: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-03-01 至 2004-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0125406&HistoricalAwards=false
• 关键词: Collaborative; Research; Modeling; Thermobaric; Effects

This collaborative project is a modeling study of thermobaric instability in the ocean, and its effect on deep convection in the Southern Ocean. Thermobaric instability refers to the fact that the compressibility of sea water is a non-linear function of pressure, so that a colder and fresher layer overlying a warmer and a saltier layer may be statically stable, but become unstable if it is disturbed. That this is theoretically possible has been known for a long time, but only recently has it been considered as an effect that could actually occur in the Southern Ocean, specifically as the potential explanation of the episodic occurrence of polynyas (sizable areas of open water within the sea-ice pack) in the Weddell Sea. This evaluation of the impact of thermobaricity on deep ocean convection will be based on a numerical Large Eddy Simulation (LES) model capable of simulating directly the convection plumes and large scale oceanic flow features that would be expected with intense thermobaric overturn. Based on preliminary results of an LES model initialized and forced by conditions observed during previous oceanographic cruises to the Weddell Sea, this proposed work will combine a carefully structured series of model runs with observations to identify critical overturning processes.

这个协作项目是对海洋热量不稳定的建模研究，及其对南大洋深对流的影响。热物质不稳定性是指海水的可压缩性是压力的非线性功能，因此，较冷，更新鲜的层在温暖的层上可能是静态稳定的，但如果受到干扰，则会变得不稳定。从理论上讲，这是很长一段时间的，但直到最近才被认为是在南大洋中实际发生的作用，特别是对韦德尔海中多尼亚斯（Sea-Ice包装中的可观开放水域）的情节发生的潜在解释。对热生物性对深海对流影响的影响的评估将基于数值大型涡流模拟（LES）模型，该模型能够直接模拟对流羽毛和大规模的海洋流量特征，而大规模的海洋流量特征则可以通过强烈的热型倾覆。基于LES模型的初步结果，并由先前海洋学巡游中观察到的韦德尔海中观察到的条件开始，这项拟议的工作将结合一系列精心构造的模型运行与观察结果，以识别关键的翻转过程。