Thermohaline Interleaving in Baroclinic Frontal Zones

斜压锋区的温盐交错

• 批准号: 0622922
• 负责人: William Smyth
• 金额: $ 59.75万
• 依托单位: Oregon State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-09-15 至 2012-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0622922&HistoricalAwards=false
• 关键词: Thermohaline; Interleaving; Baroclinic; Frontal; Zones

ABSTRACTOCE-0622922Intellectual meritThermohaline interleaving is an important mechanism for the lateral mixing of water masses in virtually every ocean basin. Horizontal diffusivities due to interleaving are often comparable with those due to mesoscale eddies, Theoretical research into thermohaline interleaving faces two important obstacles: (1) the need to accurately parameterize microscale mixing processes, including salt fingering, diffusive convection, convective overturning and shear-driven turbulence, and (2) the mathematical challenge of including baroclinic effects in linear and nonlinear theories. In this project, a coordinated sequence of linear and nonlinear theoretical analyses will address both of these problems. The linear stability analysis will delimit the parameter range in which oblique modes can be ignored. Preliminary results indicate that this range covers essentially all ocean regimes except near boundaries. The one-dimensional nonlinear modeling of cross-front modes will extend to the final equilibrium state. The direct numerical simulations will extend these results into the regime of three-dimensional nonlinear interleaving. At every stage, results will be compared with existing observational data. Broader impactsThe proposed research is a significant step toward the development of parameterizations of frontal exchange due to thermohaline interleaving in basin and global-scale models. It will also provide a test bed for mixing parameterizations that can be used in a wider class of models. A graduate student will receive training in state of the art theoretical and numerical techniques and an international collaboration will be fostered.

Abstractoce-0622922Intlectual firitthermohaline交织是几乎每个海洋盆地水肿块横向混合的重要机制。由于中尺度涡流而引起的水平扩散通常与嗜热盐交织的理论研究相媲美，这两个重要障碍是：（1）需要准确地参数化显微镜混合过程，包括盐指法，包括对流的对流，对流式挑战和触发性的挑战，包括纽带和剪切驱动的驱动和（2），以及2）非线性理论。在这个项目中，线性和非线性理论分析的协调序列将解决这两个问题。线性稳定性分析将界定可以忽略倾斜模式的参数范围。初步结果表明，此范围基本上涵盖了除近边界以外的所有海洋制度。跨前期模式的一维非线性建模将延伸至最终平衡状态。直接的数值模拟将将这些结果扩展到三维非线性交织的状态。在每个阶段，结果都将与现有的观察数据进行比较。更广泛的影响拟议的研究是朝着盆地和全球尺度模型中的热鞘中断引起的额叶交换参数化的重要一步。它还将提供一个测试床，用于混合参数化，可以在更广泛的型号中使用。研究生将接受最先进的理论和数值技术的培训，并将培养国际合作。