CAREER: Fluxes and Structures in Double-Diffusive Convection

职业：双扩散对流中的通量和结构

• 批准号: 0547650
• 负责人: Timour Radko
• 金额: $ 53.91万
• 依托单位: Naval Postgraduate School
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-03-01 至 2012-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0547650&HistoricalAwards=false
• 关键词: CAREER; Fluxes; Structures; Double; Diffusive

The significance of double-diffuse mixing for water-mass transformation and determining the structure of the temperature-salinity relationship in all oceans is becoming increasingly clear over the last few years. One of the most intriguing aspects of double-diffuse convection is related to its ability to transform smooth vertical gradients into the stepped structures consisting of mixed layers separated by thin stratified interfaces. Recent field data from the tropical Atlantic has shown that vertical fluxes due to salt fingers within thermohaline staircases are significant (by order of magnitude) enhanced over non-staircase regions with similar stratifications. (Schmitt et al., 2005). Thus, it is vital to improve our understanding of the thermohaline staircase formation, evolution and the large scale consequences. In this CAREER award, a researcher at the Naval Postgraduate School will quantify the double-diffusive transport in both smooth gradients and thermohaline staircases, developing a clearer insight into the origin of staircases and specifying the conditions for their information. The work will involve a combination of numerical process modeling and theoretical analysis. Inferences from the theory and model runs will be used to interpret the oceanic fine-and microstructure data and results of the laboratory experiments. The results from this study will resolve the controversy with regard to the dynamics of the thermohaline staircases, the magnitude of the heat and salt mixing rates, and their variation with environmental parameters. The newly developed theory by the principle investigator will invoke the thickness of the mixed layers and the resulting diapycnal fluxes, will be explored. In addition to the intellectual merit of the work, the proposed teaching activities will target the Naval Postgraduate School students and expose them to the physics of the ocean microstructure by developing a special topics course, expanding the distance learning program, and advising several graduate students.

在过去的几年中，双扩散混合对水质量转化和确定温度 - 含量关系的结构的重要性越来越清晰。 双扩散对流的最有趣的方面之一与其将平滑垂直梯度转化为由薄层界面分离的混合层组成的阶梯结构的能力有关。 来自热带大西洋的最新田间数据表明，由于具有相似分层的非楼梯区域，由于热盐层中盐指引起的垂直通量（按数量级）增强了。 （Schmitt等，2005）。因此，提高我们对热盐楼梯形成，进化和大规模后果的理解至关重要。 在该职业奖中，海军研究生院的一名研究人员将量化平稳梯度和热盐楼梯的双层运输，从而对楼梯的起源进行更清晰的见解，并为其信息指定条件。 这项工作将涉及数值过程建模和理论分析的组合。 理论和模型运行的推论将用于解释海洋精细的微观结构数据以及实验室实验的结果。 这项研究的结果将解决有关热盐层的动力学，热量和盐混合速率的大小以及与环境参数的变化的争议。 原理研究者新开发的理论将调用混合层的厚度，并将探索由此产生的Diapynal通量。 除了工作的智力优点外，拟议的教学活动还将针对海军研究生的学生，并通过开发特殊主题课程，扩大远程学习计划并为几位研究生提供建议，使他们接触到海洋微观结构的物理学。