权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Collaborative Research: Lee Waves and Turbulence Forced by the Kuroshio

合作研究：李波和黑潮引起的湍流

基本信息

批准号：
1829082
负责人：
Ren-Chieh Lien
金额：
$ 189.66万
依托单位：
University of Washington
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2019
资助国家：
美国
起止时间：
2019-01-01 至 2024-09-30
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1829082&HistoricalAwards=false
关键词：
Collaborative Research Lee Waves Turbulence

项目摘要

Roughly 1 TW is input into the ocean circulation by wind-work. How this balanced energy is dissipated to maintain steady state remains uncertain but is important for correctly modeling balanced energy pathways in ocean general circulation models. Loss to lee-wave generation followed by turbulence production has been hypothesized to account for 20-75 percent. The research will clarify lee-wave generation and the waves' role in dissipating vs. redistributing balanced energy. Results from this project will be presented at conferences and published in peer-reviewed journals to make them available to the wider scientific community. Data will be archived at public sites at University of Washington (UW) Applied Physics Laboratory (APL) and Northwest Research Associates. An improved model parameterization for the dissipation and redistribution of balanced flows and induced mixing by lee-wave generation is an expected outcome. The project will support a postdoctoral researcher in data analysis and internal-wave physics. Seattle K-12 classroom visits and active engagement with UW and local science centers is planned. The project will also contribute to the summer program for UW undergraduate students and the annual Pacific Science Center Polar Science Weekend.Lee-wave generation (0.2-0.75 TW) and bottom drag (~0.25 TW) are two hypothesized sinks. The passage of the Kuroshio through Tokara Strait affords an accessible case to evaluate lee-wave generation and dissipation that impact a major western boundary current. It has been assumed that lee-wave generation is lost to turbulence. However, measurements in Antarctic Circumpolar Current jets find that turbulent dissipation rates fall short of predictions by as much as an order of magnitude. Measurements will be made to study internal lee-wave generation and evolution, hydraulic jumps, turbulence and water-mass transformation where the Kuroshio crosses a seamount chain in Tokara Strait. Line-arrays of chi-augmented EMAPEX profiling floats will be deployed at across-stream locations upstream of the seamount chain to be swept across by the Kuroshio, obtaining along-stream/depth sections from the surface to the bottom ( 600 m depth), and from up- to downstream of the shoal topography with a focus on the flow structure and turbulence in the lee. These measurements will address whether lee-wave generation and bottom drag represent major sinks for balanced flows. These measurements will offer a more complete assessment of lee-wave generation and the fate of lee waves than has hitherto been performed.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

大约1TW通过风力输入到海洋环流中。这种平衡能量如何消散以维持稳定状态仍然是不确定的，但对于在海洋环流模式中正确地模拟平衡能量路径是重要的。据推测，背风波产生和湍流产生造成的损失占20%-75%。这项研究将阐明背风波的产生以及波浪在消散和重新分配平衡能量方面的作用。该项目的成果将在会议上公布，并在同行评议的期刊上发表，以便向更广泛的科学界提供这些成果。数据将在华盛顿大学(UW)、应用物理实验室(APL)和西北研究协会的公共网站上存档。对于平衡流动的耗散和再分布以及由背风波产生的混合，改进的模式参数化是一个预期的结果。该项目将支持一名数据分析和内波物理学的博士后研究人员。计划对西雅图K-12学校进行课堂访问，并与威斯康星州大学和当地科学中心积极接触。该项目还将为威斯康星州大学本科生的暑期计划和每年一度的太平洋科学中心极地科学周刊做出贡献。背风波产生(0.2-0.75TW)和底部阻力(~0.25TW)是两个假设的汇。黑潮通过托卡拉海峡为评估影响主要西部边界流的背风波的产生和消散提供了一个容易获得的案例。人们一直认为，背风波的产生是在湍流的作用下消失的。然而，对南极绕极水流的测量发现，湍流的消散率比预测的要低一个数量级。将进行测量，以研究黑潮穿过托卡拉海峡海山链时的内部背风波的产生和演变、水力跳跃、湍流和水团转化。加装CHI的EMAPEX剖面浮标的线阵将布设在海山链上游的横跨位置，以供黑潮横扫，获得从水面到底部(600米深)以及从浅滩地形的上游到下游的顺流/深度剖面，重点放在背风区的流动结构和湍流。这些测量将解决背风波的产生和底部阻力是否代表平衡流动的主要汇。这些测量将提供比迄今为止更全面的对背风波产生和背风波命运的评估。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。