Deep ocean mixing and circulation in subpolar seas

副极地海洋的深海混合和环流

• 批准号: 0926407
• 负责人: Peter Rhines
• 金额: $ 51.41万
• 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: 2009
• 资助国家: 美国
• 起止时间: 2009-08-15 至 2012-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0926407&HistoricalAwards=false
• 关键词: Deep; ocean; mixing; circulation; subpolar

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).This project is an experimental investigation of oceanic circulation and mixing, particularly focused on the deep ocean at high latitude. Using several new technologies recently developed in the Geophysical Fluid Dynamics (GFD) laboratory at University of Washington the Principal Investigator propose to study the stratified, rotating circulations of the high latitude oceans, particularly aiming at mixing effects, topographic effects and the communication of dense overflow circulations with the surrounding ocean. This work will access a unique data-set from a related NSF-funded field program in the Labrador-Greenland-Iceland-Norway sector of the sub-polar Atlantic Ocean. The predicted decline of the global oceanic overturning circulation, in climate model scenarios, is sensitive to parameterized physics of high-latitude circulation and mixing. The sinking of dense plumes occurs with complex topographic ridges, passages, and basins which are extremely difficult to model numerically. As dense water spills from the Faroe-Bank Channel into the Atlantic for example, intense mixing, entrainment and variability have been recently observed. Over a space of 100 km the water mass is diluted and its place in the global general circulation is greatly altered. Specific experiments, motivated by these observations, will be conducted: (i) pathways and instability of deep, dense boundary currents in topographically complex basins;(ii) mixing and entrainment in deep currents, together with two speculative experiments:(iii) circulation and mixing at the polar front(iv) interaction of internal waves with velocity and density fronts.Intellectual Merit: Research in climate dominantly involves by observations and numerical models. Laboratory experiments in this area are rare, yet we believe there are many reasons for experimenting with real fluids: both in the micro-physics embedded in climate models (like phase change and its effect on dynamics, and turbulent mixing), and in simulation of complex three-dimensional circulations of rotating stratified fluids with complex topography. Beyond climate research, this work on basic potential vorticity dynamics helps in understanding circulations of the atmosphere, and the atmospheres of other planets.Broader impacts: Understanding the ocean climate system is of importance to the larger problem of global warming and its predicted effect in slowing the global ocean circulation. The laboratory has been a source of inspiration for students in our field, for young undergraduates studying the global environment and, through open lectures, to the general public. The University of Washington GFD laboratory is constantly in use as a teaching tool, and is regularly a site of filming science segments for television productions. The project involves several international collaborations: (a) with Professor Afanasyev of Memorial Univ., Newfoundland, Canada on the application of 'optical altimetry' and optical thickness techniques in mapping barotropic and baroclinic circulations in the proposed experiments; (b, with GFD l experiments on downslope flows (Dr. E. Darelius of Univ. Bergen, Norway), dense plumes in valleys like the Faroe Bank Channel, and (c) with GFD laboratory experiments of Dr. O-A. Nøst of Tromsø, Norway, on the pathways of deep circulation in high-latitude basins.This project is contribution to the Atlantic Meridional Overturning Circulation theme of the US CLIVAR (CLImate VARiability and predictability) program.

该奖项是根据2009年的《美国回收与再投资法》（公法111-5）资助的。该项目是对海洋循环和混合的实验投资，尤其是针对高纬度的深海。使用最近在华盛顿大学的地球物理动力学（GFD）实验室中开发的几种新技术，主要研究者的建议旨在研究高纬度海洋的分层，旋转的圆圈，尤其是旨在旨在混合效应，地形效应和密集溢出循环与周围洋洋的密集溢出。这项工作将访问来自亚极大海洋亚线大西洋的拉布拉多 - 格林兰德市 - 北诺威领域的相关NSF资助的现场计划的独特数据集。在气候模型方案中，全球大洋倾覆的循环的预测下降对高纬度循环和混合的参数化物理敏感。密集羽流的下沉是在复杂的地形脊，通道和低音中发生的，这些脊是非常困难的建模。例如，最近观察到，最近观察到了浓烈的混合，入口和可变性，因为浓密的水溢出到大西洋。在100公里的空间中，水质量被稀释，其在全球一般循环中的位置发生了很大的改变。将进行这些观察结果的特定实验：（i）地形复杂的低音中深，密集的边界电流的途径和不稳定性； （ii）在深水中混合和入口，以及两个投机实验：（iii）在极前（IV）内波的循环和混合与速度和密度前线的相互作用（IV）相互作用。智能优点：气候中的研究主要参与观察和数值模型。该领域的实验室实验很少见，但是我们认为有许多原因可以实验真实流体：在气候模型中嵌入的微型物理（例如相变及其对动力学的效果以及湍流混合），以及模拟复杂的三维旋转分层流体的复杂三维循环循环循环流体。除了气候研究之外，这项关于基本潜在涡度动态的工作有助于理解大气的循环以及其他行星的气氛。BROADER的影响：了解海洋气候系统对于全球变暖的更大问题及其在减慢全球海洋循环方面的预测影响至关重要。该实验室一直是我们领域的学生，年轻的本科生学习全球环境以及通过公开讲座的年轻本科生的灵感来源。华盛顿大学GFD实验室经常用作教学工具，并且经常是拍摄电视节目科学领域的网站。该项目涉及多个国际合作：（a）与加拿大纽芬兰纪念大学的阿法纳西夫教授一起，在拟议的实验中应用“光学高度学”和光学厚度技术的应用； （b，在下坡流动上进行了GFD L实验（挪威大学卑尔根的E. Darelius博士），诸如Faroe Bank频道等山谷中的密集羽流，以及（c）与O-A。nøst博士的GFD实验室实验，挪威，Tromsø，Troms从Tromes of Tromess of Tromistion contriountion Project at the Issportion contrantion project at the Issis project the Issis projection。美国Clivar（气候可变性和可预测性）计划的主题。