Collaborative Research: Enhancing our Understanding of North Atlantic Deep Water Pathways using Nonlinear Dynamics Techniques

GSTDTAP

项目编号	1851097
	Collaborative Research: Enhancing our Understanding of North Atlantic Deep Water Pathways using Nonlinear Dynamics Techniques
	Francisco Beron-Vera (Principal Investigator)
主持机构	University of Miami Rosenstiel School of Marine&Atmospheric Sci
项目开始年	2019
	2019-07-15
项目结束日期	2022-06-30
资助机构	US-NSF
项目类别	Standard Grant
项目经费	399576(USD)
国家	美国
语种	英语
英文摘要	For most of the last century, the equatorward spread of cold water masses from high latitudes in the Labrador and Nordic Seas was expected to be largely contained along the Deep Western Boundary Current in the subpolar and subtropical North Atlantic. Since the turn of this century, observational floats launched within these water masses have defied this expectation. Instead, myriad interior pathways have been revealed across the North Atlantic. Contemporaneously, an inventory of anthropogenic carbon dioxide has shown the subpolar North Atlantic to be the most intense (per unit area) sink of all ocean basins, a characteristic attributable to the deep penetration of newly-formed water masses in that basin. While the deep limb of the Atlantic Meridional Overturning Circulation has long been appreciated as a heat and freshwater reservoir, its role as a carbon reservoir is now apparent. Thus, at a time when the conventional understanding of these deep water mass pathways has been upended, there is a stronger reason than ever to understand the spread and fate of these water masses. Over the past decade, simulated float trajectories have augmented the relatively small number of observational floats in the North Atlantic in order to gain a broader understanding of water mass pathways. However, analyses of the observed and modeled trajectories have largely used conventional methods to ascertain a limited number of flow characteristics. This study will capitalize on recent advances in nonlinear dynamics in order to provide a more comprehensive description and understanding of these water masses and flows limited observations. Thus, by using these tools to unravel deep water pathways, this project will aid our understanding of the North Atlantic as a deep carbon reservoir, and thereby have a significant societal impact. Broader impacts with this proposed work also include the training of a postdoctoral researcher to facilitate an independent research career and the training of a physical oceanography student in the use of nonlinear dynamical tools. This project will address a fundamental question in modern physical oceanography through the use of two complementary tools emerging at the interface of nonlinear dynamics and fluid dynamics. Probabilistic tools will be used to cast new light on the transformation and fate of the deep waters through the construction of Lagrangian geographies that constrain connectivity, residence times within water mass provinces, preferred circulation pathways, transit times along these pathways, and transport across province boundaries. Deterministic tools that have recently proven efficient at extracting persistent transport pathways will also be used to delineate preferred transport pathways, and thus will be used to frame deep water routes. This offers a promising fertilization of nonlinear dynamical tools into a traditional physical oceanographic area of study. Specifically, this work will apply dynamical systems tools to: 1) determine the long-term fate and elucidate the preferred pathways of the deep water masses; 2) ascertain the extent to which potential vorticity conservation or other dynamics constrains these pathways; and 3) identify spatial provinces (domains) that define water mass residence and evaluate exchanges among them. The small, but growing number of observational floats, including those recently recovered from the Overturning in the Subpolar North Atlantic Program (OSNAP), as well as Argo data and simulated float trajectories from ocean general circulation models, will be used in this analysis. 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.
文献类型	项目
条目标识符	http://119.78.100.173/C666/handle/2XK7JSWQ/213204
专题	环境与发展全球科技态势
推荐引用方式 GB/T 7714	Francisco Beron-Vera .Collaborative Research: Enhancing our Understanding of North Atlantic Deep Water Pathways using Nonlinear Dynamics Techniques.2019.