Investigating the Characteristics and Consequences of Interannual Variations in the Northwest Atlantic's Deep Western Boundary Current

0241354工具拟议的研究将加深人们对北大西洋深水向低纬度输出的机制和速度的了解，以及不同的深水流量与上层海洋环流的关系。这一知识将有助于阐明海洋对海-气交换变化的反应，并最终阐明海洋在全球气候变化中的作用。西北大西洋中纬度翻转环流包括墨西哥湾流向极地输送暖水和较冷的中深层水向赤道流动。对于全球电流系统的这些分支及其相关的区域再循环如何在十年时间尺度上变化的理解是不完整的。限制了解进展的是，缺乏长的、分辨率良好的记录来记录关于水性质、分层和深西部边界流(DWBC)系统输送的年际信号。重要的是，在亚极纬度产生的异常可能会被墨西哥湾流深刻地改变甚至阻止。相反，亚极异常可能会影响该气流的位置、强度和/或稳定性，进而影响整个北大西洋的海气交换模式。该项目将通过在伍兹霍尔以南的斜坡上保持一个系泊阵列，并每半年沿着这条线占据一段水文区段，记录其墨西哥湾流交叉底点上游的DWBC的温度、盐度、示踪物和速度的变化。该阵列(为纪念瓦尔·沃辛顿而命名为W站)将量化DWBC水性质、层化(位涡)和输送的变化。这艘船可能进行的高空间分辨率采样将有助于核实该阵列能够分辨年际信号(以及用于岸边示踪剂分析的返回水样)。除了原始观测外，还将制作和分发岩心特性时间序列和水团输送等增值产品。同样重要的是，该项目将探索我们建议的阵列的一个子集是否足以标示这一地区的水性质和输送变化，为建立长期海洋观测系统奠定基础。建议的观测将探索和测试关于深西部边界流和墨西哥湾流相互作用的理论想法。报名参加物理海洋学入门课程的研究生将参加拟议的航海，向他们介绍观测海洋学。此外，该计划将支持一名博士生，他的论文研究将集中在获得的数据上。所有观测结果和产生的数据产品将通过互联网方便地提供给社区，目的是促进这些数据的广泛使用，以便社区的任何成员都可以在他们自己的研究计划中使用这些数据。

0241354 TooleThe proposed study will build understanding of the mechanisms and rates of North Atlantic Deep Water export to lower latitudes and the relationships of varying deep water flow to the upper ocean circulation. This knowledge will help clarify the response of the ocean to variations in air-sea exchange and ultimately, the ocean's role in global climate change. The overturning circulation of the Northwest Atlantic Ocean at mid-latitude involves poleward transport of warm water by the Gulf Stream and equatorward flow of colder intermediate and deep waters. Comprehension of how these limbs of the global current system and their associated regional recirculations vary on decadal time scale is incomplete. Limiting advance in understanding is the lack of long, well-resolved records to document interannual signals in water properties, stratification, and transport of the Deep Western Boundary Current (DWBC) system. Importantly, anomalies created at subpolar latitudes may be profoundly altered or even blocked by the Gulf Stream. Conversely, subpolar anomalies may influence the position, strength, and/or stability of the Stream, and in turn affect patterns of air-sea exchange throughout the North Atlantic. This project will document temperature, salinity, tracer, and velocity variations of the DWBC upstream of its Gulf Stream cross-under point by maintaining a moored array over the slope south of Woods Hole, and occupying a hydrographic section along this line semi-annually. The array (named Station W in memory of Val Worthington) will quantify changes in DWBC water properties, stratification (potential vorticity), and transport. The high-spatial-resolution sampling possible from the ship will help verify that the array resolves interannual signals (as well as return water samples for shoreside tracer analyses). In addition to raw observations, value-added products such as time series of core properties and transport by water mass will be produced and distributed. Equally important, the project will explore whether a subset of our proposed array is su?cient to index water property and transport variations in this area, setting the stage for a long-term ocean observing system.The observations proposed will explore and test theoretical ideas about the interaction of the Deep Western Boundary Current and Gulf Stream. Graduate students enrolled in the introductory physical oceanography course will participate on the proposed cruises, introducing them to observational oceanography. Moreover, the program will support one Ph.D. student whose dissertation research will focus on the acquired data. All observations and resulting data products will be expediently made available to the community via the internet with the intention of fostering widespread use of these data so that any member of the community can utilize them in their own research program.