Collaborative Research: Completing a 10-Year Record of Deep Western Boundary Current Observations at Line W: A Contribution to the Atlantic Meridional Overturning Circulation Study

概述：在过去的十年里，越来越多的国际研究工作将注意力集中在大西洋经向翻转环流（AMOC）的物理状态上，包括其对气候至关重要的热量、质量和示踪剂的传输，以及其变化的原因和后果。从2004年开始，W线计划-沿着新英格兰和百慕大之间的高度计轨迹对赤道向流动的深西部边界流（DWBC）和极向流动的墨西哥湾流进行系泊和船上测量，获得了AMOC这一分量的显著10年时间序列。该项目的目标是进行最后一次W线巡航，以恢复目前在水中的海流计阵列，并重新占用水文部分，处理恢复的传感器数据，以最终形成并重新整理航海设备，并与AMOC研究人员一起完成对W线数据集的科学分析。由几个AMOC程序生成的属性和运输时间序列现在接近或超过十年的长度，并开始提供真正前所未有的AMOC的结构，强度和可变性的视图。综合这些结果，并将其与状态估计模型相结合，无疑将导致更好地理解的力学，动力学和AMOC可变性的影响。该项目分析工作的重点包括仔细量化W线的局部变化，估计净（海岸到海岸）通过将W线观测与近岸海洋数据相结合并通过模型，并通过对比Line-1000和Line-1000，研究了水属性异常与AMOC波动的相关性。更广泛的影响：麻省理工学院/WHOI联合项目的一名研究生将获得资助，完成她的博士学位。论文将基于W线。与往年一样，一些学生和/或博士后将参与最后的W线巡航，以获得水文取样程序和物理海洋学系泊工作的实践经验。在这个分析和综合项目中，原来的W线研究人员正在吸引一位新的初级科学家参与研究工作。这将向研究者介绍新的观察实践和相关的数据简化和分析程序，同时为研究带来新的专业知识和观点。年轻的研究人员完全精通现代观测方法对观测物理海洋学绝对至关重要。此外，该项目的调查人员将继续在公共宣传活动中展示W线，作为海洋科学和气候变化研究的示范。除了这些人为因素之外，W线项目还将继续作为几种新兴海洋测量技术和相关数据处理程序的试验平台。

Overview: Over the last decade, a growing international research effort has focused attention on the physical state of the Atlantic Meridional Overturning Circulation (AMOC), including its climatically-vital transports of heat, mass and tracers, and the causes and consequences of its variability. Begun in 2004, the Line W program - moored and shipboard measurements of the equatorward-flowing Deep Western Boundary Current (DWBC) and poleward-flowing Gulf Stream along an altimeter track between New England and Bermuda has acquired a remarkable 10-year time series of this component of the AMOC. The goals of this project are to conduct a final Line W cruise to recover the current meter array presently in the water and reoccupy the hydrographic section, to process the recovered sensor data to final form and refurbish the sea-going equipment, and to complete the scientific analysis of the Line W data set in conjunction with fellow AMOC investigators.Intellectual Merit: Property and transport time series generated by several AMOC programs are now approaching or exceeding a decade in length and are starting to provide truly unprecedented views of the AMOC's structure, strength and variability. Synthesizing these results and combining them with state estimate models will undoubtedly result in improved understanding of the mechanics, dynamics and impacts of AMOC variability. Key foci of this project's analysis effort include careful quantification of the local variability at Line W, estimating variations in net (coast-to-coast) meridional transport of selected water masses by combining Line W observations with interior-ocean data and via models, and investigating the meridional coherence of water property anomalies and AMOC fluctuations by comparing Line-W observations with water property observations and AMOC estimates at other latitudes.Broader Impacts: A graduate student in the MIT/WHOI Joint Program will be funded to complete her Ph.D. thesis that will be based on Line W. As in past years, several students and/or postdocs will be involved in the final Line W cruise to gain hands-on experience with hydrographic sampling procedures and physical oceanographic mooring work. In this analysis and synthesis project, the original Line W investigators are entraining a new junior scientist into the research effort. This will introduce the investigator to new observational practices and associated data reduction and analysis procedures while bringing new expertise and viewpoints to the study. It is absolutely critical to observational physical oceanography that young investigators become fully versed in modern observational methods. The project's investigators will additionally continue to showcase Line W in public outreach events as a demonstration of ocean science and climate variation studies. Beyond these human elements, the Line W program is continuing to serve as a testbed for several emerging ocean measurement technologies and associated data processing procedures.