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：在过去十年中，越来越多的国际研究工作将注意力集中在大西洋子午线翻转环流(AMOC)的物理状态上，包括其对气候至关重要的热量、质量和示踪剂输送，以及其变异性的原因和后果。从2004年开始，W线计划对沿新英格兰和百慕大之间的高度计轨道的赤道流向的深西部边界流(DWBC)和流向极地的墨西哥湾流进行系泊和船上测量，获得了AMOC这一组成部分的惊人的10年时间序列。该项目的目标是进行最终的W线巡航，以恢复目前在水中的海流计阵列并重新利用水文部分，处理恢复的传感器数据以最终形成并翻新出海设备，并与AMOC的其他研究人员一起完成对W线数据集的科学分析。智力优势：由几个AMOC项目生成的财产和运输时间序列现在长度接近或超过十年，并开始提供对AMOC结构、强度和变异性的真正前所未有的看法。综合这些结果并将它们与状态估计模型结合起来，无疑将有助于更好地理解AMOC变异性的力学、动力学和影响。该项目分析工作的主要重点包括仔细量化W线的局部可变性，通过将W线观测与内海数据和VIA模式相结合来估计选定水团的净(海岸到海岸)经向输送的变化，并通过将W线观测与其他纬度的水属性观测和AMOC估计进行比较来调查水属性异常和AMOC波动的经向一致性。广泛影响：麻省理工学院/WHOI联合项目的一名研究生将获得资助，以完成她将基于W线的博士论文。几名学生和/或博士后将参与最后的W线邮轮，以获得水文采样程序和实际海洋系泊工作的实践经验。在这个分析和综合项目中，最初的W线调查人员正在将一名新的初级科学家带入研究工作。这将向研究人员介绍新的观测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。对于观测物理海洋学来说，年轻的研究人员完全精通现代观测方法是绝对关键的。该项目的研究人员还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.