The Northwestern North Atlantic: a Retrospective Analysis of Observations from the CV Oleander on the Shelf and Slope

北大西洋西北部：CV Oleander 在陆架和斜坡上观测的回顾性分析

• 批准号: 1634094
• 负责人: Magdalena Andres
• 金额: $ 47.79万
• 依托单位: Woods Hole Oceanographic Institution
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-01 至 2020-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1634094&HistoricalAwards=false
• 关键词: Northwestern; North; Atlantic; Retrospective; Analysis

This study examines the long-term variability in the northwestern North Atlantic over the continental shelf and slope using long-duration observations collected by a ship of opportunity and output from a regional high-resolution numerical model. This area has been highlighted as a hotspot of sea level rise and ocean warming with the trends superimposed on strong interannual to decadal variability. This study will investigate the processes driving the low-frequency variability of shelf temperature and sea level, with a focus on the physical mechanisms underlying the recent changes. The project also includes the development of observation-based coastal temperature indexes from profiles collected by the CV Oleander, a commercial vessel that operates weekly round-trip transits between New Jersey and Bermuda, and investigation of potential predictors of interannual variability of these temperature indexes relating to sea level and atmospheric pressure. The processes to be studied have important implications for both climate and commercial fisheries. Results will be presented in both climate and continental shelf workshops. The PIs will provide the data products derived from the observations to the science community via existing Oleander Program websites. The PIs will also continue public communication and outreach efforts including visits to a local 8th grade classroom, building on a long-term outreach effort with the middle school science teacher and outreach directed to commercial fishermen through the Commercial Fisheries Research Foundation in Rhode Island, which has strong links to Woods Hole Oceanographic Institution. This project will support and train a graduate student who has already published a peer-reviewed paper on this data set.The temperature sections (spanning 37 years) and velocity sections (spanning 22 years) have been collected with expendable bathythermographs (XBTs) and a shipboard acoustic Doppler current profiler (ADCP) via the CV Oleander. This data set is unique in terms of its high resolution, extended duration over multiple decades, and co-located temperature and velocity observations. Temperature data collected by the CV Oleander can resolve the interannual to decadal signals embedded in the region's annual cycle. Further, the exceptional duration of the temperature records amassed along a constant ship route, and their combination with velocity and surface salinity measurements from the ship and complementary data sets (e.g., satellite altimetry, reanalysis winds, and tide gauge data) will allow this study to characterize the variability and to explore mechanisms driving the changes such as shifts in Gulf Stream position, changes in large scale wind forcing, and changes in along-shelf advection. The study will also capitalize on existing output from a high-resolution numerical model that captures variability in the region with fidelity. This region has been identified as having a very high rate of ocean warming relative to the global mean rate. Variability in this region links open-ocean phenomena (Gulf Stream, Deep Western Boundary Current, and Atlantic Meridional Overturning Circulation, AMOC) to shelf phenomena (Middle Atlantic Bight shelf circulation, shelfbreak jet dynamics, and ecosystem dynamics).

这项研究探讨了长期变化，在北大西洋西北部的大陆架和斜坡使用长期观测收集的机会和输出的一艘区域高分辨率数值模式。这一地区已被强调为海平面上升和海洋变暖的热点，其趋势叠加在强烈的年际至十年变化上。这项研究将调查驱动大陆架温度和海平面低频变化的过程，重点是最近变化的物理机制。该项目还包括根据CV Oleander号收集的剖面图制定基于观测的沿海温度指数，CV Oleander号是一艘每周往返于新泽西和百慕大之间的商业船只，并调查与海平面和大气压力有关的这些温度指数年际变化的潜在预测因素。有待研究的过程对气候和商业渔业都有重要影响。结果将在气候和大陆架研讨会上介绍。PI将通过现有的夹竹桃计划网站向科学界提供从观测中获得的数据产品。PI还将继续公共沟通和外展工作，包括访问当地8年级的教室，建立在与中学科学教师的长期外展工作和通过罗得岛的商业渔业研究基金会向商业渔民进行外展的基础上，该基金会与伍兹霍尔海洋研究所有着密切的联系。该项目将支持和培训一名研究生，该研究生已发表了关于这一数据集的同行评审论文，温度剖面（跨度37年）和速度剖面（跨度22年）是通过CV Oleander用一次性深海温度计和船上声学多普勒海流剖面仪收集的。该数据集的独特之处在于其高分辨率，数十年的持续时间，以及共同定位的温度和速度观测。CV夹竹桃收集的温度数据可以解决该地区的年周期中嵌入的年际到十年信号。此外，温度记录的异常持续时间沿着沿着恒定的船舶路线积累，并且它们与来自船舶的速度和表面盐度测量值以及补充数据集（例如，卫星测高、再分析风和验潮仪数据）将使这项研究能够描述变化的特征，并探索驱动变化的机制，如墨西哥湾流位置的变化、大尺度风强迫的变化和沿大陆架平流的变化。这项研究还将利用一个高分辨率数值模型的现有产出，该模型逼真地捕捉了该区域的变异性。该区域已被确定为相对于全球平均速率具有非常高的海洋变暖速率。这一区域的变化将公海现象（墨西哥湾流、深西部边界流和大西洋经向翻转环流）与陆架现象（中大西洋湾陆架环流、陆架断裂急流动力学和生态系统动力学）联系起来。