Collaborative Research: Overturning in the Subpolar North Atlantic - Labrador Basin and Floats

合作研究：北大西洋副极地的翻转——拉布拉多盆地和浮体

• 批准号: 2017522
• 负责人: Susan Lozier
• 金额: $ 50.87万
• 依托单位: Georgia Tech Research Corporation
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-10-01 至 2023-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2017522&HistoricalAwards=false
• 关键词: Collaborative; Research; Overturning; Subpolar; North

Variability in the transport of heat, freshwater and mass in the North Atlantic has been linked to a number of societally relevant factors including sea level change, the melting of sea and glacial ice, and anthropogenic carbon storage in the deep ocean. However, the current understanding of the drivers of such changes is limited, making an investigation of overturning in the Sub-polar region a key ocean research priority. This field program explicitly addresses this gap. Furthermore, by engaging the larger international community studying the North Atlantic, Overturning in the Sub-polar North Atlantic Program (OSNAP) is playing a key role in catalyzing scientific progress by promoting international collaborations, synthesis, and the sharing of resources and by training future generations. Key to the latter is a network of early career scientists whose professional growth will continue to be facilitated through targeted activities that have been tested and improved during OSNAP's initial phase. Graduate students and post-docs will be trained in seagoing operations and in the processing and analysis of observational data.The overall goal of this field project, in conjunction with other measurements in the North Atlantic, is to establish determination of the linkage between intermediate and deep water formation and the overturning circulation--a connection that is present in climate models, but has yet to be observed. This project will also provide the first comprehensive view of spreading pathways for the deep waters in the Sub-polar basin. Starting in 2014, the US-led international project, Overturning in the Sub-polar North Atlantic Program (OSNAP), provides a continuous record of the full-water column, trans-basin fluxes of heat, mass and freshwater in the Sub-polar North Atlantic, in partnership with the UK, Netherlands, Canada, Germany and China. Data from the first 21 months of the full OSNAP observing system has been used to produce an initial time series of the meridional overturning, heat and freshwater fluxes for the Sub-polar basin. These preliminary results reveal a highly variable overturning in the basin, interior pathways for overflow waters, surprisingly energetic boundary current systems on timescales from days to months, and a strong overflow plume in the Iceland Basin. The additional two years of OSNAP observations will cover a time frame sufficient to make comparisons with other overturning time series and optimize the OSNAP measurement system--all necessary tasks prior to a request for longer term measurements. This component of OSNAP (OSNAP West) is for the western array across the Labrador Sea between Greenland and Canada in coordination with Germany and Canada. The sub-goal for OSNAP is to quantify the structure and transport of the West Greenland boundary current system and determine the nature of its variability and shelf-slope exchange. In addition, the overflow water pathways throughout the subpolar region and the mechanisms responsible for their variability will be studied by analyzing the subsurface float data collected since 2014 and the output of high-resolution ocean circulation models.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.

北大西洋热量、淡水和质量输送的变化与许多社会相关因素有关，包括海平面变化、海洋和冰川融化以及深海中的人为碳储存。然而，目前对此类变化驱动因素的了解有限，因此对次极地地区倾覆的调查成为海洋研究的重点。该实地计划明确解决了这一差距。此外，通过让更多的国际社会参与北大西洋研究，副极地北大西洋翻转计划（OSNAP）通过促进国际合作、综合和资源共享以及培训未来，在促进科学进步方面发挥着关键作用。几代人。后者的关键是一个由早期职业科学家组成的网络，他们的专业成长将继续通过在 OSNAP 初始阶段经过测试和改进的有针对性的活动来促进。研究生和博士后将接受航海操作以及观测数据处理和分析方面的培训。该实地项目的总体目标是与北大西洋的其他测量相结合，确定中间和数据之间的联系。深水形成和翻转环流——气候模型中存在这种联系，但尚未观察到。该项目还将首次提供副极地盆地深水扩散路径的全面视图。从2014年开始，美国主导的国际项目“副极地北大西洋翻转计划”（OSNAP）提供了副极地全水柱、跨流域热量、质量和淡水通量的连续记录。北大西洋，与英国、荷兰、加拿大、德国和中国合作。完整 OSNAP 观测系统前 21 个月的数据已用于生成副极地盆地经向翻转、热量和淡水通量的初始时间序列。这些初步结果揭示了盆地中高度可变的翻转、溢流水的内部通道、在几天到几个月的时间尺度上令人惊讶的高能边界流系统，以及冰岛盆地中强烈的溢流羽流。额外两年的 OSNAP 观测将涵盖足够的时间范围，以便与其他翻转时间序列进行比较并优化 OSNAP 测量系统——这是在请求进行长期测量之前的所有必要任务。 OSNAP（OSNAP West）的这一组成部分是与德国和加拿大协调，在格陵兰岛和加拿大之间横跨拉布拉多海的西部阵列。 OSNAP 的子目标是量化西格陵兰边界流系统的结构和输送，并确定其变化和陆架坡度交换的性质。此外，还将通过分析自 2014 年以来收集的地下浮标数据和高分辨率海洋环流模型的输出，研究整个副极地地区的溢流水路径及其变化机制。该奖项反映了 NSF 的法定使命，并已被通过使用基金会的智力优点和更广泛的影响审查标准进行评估，认为值得支持。

项目成果

Local and Downstream Relationships between Labrador Sea Water Volume and North Atlantic Meridional Overturning Circulation Variability

当地和下游拉布拉多海水量与北大西洋经向翻转环流变化的关系

• DOI: 10.1175/jcli-d-18-0735.1
• 发表时间: 2019-06-11
• 期刊: Journal of Climate
• 影响因子: 4.9
• 作者: Feili Li;M. Lozier;G. Danabasoglu;N. P. Holliday;Young‐Oh Kwon;A. Romanou;S. Yeager;Rong‐Hua Zhang
• 通讯作者: Rong‐Hua Zhang