Transports and variability-driving mechanisms in Flemish Pass at the western boundary of the subpolar North Atlantic (FLEPVAR)

北大西洋副极地西部边界弗拉芒山口的输运和变异驱动机制 (FLEPVAR)

• 批准号: 206548004
• 负责人: Dr. Kerstin Jochumsen
• 金额: --
• 依托单位: Bundesamt für Seeschifffahrt und Hydrographie (BSH)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2011
• 资助国家: 德国
• 起止时间: 2010-12-31 至 2014-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/206548004?language=en
• 关键词: Transports; variability; driving; mechanisms; Flemish

Labrador Sea Water (LSW) formed in the Labrador Sea constitutes the lightest contribution to North Atlantic Deep Water (NADW), a conglomerate of water masses that form the cold return flow of the Atlantic meridional overturning circulation (MOC). Climate variability can be modulated by changes in the MOC strength; such changes are thought to be linked to variations in LSW formation. The Deep Western Boundary Current (DWBC) is the main southward pathway for newly formed LSW. Topographic obstacles at the southern exit of the Labrador Sea split the DWBC into an upper branch carrying LSW through Flemish Pass (~1200m sill depth) and a branch carrying all NADW components along the continental slope around Flemish Cap. Up to now, transports through Flemish Pass and their contribution to the MOC are still uncertain, the importance of the pass for the export of LSW and its associated variability are yet unknown. In this project the transports through Flemish Pass will be quantified, and mechanisms driving and governing the variability of the flow will be investigated.The project focuses on the following questions: What is the magnitude of transports for waters passingthrough Flemish Pass and their associated variability? Which processes drive the variability? What is the relevance of the deep water export through Flemish Pass for the MOC, especially when compared to the DWBC export? Are both deep water export pathways (through Flemish Pass or around Flemish Cap) coupled? What processes govern the inflow of deep water into Flemish Pass? To answers these questions, ship-based measurements and time series from moored instruments in the Flemish Pass will be analyzed in conjunction with output from two state-of-the-art ocean models run at high-resolution.

拉布拉多海形成的拉布拉多海水(LSW)对北大西洋深水(NADW)的贡献最小，NADW是形成大西洋经向翻转环流(MOC)的冷回流的水团。气候变异性可以通过MOC强度的变化来调节；这种变化被认为与LSW地层的变化有关。深西部边界流(DWBC)是新形成的低纬向流的主要南下通道。拉布拉多海南部出口的地形障碍物将DWBC分成两部分，一部分通过佛兰德山口(约1200米深)运送LSW，另一部分沿着佛兰德海角的大陆斜坡运送所有NADW组件。到目前为止，通过佛兰芒山口的运输及其对交通部的贡献仍然不确定，该山口对LSW出口的重要性及其相关的可变性也尚不清楚。在这个项目中，将量化通过佛兰德山口的运输，并将研究驱动和控制流量变化的机制。该项目集中于以下问题：通过佛兰德山口的水的运输的规模及其相关的变化？是哪些过程驱动了这种可变性？通过佛兰芒山口的深水出口对交通部有什么意义，特别是与DWBC出口相比？这两条深水出口通道(通过佛兰芒山口或佛兰德海角周围)是否相连？是什么过程控制着深水流入佛兰芒山口？为了回答这些问题，将结合两个以高分辨率运行的最先进海洋模型的输出来分析佛兰德山口系泊仪器的船基测量和时间序列。

项目成果

Variability of Labrador Sea Water transported through Flemish Pass during 1993–2013

1993 年至 2013 年期间通过弗拉芒山口输送的拉布拉多海水的变化

• DOI: 10.1002/2015jc010939
• 发表时间: 2013
• 期刊: Journal of Geophysical Research
• 作者: Schneider;D. Kieke;K. Jochumsen;E. Colbourne;I. Yashayaev;R. Steinfeldt;E. Varotsou;N. Serra;M. Rhein
• 通讯作者: M. Rhein

Interannual transport variability of Upper Labrador Sea Water at Flemish Cap

• DOI: 10.1002/2015jc010705
• 发表时间: 2015-07
• 期刊: Journal of Geophysical Research
• 作者: Eirini Varotsou;K. Jochumsen;N. Serra;D. Kieke;L. Schneider