Geochemical response of the mid-depth Northeast Atlantic Ocean to freshwater input during Heinrich events 1 to 4
Geochemical response of the mid-depth Northeast Atlantic Ocean to freshwater input during Heinrich events 1 to 4
复制标题
海因里希事件1至4期间东北大西洋中深度对淡水输入的地球化学响应
DOI：
10.1016/j.quascirev.2016.08.035
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发表时间：
2016
影响因子：
4
通讯作者：
Crocker A
中科院分区：
文献类型：
--
作者：
Crocker A
海因里希事件是指冰川源淡水快速释放到高纬度北大西洋的间隔，打断了晚更新世冰川。在海因里希事件期间，将淡水输送到北大西洋深水形成的主要地点可能会导致大西洋经向翻转环流（AMOC）的重大中断，然而，最近已经证明，响应于每次淡水输入而关闭AMOC的简单概念过于简单化。在这里，我们提出了一个新的多代理数据集，跨越过去41,000年，解决了四个海因里希事件在一个经典的中深度北大西洋钻探现场，采用四个独立的地球化学示踪剂的水团性质：硼/钙，碳和氧同位素有孔虫方解石和钕同位素在多个基板。我们还报告了稀土元素的分布调查的保真度，钕同位素记录在北大西洋东北部的水团分布的变化。我们的数据揭示了不同的地球化学特征，每个海因里希事件，这表明淡水输送和/或输入率的网站至少发挥了同样重要的作用，在冰川周期的阶段，淡水被释放。在过去的41 kyr中，北大西洋东北部的中层从来没有被南方水源的水所主导。相反，我们记录了持续通风的冰川北大西洋中层水（GNAIW），虽然变量属性标志着变化的供应从多个贡献北方来源。
Heinrich events are intervals of rapid iceberg-sourced freshwater release to the high latitude North Atlantic Ocean that punctuate late Pleistocene glacials. Delivery of fresh water to the main North Atlantic sites of deep water formation during Heinrich events may result in major disruption to the Atlantic Meridional Overturning Circulation (AMOC), however, the simple concept of an AMOC shutdown in response to each freshwater input has recently been shown to be overly simplistic. Here we present a new multi-proxy dataset spanning the last 41,000 years that resolves four Heinrich events at a classic mid-depth North Atlantic drill site, employing four independent geochemical tracers of water mass properties: boron/calcium, carbon and oxygen isotopes in foraminiferal calcite and neodymium isotopes in multiple substrates. We also report rare earth element distributions to investigate the fidelity by which neodymium isotopes record changes in water mass distribution in the northeast North Atlantic. Our data reveal distinct geochemical signatures for each Heinrich event, suggesting that the sites of fresh water delivery and/or rates of input played at least as important a role as the stage of the glacial cycle in which the fresh water was released. At no time during the last 41 kyr was the mid-depth northeast North Atlantic dominantly ventilated by southern-sourced water. Instead, we document persistent ventilation by Glacial North Atlantic Intermediate Water (GNAIW), albeit with variable properties signifying changes in supply from multiple contributing northern sources.
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影响因子：
5.3
作者：
T. Stichel;M. Frank;J. Rickli;B. Haley
通讯作者：
T. Stichel;M. Frank;J. Rickli;B. Haley
18-41年前亚极地东北大西洋发生百年至千年规模的冰海相互作用
影响因子：
--
作者：
I. Hall;E. Colmenero;R. Zahn;V. Peck;S. Hemming
通讯作者：
S. Hemming
影响因子：
--
作者：
D. Thornalley;S. Barker;Julia Becker;I. Hall;G. Knorr
通讯作者：
D. Thornalley;S. Barker;Julia Becker;I. Hall;G. Knorr
过去 145 kyrs 期间南大西洋中部深部环流变化反映在 231Pa/230Th、钕同位素和底栖 δ13C 组合记录中
影响因子：
5.3
作者：
L. Jonkers;R. Zahn;Alexander L. Thomas;G. Henderson;W. Abouchami;R. Francois;P. Masqué;I. Hall;T. Bickert
通讯作者：
T. Bickert
工业化前北大西洋的δ13C大梯度被揭示
影响因子：
56.9
作者：
A. Olsen;U. Ninnemann
通讯作者：
U. Ninnemann