强烈的冰岛-苏格兰溢出水开始于360万年前
Matthias Sinnesael1,2, Boris-Theofanis Karatsolis3,4, Paul N Pearson5
1IMCCE, Observatoire de Paris, 77 avenue Denfert-Rochereau, Paris, France. sinnesam@tcd.ie.
Nature communications
|May 9, 2025
概括
这项研究揭示了北大西洋深水 (NADW) 组成部分的不同起源. 冰岛-苏格兰溢流水在360万年前加速增长,而丹麦海峡溢流水自中新世纪晚期以来一直持续存在.
科学领域:
- 古海洋学是古海洋学.
- 海洋学 海洋学 海洋学
- 气候科学 气候科学
背景情况:
- 北大西洋深水 (NADW) 是大西洋南部翻转循环 (AMOC) 的关键组成部分,影响全球气候.
- 对NADW的源成分的长期演变及其与过去气候事件的关系仍然不太清楚.
- 格陵兰岛和雷克雅纳斯山脊附近的明显的轮漂移系统与现代的NADW组件有关.
研究的目的:
- 使用沉积物记录重建NADW源组件的早期历史.
- 调查冰岛-苏格兰溢流水和丹麦海峡溢流水的时间和演变.
- 评估NADW进化与主要气候事件,如北半球冷却之间的关系.
主要方法:
- 来自国际海洋发现计划 (IODP) 探险395C和395号探险队的沉积芯分析.
- 沉积层的年代测定,以确定漂移沉积的时间表.
- 解释沉积物学数据以推断海洋学条件和水质演变.
主要成果:
- 与冰岛-苏格兰溢流水相关的漂移沉积的快速加速发生在360万年前 (Ma).
- 丹麦海峡溢流水,养埃里克漂流,自中新世纪晚期以来一直是一个持久的特征.
- 对于两个主要的NADW组件,确定了对比的独立历史.
结论:
- 这些发现提供了数百万年时间尺度上的NADW组件演变的直接记录.
- NADW组件的独特历史提供了对过去气候动态中各自角色的见解.
- 冰岛-苏格兰溢流水在3.6亿年前的加速与北半球显著的冷却事件相关.
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