在北半球的北太平洋深水形成减少了北半球冰川
Friso de Graaf1,2, Heather L Ford3, Natalie Burls4
1School of Geography, Queen Mary University of London, London, UK. f.m.degraaf@qmul.ac.uk.
Nature communications
|March 20, 2025
概括
在世时期,北太平洋深水 (NPDW) 形成,但在冰川时期下降. 这表明海洋门户对海平面和冰体积变化敏感,影响深水循环和气候.
科学领域:
- 古海洋学是古海洋学.
- 气候科学 气候科学
- 海洋学 海洋学 海洋学
背景情况:
- 北太平洋的深水形成今天不存在,但可能发生在新纪.
- 有证据表明新纪太平洋南部翻转循环存在,但代理数据可能会因生产率而偏见.
- 北太平洋深水 (NPDW) 形成被假设为温暖的平纪晚期.
研究的目的:
- 为了研究平纪北太平洋深水群体和循环.
- 为了重建北太平洋深水 (NPDW) 形成的历史.
- 评估海洋循环对气候和海平面变化的敏感性.
主要方法:
- 从北太平洋产生了一个合的Mg/Ca-δ18O同位素记录.
- 分析的重点是识别在新纪期间不同的水体.
- 重建了NPDW形成的时间和范围.
主要成果:
- 在平纪北太平洋地区发现了两种不同的水体.
- 北太平洋深水 (NPDW) 发现比深水更冷,更新鲜.
- 从大约270万年前开始观察到NPDW形成的下降,特别是在冰川时期.
结论:
- 二世北太平洋循环与现代条件有很大的不同.
- 海洋门户对海平面和冰体积波动有很强的敏感性.
- 深水循环的变化深深地影响了纪气候系统.
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