大西洋南部翻转循环在整个全新世纪的低变性
Lukas Gerber1, Jörg Lippold2, Finn Süfke2
1Institute of Earth Sciences, Heidelberg University, Heidelberg, Germany. lukas.gerber@geow.uni-heidelberg.de.
Nature communications
|July 22, 2025
概括
大西洋南部翻转循环 (AMOC) 由于融水脉冲,在早期的全新纪期间显著减弱. 后来AMOC的强度稳定下来,但目前的气候变化可能会导致前所未有的减速.
科学领域:
- 古气候学 古气候学
- 海洋学 海洋学 海洋学
- 气候科学 气候科学
背景情况:
- 大西洋南部翻转循环 (AMOC) 显著影响全球气候.
- 尽管有证据表明大规模的冰川时代变化,但Holocene AMOC变异的了解很少.
研究的目的:
- 使用沉积物记录重建全新世AMOC强度.
- 为了研究融水脉冲与AMOC行为之间的关系.
主要方法:
- 使用沉积物231Pa/230Th的比率量化了北大西洋深层向强度.
- 利用Bern3D地球系统模型进行千年分辨率流速估计.
主要成果:
- AMOC在早期Holocene中恢复,但在9.2-8 ka BP之间减弱,与北大西洋融水事件相吻合.
- 在工业化前的时期,AMOC强度从6.5 ka BP开始稳定,达到~18 Sv.
结论:
- 全新世AMOC经历了与融水脉冲相关的显著减弱.
- 目前的人为气候变化可能会导致AMOC减缓,在全新纪中是无与伦比的.
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