近日，瑞士洛桑大学Patrick Blaser团队研究了末次盛冰期与海因里希冰期1期间盛行的北大西洋深层水。2025年5月6日出版的《自然—地球科学》杂志发表了这项成果。
深海环流通过对碳循环和能量分布的反馈来调节冰川间冰期气候。过去的研究表明，冰川时期通风良好的北大西洋深水的收缩促进了深海中的碳储存和大气二氧化碳水平的下降。然而，不同水团的空间范围和性质仍然不确定，部分原因是古海洋学替代重建存在冲突。
研究组结合了五个独立的代理指标，以提高可信度，重建末次冰期（约2.1万年前）和随后的海因里希·斯塔迪亚尔1期期间的大西洋深水分布——当时北大西洋的大规模漂流干扰了深水形成，并导致了全球气候变化。结果发现，北大西洋深水在这两个时期都很普遍，尽管它的性质从寒冷、通风良好的模式转变为通风较差、可能更温暖的模式。这一发现意味着在这些冷边界条件下，深水形成具有显著的持续性，这得益于两种形成模式之间的补偿。该约束为评估地球系统模型提供了一个重要的基准，这可以增强对未来气候预测的信心。
附：英文原文
Title: Prevalent North Atlantic Deep Water during the Last Glacial Maximum and Heinrich Stadial 1
Author: Blaser, Patrick, Waelbroeck, Claire, Thornalley, David J. R., Lippold, Jrg, Pppelmeier, Frerk, Kaboth-Bahr, Stefanie, Repschlger, Janne, Jaccard, Samuel L.
Issue&Volume: 2025-05-06
Abstract: Deep ocean circulation modulated glacial–interglacial climates through feedbacks to the carbon cycle and energy distribution. Past work has suggested that contraction of well-ventilated North Atlantic Deep Water during glacial times facilitated carbon storage in the deep ocean and drawdown of atmospheric CO2 levels. However, the spatial extent and properties of different water masses remain uncertain, in part due to conflicting palaeoceanographic proxy reconstructions. Here we combine five independent proxies to increase confidence and reconstruct Atlantic deep water distributions during the Last Glacial Maximum (around 21 thousand years ago) and the following Heinrich Stadial 1—a time when massive ice rafting in the North Atlantic interfered with deep water formation and caused global climate shifts. We find that North Atlantic Deep Water remained widespread in both periods, although its properties shifted from a cold, well-ventilated mode to a less-ventilated, possibly warmer, mode. This finding implies a remarkable persistence of deep water formation under these cold boundary conditions, sustained by compensation between the two formation modes. Our constraints provide an important benchmark for evaluating Earth system models, which can enhance confidence in future climate projections.
DOI: 10.1038/s41561-025-01685-5
Source: https://www.nature.com/articles/s41561-025-01685-5