英国气象局J. A. Baker团队发现，即使在极端气候条件下，大西洋环流仍在持续翻转。相关论文发表在2025年2月26日出版的《自然》杂志上。

大西洋经向翻转环流（AMOC）对大西洋向北的热量输送至关重要，预计将因全球变暖而减弱，对全球气候产生重大影响。然而，AMOC减弱的程度尚不确定，气候模型之间存在很大差异，一些统计指标表明即将崩溃。

研究组展示了AMOC在34个气候模型中对极端温室气体和北大西洋淡水强迫的弹性。在持续的南大洋风的驱动下，南大洋的上升在所有情况下都维持着减弱的AMOC，防止其完全崩溃。由于南大洋的上升流必须与大西洋或太平洋的下降流相平衡，因此只有当补偿太平洋经向翻转环流（PMOC）发展时，AMOC才能崩溃。

值得注意的是，几乎所有模型中都出现了PMOC，但它太弱了，无法平衡所有南大洋的上升流，这表明AMOC在本世纪不太可能崩溃。该研究结果揭示了AMOC的稳定机制，对过去和未来的AMOC变化以及生态系统和海洋生物地球化学都有影响。他们认为，迫切需要更好地了解和估计南大洋和印度洋-太平洋环流，以准确预测未来的AMOC变化。

附：英文原文

Title: Continued Atlantic overturning circulation even under climate extremes

Author: Baker, J. A., Bell, M. J., Jackson, L. C., Vallis, G. K., Watson, A. J., Wood, R. A.

Issue&Volume: 2025-02-26

Abstract: The Atlantic Meridional Overturning Circulation (AMOC), vital for northwards heat transport in the Atlantic Ocean, is projected to weaken owing to global warming1, with significant global climate impacts2. However, the extent of AMOC weakening is uncertain with wide variation across climate models1,3,4 and some statistical indicators suggesting an imminent collapse5. Here we show that the AMOC is resilient to extreme greenhouse gas and North Atlantic freshwater forcings across 34 climate models. Upwelling in the Southern Ocean, driven by persistent Southern Ocean winds, sustains a weakened AMOC in all cases, preventing its complete collapse. As Southern Ocean upwelling must be balanced by downwelling in the Atlantic or Pacific, the AMOC can only collapse if a compensating Pacific Meridional Overturning Circulation (PMOC) develops. Remarkably, a PMOC does emerge in almost all models, but it is too weak to balance all of the Southern Ocean upwelling, suggesting that an AMOC collapse is unlikely this century. Our findings reveal AMOC-stabilizing mechanisms with implications for past and future AMOC changes, and hence for ecosystems and ocean biogeochemistry. They suggest that better understanding and estimates of the Southern Ocean and Indo-Pacific circulations are urgently needed to accurately predict future AMOC change.

DOI: 10.1038/s41586-024-08544-0

Source: https://www.nature.com/articles/s41586-024-08544-0