Gerber Lukas, Lippold Jörg, Süfke Finn, Valk Ole, Testorf Pierre, Ehnis Manuel, Tautenhahn Saskia, Max Lars, Chiessi Cristiano M, Regelous Marcel, Szidat Sönke, Friedrich Oliver, Pöppelmeier Frerk
Institute of Earth Sciences, Heidelberg University, Heidelberg, Germany.
Oeschger Centre for Climate Change Research, University of Bern, Bern, Switzerland.
Nat Commun. 2025 Jul 22;16(1):6748. doi: 10.1038/s41467-025-61793-z.
Earth system models and paleo-reconstructions indicate that shifts in Atlantic Meridional Overturning Circulation (AMOC) strength profoundly impact global climate. While the last glacial termination experienced large AMOC variations, evidence of AMOC changes during the Holocene are poorly constrained. Here we present a Holocene AMOC reconstruction by quantifying mean bottom water advection strength in the deep North Atlantic. For this, we estimated volumetric flow rates from sedimentary Pa/Th records with millennial resolution using the Bern3D model. We found that while during the Early Holocene the AMOC recovered from its weak deglacial state, it experienced a weakening between 9.2 to 8 ka BP, coinciding with North Atlantic meltwater pulses. From 6.5 ka BP onward, the AMOC strength stabilized, reaching its pre-industrial state around ~18 Sv. Hence, according to future projections, anthropogenic climate change may result in an AMOC slowdown unprecedented for most of the ongoing Holocene interglacial.
地球系统模型和古重建表明,大西洋经向翻转环流(AMOC)强度的变化对全球气候有着深远影响。虽然末次冰消期经历了AMOC的大幅变化,但全新世期间AMOC变化的证据却很有限。在此,我们通过量化北大西洋深部平均底层水平流强度,给出了全新世AMOC的重建结果。为此,我们使用Bern3D模型,从具有千年分辨率的沉积Pa/Th记录中估算体积流量。我们发现,全新世早期AMOC从较弱的冰消期状态恢复,但在公元前9200年至8000年期间经历了一次减弱,这与北大西洋融水脉冲同时发生。从公元前6500年起,AMOC强度稳定下来,在约18 Sv左右达到工业化前状态。因此,根据未来预测,人为气候变化可能导致AMOC放缓,这在全新世大部分持续的间冰期都是前所未有的。