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Abstract By synthesizing recent studies employing a wide range of approaches (modern observations, paleo reconstructions, and climate model simulations), this paper provides a comprehensive review of the linkage between multidecadal Atlantic Meridional Overturning Circulation (AMOC) variability and Atlantic Multidecadal Variability (AMV) and associated climate impacts. There is strong observational and modeling evidence that multidecadal AMOC variability is a crucial driver of the observed AMV and associated climate impacts and an important source of enhanced decadal predictability and prediction skill. The AMOC‐AMV linkage is consistent with observed key elements of AMV. Furthermore, this synthesis also points to a leading role of the AMOC in a range of AMV‐related climate phenomena having enormous societal and economic implications, for example, Intertropical Convergence Zone shifts; Sahel and Indian monsoons; Atlantic hurricanes; El Niño–Southern Oscillation; Pacific Decadal Variability; North Atlantic Oscillation; climate over Europe, North America, and Asia; Arctic sea ice and surface air temperature; and hemispheric‐scale surface temperature. Paleoclimate evidence indicates that a similar linkage between multidecadal AMOC variability and AMV and many associated climate impacts may also have existed in the preindustrial era, that AMV has enhanced multidecadal power significantly above a red noise background, and that AMV is not primarily driven by external forcing. The role of the AMOC in AMV and associated climate impacts has been underestimated in most state‐of‐the‐art climate models, posing significant challenges but also great opportunities for substantial future improvements in understanding and predicting AMV and associated climate impacts.
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This content will become publicly available on May 2, 2026
Stratospheric control of the linkage between the AMOC and Atlantic multidecadal variability
Abstract The ocean’s role in Atlantic Multidecadal Variability (AMV) remains intensely debated. The core issue is whether AMV, as an internal climate mode, is driven by variations in Atlantic Meridional Overturning Circulation (AMOC) or by atmospheric processes. Climate models exhibit wide diversity in AMOC-AMV linkages, producing temporal correlations between 0.3-0.8, but no robust explanation for these differences exists. Here, using multi-model intercomparison and perturbation experiments, we propose a dynamical mechanism relating the strength of AMOC-AMV linkage in climate models to stratospheric temperature. This mechanism includes (1) tropospheric midlatitude jet response to stratospheric mean-state temperature anomalies in mid-latitudes and (2) resulting ocean surface density changes that alter the spatial structure of deep-water formation in the subpolar North Atlantic and hence AMOC-AMV connection. Specifically, colder stratospheric temperatures produce tighter linkage through the northward jet shifts and a stronger AMOC, with enhanced deep-water formation in the Labrador and Irminger Seas relative to the Nordic Seas. Models with a warm stratospheric bias tend to produce weaker linkage. Perturbation experiments imposing stratospheric cooling at mid to high latitudes within two independent climate models support these conclusions. Furthermore, we find that models with stronger AMOC-AMV linkage predict a stronger North Atlantic “warming hole” and weaker 21st-century Arctic amplification. We conclude that these results have significant implications for climate prediction and projections.
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- Award ID(s):
- 2053096
- PAR ID:
- 10609769
- Publisher / Repository:
- AMS
- Date Published:
- Journal Name:
- Journal of Climate
- ISSN:
- 0894-8755
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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