Work

Reversible Atlantic overturning despite continued Greenland ice sheet melt

Year: 2026

Type: article

Abstract: The Atlantic Meridional Overturning Circulation (AMOC) is considered vulnerable to irreversible weakening or collapse under global warming and related Greenland ice sheet (GrIS) melt, yet its resilience to either forcing remains poorly constrained. Here, we use a carbon dioxide emission-driven Earth system model with an interactive GrIS to assess AMOC reversibility under a range of idealized carbon dioxide emission pathways that produce near-linear global warming up to 10 kelvins (K), stabilization across 1.5 to 9 K, and subsequent cooling. We find that although the AMOC reaches threshold-defined collapsed states, these do not represent dynamical tipping in this model: The overturning weakens quasi-linearly with global mean temperature increase yet consistently and promptly recovers under cooling. In contrast, GrIS mass loss accelerates with warming, continues through stabilizations, and is only slowed by cooling, committing the planet to long-term sea level rise. These results reveal contrasting resilience across climate system components: Under transient carbon dioxide forcing, AMOC strength remains dynamically reversible despite continued Greenland meltwater input, whereas the GrIS is locked into persistent decline. Our findings underscore the urgency of rapid emission cuts to limit climate overshoot, AMOC weakening, and irreversible ice sheet loss.

Source: Science Advances

DOI: 10.1126/sciadv.aee5373