The AMOC Question: What the New Evidence Actually Changes
For years, the possibility of a collapse of the Atlantic ocean circulation system occupied a familiar mental category: serious, but distant. It was the kind of climate risk that resurfaced periodically and could still be filed away as too uncertain, too remote or too dependent on disputed models to influence present decisions. That framing is becoming harder to maintain. Scientists have not suddenly agreed that collapse is imminent, and no new study has produced a reliable countdown. The more important change is that severe weakening now appears more plausible than the average of earlier model projections suggested, while newer work also indicates that AMOC stability may depend on the rate and pathway of forcing rather than on a single fixed warming threshold. A 2026 study used present-day observations to constrain climate-model projections of the Atlantic Meridional Overturning Circulation, or AMOC. Its strongest-performing method estimated that the circulation could weaken by abo...