Climate models show considerable discrepancies in their future projections around the Atlantic, mainly due to uncertainties in the fate of the Atlantic Meridional Overturning Circulation (#AMOC). #Climate models have previously suggested a reduction in AMOC strength of 32±37% by 2100. But a closer examination, however, gives an estimate of the AMOC slowdown of 51±8%. This refinement mainly results from correcting a bias in South Atlantic surface #salinity, consistent with recent studies emphasizing its role in the proximity to an AMOC tipping point. This more substantial AMOC weakening has key implications for future #adaptation strategies. https://www.science.org/doi/10.1126/sciadv.adx4298