AMOC Weakening Shapes Ocean Heat Storage Patterns Under Strong Idealized Warming

Abstract The ocean absorbs most of the excess heat induced by anthropogenic greenhouse gas emissions. Among the different processes, a key role has been attributed to the Atlantic Meridional Overturning Circulation (AMOC), both for heat uptake and redistribution among basins, yet a comprehensive view remains elusive. In this study, we investigate how a weakening of the AMOC would influence ocean heat storage in a warming climate by comparing two idealized experiments with two different AMOC evolutions from the global climate model EC‐Earth3, after abrupt carbon dioxide quadrupling. We find that AMOC weakening influences both vertical and inter‐basin heat redistribution. For a stronger AMOC decline, more heat is stored in the Indo‐Pacific Ocean and in the intermediate ocean layers above 700 m, while less heat accumulates in the deeper ocean layers, especially in the Atlantic. Globally, we find a 3% increase in cumulated ocean heat uptake at the end of the simulations.