Future Weakening of the Kuroshio Extension Decadal Variability Revealed by an Eddy‐Resolving Global Climate Model

Abstract The Kuroshio Extension (KE) exhibits pronounced decadal variability, influencing marine ecosystems, fisheries, and regional climate. However, how anthropogenic warming affects this variability remains uncertain due to limited satellite records and model resolution constraints. Based on an eddy‐resolving historical‐and‐future transient climate simulation, we find that the KE decadal variability weakens significantly under a high‐emissions scenario. This weakening likely results from a disruption of the coupled ocean‐atmosphere delayed oscillation, which involves basin‐scale atmospheric circulation both forcing and responding to KE variations. Specifically, warming‐induced strengthening of atmospheric stratification likely suppresses the thermodynamic adjustment, including the deep‐reaching updraft and associated mid‐to‐upper tropospheric responses, typically triggered by oceanic mesoscale warming during the KE stable state. Such suppression disrupts the coupled ocean‐atmosphere delayed oscillation, contributing to the weakened KE decadal variability. Our findings imply that the KE system might be less predictable under future warming.