Amplification of the Divergent Component From Balanced Motions and Forward Kinetic Energy Cascade in an Ocean‐Atmosphere Simulation

Abstract An accurate depiction of kinetic energy (KE) exchanges across oceanic scales, known as KE cascades, is essential for enhancing the predictive capabilities of climate models. Several studies have highlighted that submesoscale flows and internal gravity waves can significantly affect KE cascades in the ocean. In this study, we investigate the response of KE cascades in a coupled ocean‐atmosphere simulation (COAS). By comparing this simulation with another that has an identical oceanic configuration but with a different atmospheric forcing resolution, we observed a larger production of small‐scale motions, such as submesoscale structures and internal gravity waves, in the COAS. This increase in small‐scale structures amplifies the forward KE cascade. By applying a dynamical filter to partition ocean motions into balanced and non‐balanced motions, it is revealed that the high frequency of the divergent component of submesoscale balanced motions is the main driver of the more vigorous forward KE cascade in a coupled ocean‐atmosphere system.