Mesoscale Eddy Kinetic Energy Budgets and Transfers between Vertical Modes in the Agulhas Current

Abstract Western boundary currents are hotspots of mesoscale variability and eddy–topography interactions, which channel energy toward smaller scales eventually down to dissipation. Here, we assess the main eddies sinks in Agulhas Current region from a regional numerical simulation. We derive an eddy kinetic ( ) budget framework vertical modes. It accounts for transfers between reservoirs modes, including channeled by topography. The is dominated (barotropic first baroclinic modes) path intense mean currents. Eddy–topography interactions result major sink, along three different routes, with comparable importance: bottom-intensified time-mean currents, generation higher bottom friction. modes takes forms Northern Current, where it corresponds nonlinear on slope, Southern (linear) internal gravity waves over Away shelf, gain inverse turbulent cascade. However, remains net source due strong eddies, modulated topography, especially Current. shows that local dominates budget, contrary paradigm decay upon western boundaries.