Internal Gravity Waves

The ocean's interior is filled with waves that can only exist because the ocean is vertically stratified in temperature and salinity. Like waves at the ocean surface, internal waves are restored by gravity. These internal gravity waves are generated by wind, tides, and low-frequency flows. As internal waves propagate through the ocean, they interact with low-frequency background flows, topography, and other waves, facilitating an energy cascade to smaller scales, and eventually turbulence. The turbulent mixing is relevant for the general ocean circulation, impacting climate and the dispersion of tracers, like nutrients. In recent decades, the quality of observations and numerical simulations of internal wave processes, and their interpretation, has improved significantly, leading to rapid advances in internal wave research.