Parameterization of Near‐Inertial Waves Induced Mixing Under the Influence of Mesoscale Eddies

Near‐inertial waves (NIWs) are an important source of ocean mixing and their proper parameterization in eddy‐permitting ocean models is crucial for a variety of processes. Existing parameterization schemes have not considered the influence of background mesoscale eddies. By using mooring data, shipborne turbulence microstructure measurements, reanalysis data, and a slab model, we develop a new NIW‐induced mixing parameterization scheme that takes into account the influence of background mesoscale eddies. The development process consists of four steps: (a) determining the upper mixed layer depth using a critical Richardson number criterion; (b) quantifying wind power input into NIWs; (c) calculating near‐inertial energy flux through the bottom of the upper mixed layer; (d) determining the vertical dissipation structure in the ocean interior. Shipborne turbulent microstructure profiles are utilized to validate the proposed new scheme. It is found that, by applying this new parameterization scheme, the root‐mean‐squared error of , where is the parameterized diffusivity, is reduced by 28%–37% and 27%–53% under negative and positive background vorticity, respectively. This shows a significant improvement of the present new scheme over the existing scheme, which applies to both negative and positive background vorticities.