Gravity and inertia-gravity internal waves: Breaking processes and induced mixing

Internal gravity waves, whether influenced or not by the Earth's rotation, arc ubiquitous dynamical features in the stratosphere and in the interior of the ocean. We review the mechanisms by which such waves may break when propagating in an infinite (possibly moving) fluid with uniform stratification. The methods and models used to quantify mixing in a stably-stratified fluid are next recalled. The mixing properties induced by the breaking waves as obtained from several field, experimental and numerical experiments reported in the literature are presented.