Propagation 3D d'ondes inertielles au sein d'un champ turbulent mésoéchelle

A current problem in physical oceanography is to identify the sources of energy at the origin of the abyssal mixing associated with thermohaline circulation. An important source is the inertial waves generated by wind. However, the mechanisms driving this energy from the surface to the deep mixing remain poorly understood. We study here the tridimensional propagation of inertial waves in a fully turbulent mesoscale eddy field with a primitive equations numerical model. After presenting a review of works to date, we describe various methods for extracting the inertial signal. The 3D propagation of inertial waves is then described and rationalized. In particular, two dramatic maxima of the vertical velocity have been found around 100 m and 1700 m. The deep maximum is explained by the decoupling - induced by mesocale eddies - between high and low vertical modes of inertial velocities. Finally, a new resonance mechanism, associated with the deep maximum, generating small horizontal scales and a frequency twice the inertial frequency, is described. These characteristics suggest that the strong deep vertical velocities could participate to abyssal mixing.