Contributions by speaker > Richet Oceane

In many regions of the ocean, the abyssal flow is dominated by tidal flow. A large fraction
of the tidal energy input in the ocean is dissipated via the generation of internal waves above
rough topography. Idealised simulations suggest that internal tide energy is transferred and
dissipated at smallerscales by the formation of a resonant triad between near-inertial waves,
internal tides and subharmonics waves. Furthermore, the energy dissipation is enhanced at the
critical latitude (28.8°), corresponding to the Parametric Subharmonic Instability (PSI).
In the ocean, the presence of background flow, for instance due to the passage of a mesoscale
eddy, can modify energy transfer mechanisms and the amount of energy dissipation. In this
study, we investigate the generation and dissipation of internal tides in the presence of a back-
ground flow. We use a high-resolution two-dimensional nonhydrostatic numerical model (the
MITgcm), with realistic multiscale topography representing the Brazil basin region. The pur-
pose of this study is to understand the impact of the mean flow on the generation and dissipation
of tidal waves. Our particular interest is how the maximum of energy dissipation at the critical
latitude is impacted by the mean flow.