PSI of the Internal Tide on a β Plane: Flux Divergence and Near-Inertial Wave Propagation

• DOI: 10.1175/2011jpo4605.1
• Publication Date: 2011-04-12T13:47:48Z
• Authors: J. Hazewinkel; K. B. Winters
• Keywords: Inertial wave; Internal tide; Energy flux; Mooring; Kelvin wave; Turbulence Modeling

Abstract The dynamics of a forced, low-mode oceanic internal tide propagating poleward on β plane are investigated numerically. focus is the transfer energy from to near-inertial oscillations (NIOs) initiated by weakly nonlinear interaction known as parametric subharmonic instability (PSI). It shown that PSI mechanism for generating NIOs in upper ocean, which subsequently radiate depth. exponentially growing eventually reach finite amplitude, and further with leads quasi-steady state dissipation balanced reduction tidal flux. results sensitive prescribed value vertical eddy viscosity νe serves parameterize background turbulence. This sensitivity suggests independent processes leading turbulence ocean able control rate NIOs. For = O(10−5 m2 s−1), flux decreases approximately 15%. much smaller than was found previous numerical studies, but it reasonable agreement recent estimates observations taken near M2/2 inertial latitude Pacific.