Note on the redistribution and dissipation of tidal energy over mid-ocean ridges

Xinfeng Liang; Carl Wunsch

doi:10.3402/tellusa.v67.27385

Note on the redistribution and dissipation of tidal energy over mid-ocean ridges

Tellus

Volume 67 (2015): Issue 1

By: Xinfeng Liang and Carl Wunsch

Open Access

|Dec 2015

Abstract

The redistribution and dissipation of internal wave energy arising from the conversion at mid-ocean ridges of the barotropic tide is studied in a set of numerical experiments. A two-dimensional non-hydrostatic model with 100m horizontal and 10–25m vertical resolution is used to represent the detailed processes near an idealised ridge. Conventional internal wave beams at the tidal frequency, ω_M₂, appear. At the ridge crest, strong tidal energy dissipation occurs that both mixes the fluid and generates strong near-inertial oscillations radiating in near-horizontal beams. Resonant triad interaction between the tidal and inertial motions in turn produces beams at (ω_M₂ − f), and with high shear, thus effectively mixing fluid at considerable heights above the ridge crest.

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