Internal tides and energy fluxes over Great Meteor Seamount

T. Gerkema (1) , H. van Haren (1)

1 NIOZ - Royal Netherlands Institute for Sea Research

Internal-tide energy fluxes are determined halfway over the southern slope of Great Meteor Seamount (Canary Basin), using data from combined CTD/LADCP yoyoing, covering the whole water column. The strongest signal is semi-diurnal and is concentrated in the upper few hundred meters of the water column. An indeterminacy in energy flux profiles is discussed; it is argued that a commonly applied condition used to uniquely determine these profiles does in fact not apply over sloping bottoms. However, the vertically integrated flux can be established unambiguously. The observed results are compared to the outcome of a numerical internal-tide generation model. For the semi-diurnal internal tide, the vertically integrated flux found in the model corresponds well to the observed one. For the diurnal tide, however, the former is much smaller; this points to non-tidal origins of the diurnal signal, which is indeed to be expected at this latitude (30°), where near-inertial and diurnal periods coincide.

Domaines: Océan, Atmosphère

T. Gerkema, H. van Haren. Internal tides and energy fluxes over Great Meteor Seamount. Ocean Science Discussions, 2007, 4 (2), pp.371-398. ⟨hal-00298473⟩