Publications

Export 2 results:
Sort by: Author Title Type [ Year  (Desc)]
2016
Musgrave, RC, Pinkel R, MacKinnon JA, Mazloff MR, Young WR.  2016.  Stratified tidal flow over a tall ridge above and below the turning latitude. Journal of Fluid Mechanics. 793:933-957.: Cambridge University Press   10.1017/jfm.2016.150   Abstract

The interaction of the barotropic tide with a tall, two-dimensional ridge is examined analytically and numerically at latitudes where the tide is subinertial, and contrasted to when the tide is superinertial. When the tide is subinertial, the energy density associated with the response grows with latitude as both the oscillatory along-ridge flow and near-ridge isopycnal displacement become large. Where $f\neq 0$ , nonlinear processes lead to the formation of along-ridge jets, which become faster at high latitudes. Dissipation and mixing is larger, and peaks later in the tidal cycle when the tide is subinertial compared with when the tide is superinertial. Mixing occurs mainly on the flanks of the topography in both cases, though a superinertial tide may additionally generate mixing above topography arising from convective breaking of radiating waves.

Musgrave, RC, MacKinnon JA, Pinkel R, Waterhouse AF, Nash J.  2016.  Tidally driven processes leading to near-field turbulence in a channel at the crest of the Mendocino Escarpment*. Journal of Physical Oceanography. 46:1137-1155.   10.1175/jpo-d-15-0021.1   AbstractWebsite

In situ observations of tidally driven turbulence were obtained in a small channel that transects the crest of the Mendocino Ridge, a site of mixed (diurnal and semidiurnal) tides. Diurnal tides are subinertial at this latitude, and once per day a trapped tide leads to large flows through the channel giving rise to tidal excursion lengths comparable to the width of the ridge crest. During these times, energetic turbulence is observed in the channel, with overturns spanning almost half of the full water depth. A high-resolution, nonhydrostatic, 2.5-dimensional simulation is used to interpret the observations in terms of the advection of a breaking tidal lee wave that extends from the ridge crest to the surface and the subsequent development of a hydraulic jump on the flanks of the ridge. Modeled dissipation rates show that turbulence is strongest on the flanks of the ridge and that local dissipation accounts for 28% of the energy converted from the barotropic tide into baroclinic motion.