Barotropic and baroclinic tides on the Sydney continental shelf

Analyses of temperature and current meter data collected from a shore-normal mooring array have been used to identify the shoreward propagating component of the semidiurnal internal tide on the Sydney shelf. The amplitude of the internal tide at the coast was found to be surprisingly large by comparison with the barotropic tide and not significantly attenuated as the tide progresses shoreward. The large amplitude of the internal tide at the coast is shown to be a result of the significant level of reflection which occurs at the coast. This result is significant since cases where shoreward propagating internal tides reflect off coastal boundaries are rare. A linear model is able to describe the structure of individual packets of internal tides across the shelf which have durations of 3–4 days.