Ocean Tide and Waves Beneath the Ross Ice Shelf, Antarctica

Abstract

The ocean tide in the southern Ross Sea is principally diurnal. The tropic tide range (double amplitude) is between 1 and 2 meters, depending on the location, and is closely related to the local water-layer thickness. The range of the tropic tide is more than three times the range of the equatorial tide. Cotidal and coamplitude charts were made for the largest diurnal constituents, K 1 and O 1 and a provisional cotidal map was made for the semidiurnal constituent M 2 . The amplitudes of the diurnal tide constituents are larger in the Ross Sea than in the adjacent southern Pacific Ocean, indicating the existence of a diurnal resonance related to the shape and depth of the sea. Waves related to ocean swell propagate into the ice-covered region from the northern Ross Sea. These waves have amplitudes near 1 centimeter, and periods in the range 1 to 15 minutes. The speed at which these waves travel is successfully predicted by flexural wave theory.

Flow of the Ross Ice Shelf, Antarctica, is modulated by the ocean tide

“…Each station recorded a strong diurnal signal, consistent with a linear response to ocean tidal fields of the Ross Sea region (Williams and Robinson, 1979). In addition to this diurnal-scale variability, each station possesses a ∼14 day amplitude variation that is likely to be due to the familiar spring-to-neap cycle associated with superposition of solar and lunar tidal forcing, but may also contain both long-period tidal effects (e.g.…”

Current patterns in McMurdo Sound, Antarctica and their relationship to local biotic communities

“…Sound have indicated diurnal periodicity in current speed and/or direction (Gilmour et al 1960(Gilmour et al , 1962Tressler and Ommundsen 1962;Littlepage 1965;Heath 1977;Raytheon Service Company 1983;Lewis and Perkin 1985) which are closely associated with tidal height observations from McMurdo Sound (Heath 1977;Raytheon Service Company 1983) or from the Ross Ice Shelf (Thiel et al 1960;Williams and Robinson 1979). Tidal currents are controlled directly by equilibrium tidal motion and perhaps by tidally-induced flexing of the Ross Ice Shelf (Holdsworth 1977;Doake 1978;MacAyeal 1984), which may accentuate or damp local currents.…”

The temperature and salinity fine structure of the ocean under the Ross Ice Shelf

“…The data set we had to work with is not ideal for applying this reconstruction technique since it would have been desirable to have evenly spaced data over a period at least several days long since the ocean currents are probably largely due to the predominately diurnal tides [ Williams and Robinson, 1979]. The results of the two methods were very similar, but since the McDougall and Ruddick scheme has the advantage of not distorting convective features, such as step structure caused by double-diffusive convection, only the results from that method are reported here.…”

“…The sea surface has a top boundary that is effectively rigid to disturbances with periods less than about one minute but which does move up and down with the tides [Williams and Robinson, 1979]. The sea surface has a top boundary that is effectively rigid to disturbances with periods less than about one minute but which does move up and down with the tides [Williams and Robinson, 1979].…”