HR: 0830h
AN: OS41E-69    [PDF]
TI: Tidal Dynamics and Mixing in the Ross Sea
AU: * Robertson, R
EM: rrobertson@awi-bremerhaven.de
AF: Alfred-Wegener-Institut, Busse Str. 24, Bremerhaven, 27570 Germany
AU: Beckmann, A
EM: beckmann@awi-bremerhaven.de
AF: Alfred-Wegener-Institut, Busse Str. 24, Bremerhaven, 27570 Germany
AU: Hellmer, H
EM: hhelmer@awi-bremerhaven.de
AF: Alfred-Wegener-Institut, Busse Str. 24, Bremerhaven, 27570 Germany
AB: In certain areas of the Southern Ocean, tidal energy is believed to foster the mixing of different water masses, which contribute to the formation of deep and bottom waters. Since the Ross Sea is one of the major ventilation sites of the global ocean abyss, we investigated tidal dynamics and mixing there using a three-dimensional sigma coordinate model, the Regional Ocean Model Systems (ROMS). Internal tides were generated at the continental shelf/slope break and other areas of steep topography. Additionally, strong vertical shears in the horizontal velocities, indicative of mixing, occurred at the back and edges of the Ross Ice Shelf and along the continental shelf/slope break. Estimates of lead formation due to divergence of baroclinic velocities were much higher than those of barotropic velocities, reaching over 10\% at the continental shelf/slope break. For these simulations, realistic topography and hydrography were used from existing observational data together with four tidal constituents: two semi-diurnal, M2 and S2, and two diurnal, K1 and O1. The model fields showed reasonable agreement with 10 tidal elevation observations and over 35 tidal current measurements.
DE: 4207 Arctic and Antarctic oceanography
DE: 4544 Internal and inertial waves
DE: 4560 Surface waves and tides (1255)
DE: 4568 Turbulence, diffusion, and mixing processes
SC: OS
MN: 2002 Ocean Sciences Meeting