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General Characteristics of Density-Turbidity Currents in the Ross Sea (Antarctica)

  • S. Gremes Cordero
  • E. Salusti
Conference paper

Abstract

To investigate thermodynamic currents in Antarctica, we here discuss quasi-steady density currents flowing over a regular slope and their hydrodynamic stability, considering also bottom erosion phenomena: in other words, the current is assumed to exchange sediments with the bottom. To simplify this complex problem a model of sediment evolution is assumed. As in recent work the excess mass due to the bottom erosion and deposition is assumed to depend only on the current stress on the bottom. A nonlinear equation considering both the time and space variability of these “density-turbidity” currents for a two-layer model is obtained and a novel criterion to identify the “ignition” point of these density-turbidity currents is discussed. In Polar Oceans these interactions can play a fundamental role in the generation of new water masses, as a result of violent hydrodynamic instability concerning the downslope motion of dense shelf water along submarine canyons.

Keywords

Dense Water Shelf Break Gravity Current Turbidity Current Hydrodynamic Instability 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Italia, Milano 1999

Authors and Affiliations

  • S. Gremes Cordero
    • 1
  • E. Salusti
    • 2
  1. 1.Dipartimento di FisicaUniversità “La Sapienza”RomeItaly
  2. 2.INFN, Dipartimento di FisicaUniversità “La Sapienza”RomeItaly

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