pure and applied geophysics

, Volume 133, Issue 4, pp 587–617 | Cite as

Two-layer rotating hydraulics: Strangulation, remote and virtual controls

  • Larry Pratt
  • Larry Armi


The hydraulics of two-layer, rotating channel flow is examined in the limit where the channel width is large compared to the internal Rossby radius of deformation, but small compared to the external deformation radius. In this limit the baroclinic flow is contained in boundary layers along each side wall, while the barotropic flow is distributed over the width of the channel. Width variations along the channel cause the strength of the barotropic flow to vary and the barotropic variations influence the baroclinic boundary layers in two independent ways. The dual nature of this forcing gives rise to a new type of critical condition which we refer to as a ‘remote’ control. ‘Virtual’ and ‘narrows’ controls also arise. Steady solutions can be obtained by solving a pair of simple quadratic equations and examples are given showing various combinations of controls.

Key words

Hydraulics rotating hydraulics remote control virtual control Fram strait strangulation 


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Copyright information

© Birkhäuser Verlag 1990

Authors and Affiliations

  • Larry Pratt
    • 1
  • Larry Armi
    • 2
  1. 1.Physical Oceanography DepartmentWoods Hole Oceanographic InstitutionWoods HoleUSA
  2. 2.Scripps Institution of OceanographyLa JollaUSA

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