Transitions between blocked and zonal flows in a rotating annulus with topography

@article{Weeks1997TransitionsBB,
  title={Transitions between blocked and zonal flows in a rotating annulus with topography},
  author={Weeks and Tian and Urbach and Ide and Swinney and Ghil},
  journal={Science},
  year={1997},
  volume={278 5343},
  pages={
          1598-601
        }
}
  • Weeks, Tian, +3 authors Ghil
  • Published 28 November 1997
  • Environmental Science, Physics
  • Science
The mid-latitude atmosphere is dominated by westerly, nearly zonal flow. Occasionally, this flow is deflected poleward by blocking anticyclones that persist for 10 days or longer. Experiments in a rotating annulus used radial pumping to generate a zonal jet under the action of the Coriolis force. In the presence of two symmetric ridges at the bottom of the annulus, the resulting flows were nearly zonal at high forcing or blocked at low forcing. Intermittent switching between blocked and zonal… 
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References

SHOWING 1-10 OF 59 REFERENCES
Propagation of barotropic vortices over topography in a rotating tank
A small-scale cyclonic vortex in a relatively broad valley tends to climb up and out of the valley in a cyclonic spiral about the centre, and when over a relatively broad hill it tends to climb
A Simple Mechanism for Blocking
Abstract Numerical experiments show that blocking in a barotropic atmosphere can occur as a resonant enhancement of Rossby lee waves forced by two stationary sources of potential vorticity. In
Persistent Anomalies, Blocking and Variations in Atmospheric Predictability
Abstract We consider regimes of low-frequency variability in large-scale atmospheric dynamics. The model used for the study of these regimes is the fully-nonlinear, equivalent-barotropic vorticity
THE DYNAMICS OF LONG WAVES IN A BAROCLINIC WESTERLY CURRENT
Abstract Previous studies of the long-wave perturbations of the free atmosphere have been based on mathematical models which either fail to take properly into account the continuous vertical shear in
Multiple Flow Equilibria in the Atmosphere and Blocking
Abstract A barotropic channel model is used to study the planetary-scale motions of an atmosphere whose zonal flow is externally driven. Perturbations are induced by topography and by d barotropic
Laboratory model of a planetary eastward jet
The concentration of eastward planetary currents into strong wavy jets is a major feature of the atmospheric general circulation (for example, the jet stream) and of oceanic currents (for example,
Shear flow instabilities and Rossby waves in barotropic flow in a rotating annulus
The primary instability of an azimuthal jet is studied experimentally in a rotating annulus with a rigid upper lid (infinite Rossby deformation radius) and a sloping bottom (topographical beta
Dynamics of Weather Regimes: Quasi-Stationary Waves and Blocking.
Abstract We hypothesize that periods of quasi-stationary behavior in the large scales are integrally associated with an organized behavior of the synoptic scales, thus the terminology “weather
Resonant Topographic Waves in Barotropic and Baroclinic Flows
Abstract The problem of resonant, topographic quasi-geostrophic waves is examined analytically by exploiting simplifications that arise when the flow is nearly resonant. The barotropic and
...
1
2
3
4
5
...