Planetary-scale meanders driven by Coriolis force and potential vorticity conservation
4
40
40 m/s
4
Ridge (High P)
Trough (Low P)
Jet axis
Rossby waves propagate westward relative to the mean flow due to the β-effect (meridional PV gradient).
Phase speed: c = U − β/k². When U = β/k², the wave is stationary.
Large amplitudes and slow phase speeds produce blocking patterns — persistent ridges that deflect the jet.