ESS227
Prof. Jin-Yi Yu
Rossby
Wave
•The wave type that is of most importance for large-scale meteorological processes is the Rossby wave, or planetary wave.
•In an inviscid barotropic fluid of constant depth (where the divergence of the horizontal velocity must vanish), the Rossby wave is an absolute vorticity-conserving motion that owes its existence to the variation of the Coriolis parameter with latitude, the so-called β-effect.
•More generally, in a baroclinic atmosphere,
the Rossby wave is a potential vorticity-conserving motion that
owes its existence to the isentropic gradient of potential vorticity.
