Zonal flow generation:
the local turbulence view.
¥CHM becomes 2D Euler equation in the limit β0, kρ°. Hence expect similarities to 2D turbulence.
¥Inverse energy cascade and direct cascade of potential enstrophy (Fj¯rtoftÕ53 argument).
¥Inverse cascade leads to energy condensation at large scales.
¥These are round(ish) vortices in Euler.