= Rossby-gravity waves
{c}
{wiki}
= Rossby-gravity wave
{c}
{synonym}
= Yanai wave
{c}
{synonym}
= Mixed Rossby-gravity wave
{synonym}
The <Yanai wave> is the $n=0$ branch of the <equatorial shallow-water dispersion relation> with <positive frequency>:
$$
k=\frac\omega c-\frac\beta\omega,\qquad v\propto e^{-\beta y^2/(2c)}.
$$
Its <group velocity> is $d\omega/dk=c\omega^2/(\omega^2+\beta c)>0$. At low <frequency> it has westward <phase velocity> but transports <energy> eastward; at high <frequency> its phase and <group velocities> approach $c$.
Back to article page
