Beta drift of an inertial oscillation
= Beta drift of an inertial oscillation
On a <beta plane>, the turning rate of an <inertial oscillation> is larger on the poleward side of its orbit than on the equatorward side. For initial speed $V$ and $\beta V/f_0^2\ll1$, this asymmetry produces westward mean drift of magnitude $\beta V^2/(2f_0^2)$.