Internal-wave polarization
= Internal-wave polarization
For a propagating, non-cutoff two-dimensional <internal gravity wave> proportional to $e^{i(kx+mz-\omega t)}$, <incompressibility> gives $U=-mW/k$. Thus the oscillatory <velocity field> is perpendicular to the <wavevector> and parallel to the <group velocity>, whereas the <phase velocity> is parallel to the <wavevector>.