Wave-action conservation law
= Wave-action conservation law
{title2=$W_T+\nabla\cdot(\mathbf c_gW)=0$}
In a slowly varying conservative medium, wave action obeys a continuity equation with flux equal to wave-action density times group velocity.
= Wave-action conservation law
{title2=$W_T+\nabla\cdot(\mathbf c_gW)=0$}
In a slowly varying conservative medium, wave action obeys a continuity equation with flux equal to wave-action density times group velocity.