Interaction between a slowly moving planetary—scale dipole envelope rossby soliton and a wavenumber— two topography in a forced higher order nonlinear Schrödinger equation

摘要: A parametrically excited higher—order nonlinear Schrodinger (NLS) equation is derived to describe the interaction of a .slowly moving planetary—scale envelope Rossby soliton for zonal wavenumber-two with wavenumber—two topography under LG—type dipole near-resonant conditioa The numerical solution this made. It found that in weak background westerly wind satisfying near—resonance condition, when an incipient located topographic trough and propagates slowly, it can be amplified through near—resonant forcing exhibit oscillatioa However, break up after long time excite train small amplitude waves propagate westward. In addition, observed soliton—topography topographically near—resonantly forced has slowly westward propagation, but eastward propagation certain time. instantaneous total streamfunction fields are bear remarkable resemblance initiation, maintenance decay omega—type blocking high blocking. perturbation theory used examine role shown amplifying process soliton, due inclusion higher order terms its group velocity gradually tends equal phase so block carrier wave phase—locked at This shows initiation transfer system from dispersion nondispersion. there exists reverse during appears latitude regions, could regarded as possible mechanism establishment