Transient Stratospheric Planetary Waves Generated by Tropospheric Forcing

Abstract

In this paper the tropospheric-stratospheric system is modeled as a two-layer, quasigeostrophic atmosphere, and the modal and nonmodal solutions that arise from an impulse forcing within the troposphere are found. Regardless of the nature of the zonal flow, the troposphere can support disturbances over a broad range of wavenumbers, whereas the stratosphere solutions have significant amplitudes only at low wavenumbers. The results are applied to observational data given by a tropospheric-stratospheric analysis. It is shown that explosive baroclinic disturbances within the troposphere can generate transient waves within the stratosphere.