Abstract: A simple model of the tropospheric circulation, based on a 10-level primitive equation model, is forced by linearly relaxing the potential temperature toward an idealized, zonally symmetric equilibrium field. The model ...

Abstract: wo theories for the nonlinear equilibration of baroclinic waves in a two-layer fluid in a ? channel are tested by comparison with high-resolution numerical simulations. Predictions are tested for a range of parameters (?, ...

Abstract: ortex displacement stratospheric sudden warmings (SSWs) are studied in an idealized model of a quasigeostrophic columnar vortex in an anelastic atmosphere. Motivated by the fact that observed events occur at a fixed ...

Abstract: he fundamental dynamics of ?vortex splitting? stratospheric sudden warmings (SSWs), which are known to be predominantly barotropic in nature, are reexamined using an idealized single-layer f-plane model of the polar vortex. ...

Abstract: A quasigeostrophic, two-layer, ?-plane channel model is used to investigate the dynamics of baroclinic wave packets. A series of experiments are performed in which an unstable flow is maintained by lower-level Ekman friction ...

Abstract: The linear and nonlinear dynamics of layers of anomalously high potential vorticity (PV) are studied in detail. It is well known that PV layers are subject to slow, balanced, mixed barotropic?baroclinic instabilities. In ...

Abstract: The excitation of Rossby waves on the edge of the stratospheric polar vortex, due to time-dependent topographic forcing, is studied analytically and numerically in a simple quasigeostrophic f-plane model. When the atmosphere ...

Abstract: The evolution of the Arctic polar vortex during observed major midwinter stratospheric sudden warmings (SSWs) is investigated for the period 1957?2002, using 40-yr European Centre for Medium-Range Weather Forecasts (ECMWF) ...