The palette of fronts and cyclones within a baroclinic wave development

Abstract

A study is undertaken of the concurrent development of fronts and cyclones within a growing baroclinic wave. The dynamical framework for the study is that of the semigeostrophic, adiabatic flow of a uniform potential vorticity atmosphere that is sandwiched between two horizontal plates on an f plane. A three-dimensional spectral model is used to examine the growth to finite amplitude of the normal modes of this system for basic states that comprise of a symmetric jetlike baroclinic flow with (and without) a superposition of a uniform barotropic shear of either cyclonic or anticyclonic vorticity. It is demonstrated that the presence of such lateral shear in the ambient environment exerts a profound influence upon the ensuing palette of fronts and cyclones. -from Authors