Tropopause Folds and Synoptic-Scale Baroclinic Wave Life Cycles

Abstract

The linear stability of three midlatitude zonal mean states of varying baroclinicity and barotropy is examined using a primitive equation stability analysis under the anelastic approximation. Each of these basic states includes both tropospheric and stratospheric regions with realistic properties compared with those of the earth´s atmosphere in midlatitudes. In all three cases, the fastest growint synoptic-scale modes delivered by the linear stability analysis have wavelengths of approximately 4000 km. The nonlinear evolution of these synoptic-scale modes is explored using a three-dimensional anelastic finite-difference model whose zonal scale is chosen to be equal to the wavelength of the fastest growing mode of linear theory...