Abstract: A potent mechanism for the generation of low-frequency atmospheric variability on vortex basic states consisting of a single potential vorticity jump, or contour, separating two regions of uniform equivalent barotropic ...

Abstract: The barotropic instability of a forced, axisymmetric vortex patch is examined and linked to prior work on the destabilization of a single Rossby wave via triad interactions. Both oscillatory instabilities, which share ...

Abstract: Analysis of frequency distribution functions of potential vorticity (PV) on middleworld isentropic surfaces that intersect the tropopause reveals that dynamics on these surfaces are dominated by the tropopause separating ...

Abstract: The general character of stationary Rossby waves in a state with homogenized tropospheric PY as opposed to more conventionally assumed PV distributions is discussed. It is shown that the expected changes in wave pattern ...

Abstract: The ability of four-dimensional variational (4DVAR) assimilation of data to reduce various observational error structures in a quasigeostrophic model is studied. It is found that 4DVAR with assimilation periods on the order ...