Abstract: Three-dimensional views of midlatitude stratospheric intrusions are presented. The views are obtained by plotting a surface of constant potential vorticity (PV), where the PV is diagnosed from a 6-day run of the U.K. ...

Abstract: The degree to which the Southern Hemisphere polar vortex is isolated against horizontal (isentropic) mixing is investigated using data from the Halogen Occulation Experiment (HALOE), U.K. Meteorological Office (UKMO) ...