Visualizing the evolution of the stratospheric polar vortex in January 1992

From a GCM simulation of a period in EASOE, the evolution of the northern hemisphere polar vortex is examined by means of a sequence of three dimensional visualizations. Use is made of two key dynamical features, the edge of the polar vortex and the height of the tropopause. This technique clearly shows how the vortex is disturbed by an anticyclonic tropospheric anomaly and how this disturbance vertically propagates up the vortex. An objective method for finding the edge of the vortex is presented.