Thursday, 7 November 2002: 10:50 AM
A climatology of vortex life cycles in the stratosphere and their effect on tracer transport
The size, duration, and movement of stratospheric polar vortices and closed anticyclonic circulations have a first order impact on the ozone budget and on the distribution of stratospheric trace gases. U. K. Met. Office global analyses are used to test new methodologies which identify the position and structure of both polar vortices and anticyclones in the stratosphere. Once identified, these coherent circulations are treated as airmass "objects". Polar vortex life cycles will be shown in both hemispheres from the tropopause to the stratopause in the form of 3 dimensional animations of the stratosphere. This visualization technique offers a clear physical picture of polar vortex formation and decay, planetary wave breaking along the edges of the Arctic vortex as well as the Antarctic vortex in spring. Life cycles of the Aleutian High in the Northern Hemisphere and of the "Australian High" in the Southern Hemisphere are readily apparent as are stratospheric warming events. A case study will then be presented where trajectory mapping techniques show the evolution of SAGE II, HALOE, and POAM chemical data over the course of a representative Aleutian High and Australian High life cycle.
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