Deduction of Climate Variability From the Total Ozone Record, 1965-2000

 

Author:  Robert D. Hudson
Affiliation: Dept. of Meteorology,
University of Maryland

 

Analysis of the ozone field in the Northern Hemisphere, using both TOMS and Dobson data, has shown that the total ozone field can be separated into three distinct meteorological regimes. These are defined as (1) the tropical regime - between the equator and the upper troposphere subtropical front (2) the midlatitude regime - between the subtropical and polar fronts, (3) the polar regime - between the polar front and the polar vortex. Within each regime, the daily mean total ozone is relatively constant, with a clearly separate value for each regime. The trends in total ozone for the latitude zone between 25 and 60N for the period 1979-92 within each regime are much less than the trend obtained for the whole zone. It has been found that about 50% of the observed zonal trend is due to the movement of the subtropical and polar front northward.

A movement of the sub-tropical and polar fronts implies a change in the weather patterns associated with these fronts, i.e. a climate change. This paper presents an analysis of the movement of the polar and sub-tropical fronts for the period between 1965 and 2002 deduced from both the TOMS and Dobson data sets. The strongest correlation in this movement of the fronts is that with the f10.7 flux. Details of the experimental method and the climate analysis will be presented.