Antarctic ozone hole - Possible implications for ozone trends in the Southern Hemisphere

• Main Authors: Sze, N. D., Ko, M. K. W., Weisenstein, D. K., Rodriguez, J. M., Stolarski, R. S., Schoeberl, M. R.
• Format: Other/Unknown Material
• Language: unknown
• Published: 1989
• Subjects: 46; Antarctic; Antarc*
• Online Access: http://ntrs.nasa.gov/search.jsp?R=19890066538

Satellite-borne instruments (the Total Ozone Mapping Spectrometer and the Solar Backscattered Ultraviolet Instrument) show that, compared to 1979, total column ozone has a year-round decrease of more than 5 percent in the neighborhood of 60 deg S. The meteorological conditions (warmer temperatures, the absence of polar stratospheric clouds) at these latitudes do not seem to favor heterogeneous chemistry as the direct cause for the observed year-round ozone reduction. A mechanism involving the seasonal transport of ozone-poor air from within the polar vortex to lower latitudes (the so-called 'dilution effect') is proposed as a possible explanation for the observed year-round ozone reduction in subpolar regions. A two-dimensional model with an imposed springtime Antarctic ozone depletion is used to study the post-ozone hole impact on the spatial and temporal distributions of column ozone at latitudes north of 60 deg S. It is found that the time constant associated with the dilution effect in the latitude region 40-60 deg S is about 1 year, long enough to contribute to the observed year-round decrease of total ozone in that region.