( Concentrations of atmospheric ozone -- ...)Atmospheric ozone recovering in mid-latitudes, report shows

Researchers attribute the improvement to both a reduction in ozone-depleting chemicals phased out by the global Montreal Protocol treaty and its amendments and to changes in atmospheric transport dynamics. The study, funded by NASA, is the first to document a difference among stratospheric regions in ozone-level improvement and to establish a cause-and-effect relationship based on direct measurements by multiple satellite andground-based, ozone-monitoring systems.

"We do think we're on the road to recovery of stratospheric ozone, but what we don't know is exactly how that recovery will happen," said Derek Cunnold, a professor of earth and atmospheric sciences at the Georgia Institute of Technology. "Many in the scientific community think it will be at least 50 years before ozone levels return to the pre-1980 levels when ozone began to decline."

The research results will be published Sept. 9, 2006 in the American Geophysical Union's Journal of Geophysical Research-Atmospheres. Georgia Tech research scientist Eun-Su Yang led the study in close collaboration with Cunnold, Ross Salawitch of NASA's JetPropulsion Laboratory at the California Institute of Technology, M. Patrick McCormick and James Russell III of Hampton University, Joseph Zawodny of NASA Langley Research Center, Samuel Oltmans of the NOAA Earth System Research Laboratory and Professor Mike Newchurch at the University of Alabama in Huntsville.

The study's data indicate that atmospheric ozone has stopped decreasing in one region and is actually increasing in the other of the two most important lower regions of thestratosphere.

Scientists attribute the stabilization of ozone levels in the past decade in th
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Source:Georgia Institute of Technology Research News