A new study shows that a ban on ozone-depleting chemicals has led to a slow recovery of the Earth's protective ozone layer. Researchers say within the next 100 years, the ozone layer could be as strong as it was 25 years ago. But there's still a lot of uncertainty about the recovery process.
More ozone FACTS:
http://www.epa.gov/ozone/science/sc_fact.html
http://www.ozonelayer.noaa.gov/science/basics.htm