"NASA Says Ozone Hole Stabilizing But Won't Fully Recover Until 2070"

"The hole in the ozone layer is stabilizing but will take until about 2070 to fully recover, according to new research by NASA scientists."

"The assessment comes more than two decades after the Montreal Protocol, the international treaty that banned chlorofluorocarbons and other compounds that deplete the ozone layer, which shields the planet from harmful ultraviolet rays.

Levels of chlorine in the atmosphere are falling as a result of the treaty, but have not yet dropped below the threshold necessary to have a shrinking effect on the ozone hole that forms each year over Antarctica, according to scientists at NASA's Goddard Space Flight Center. They presented their findings this week at the annual meeting of the American Geophysical Union in San Francisco."

Tony Barboza reports for the Los Angeles Times December 12, 2013.