A new math-based computer model developed by the group to predict the timing of ozone hole recovery indicates that the ozone hole over the Antarctic will recover around 2068, 18 years later than previously believed.
And while later revisions to the Montreal Protocol completely eliminated legal production of most of ozone-depleting chemicals, the researchers also found that the ozone hole has not yet started to significantly shrink, something they predict will not start to occur until 2018.
"The Antarctic ozone hole is the poster child of ozone loss in our atmosphere," says lead author Paul Newman, a research scientist at NASA's Goddard Space Flight Center, Greenbelt, Md. "Over areas that are farther from the poles like Africa or the continental U.S., the annually averaged levels of upper atmospheric ozone are only three to six percent below natural levels. But, over Antarctica, ozone is 70 percent lower in the spring. This new method allows us to more accurately estimate ozone-depleting gases over Antarctica, and how they will decrease over time, reducing the ozone hole area."
Newman's team also further indicated that greenhouse gas-forced climate change will have only a small impact on the Antarctic stratosphere and recovery of the ozone hole.
The upper ozone layer is important because it blocks 90-99 percent of the sun's ultraviolet radiation from making contact with Earth. This solar radiation can cause skin cancer, genetic damage, eye damage and can impact marine life.
