The Antarctic ozone layer is after decades of destruction due to anthropogenic emissions. It's a rare win for the environment, and this year, the ozone hole was the smallest it's been since its discovery in 1980.
But a new study shows that it might take longer for the ozone layer to fully recover than originally predicted. Scientists found last year that a new source of chlorofluorocarbons, or CFCs, was seeping into the air. CFCs react with ultraviolet light in the stratosphere and eat away at the ozone layer.