Scientists say the hole in the ozone layer over Antarctica is likely to start getting smaller - 25 years after it was discovered.
The hole, which appears each year, was first reported by British scientist Jonathan Shanklin and two others in May 1985.
It has been about the same size for the past 15 years.
Jonathan Shanklin says he expects ozone depletion to begin reducing each year, with ozone levels eventually returning to natural levels in 2080.
National Institute of Water and Atmospheric Research scientist Richard Mackenzie says the recovery may have started already.
He says the likely recovery pattern is uncertain because of complex interactions between ozone depletion and climate change factors.