The ozone layer that shields life from cancer-causing solar rays is showing its first sign of recovery after years of dangerous depletion, a U.N. study said on Wednesday, in a rare piece of good news on the environment.
Experts said it was largely down to global action - a 1987 ban on man-made gases that damage the fragile high-altitude screen. The agreement would help prevent millions of cases of skin cancer and other conditions, they added.
The ozone hole that appears over Antarctica has also stopped growing bigger every year, though it will be about a decade before it starts shrinking, said the report co-produced by the World Meteorological Organization and the U.N. Environment Programme.
"International action on the ozone layer is a major environmental success story ... This should encourage us to display the same level of urgency and unity to tackle the even greater challenge of tackling climate change," said WMO Secretary-General Michel Jarraud.
Past studies have suggested the ozone layer has stopped getting worse.
"Now for the first time in this report we say that we see indications of a small increase in total ozone. That means recovery of the ozone layer in terms of total ozone has just started," said WMO senior scientific officer Geir Braathen.
The 1987 Montreal Protocol that banned or phased out ozone depleting chemicals, including chlorofluorocarbons (CFCs) once widely used in refrigerators and spray cans, would prevent 2 million cases of skin cancer annually by 2030 according to UNEP.
The agreement would also help avert damage to wildlife, agriculture, human eyes and immune systems, the agency added.