The World Meteorological Organisation (WMO) says the Earth’s protective ozone layer is healing, with the 2024 Antarctic ozone hole smaller than in recent years.
This was stated in the WMO new Ozone Bulletin released on World Ozone Day and the 40th anniversary of the Vienna Convention.
The report credits international action under the 1985 Vienna Convention and its Montreal Protocol as responsible for phasing out over 99% of ozone-depleting substances for a long-term rebound.
The ozone layer is projected to return to 1980 levels by mid-century, reducing risks of skin cancer, cataracts, and ecosystem damage from ultraviolet radiation.
WMO Secretary-General Celeste Saulo highlighted the role of decades-long global research and data sharing in the treaty’s success.
The 2024 ozone hole reached a maximum deficit of 46.1 million tonnes on 29 September, smaller and later-forming than the large holes recorded from 2020 to 2023, noting evidence of gradual recovery.
Experts caution that monitoring remains vital to track ozone-depleting substances and their replacements.
The WMO also noted that the Kigali Amendment, aimed at reducing hydrofluorocarbons, is on course to prevent up to 0.5°C of global warming by century’s end.
Protecting the ozone layer supports multiple UN Sustainable Development Goals, including health, climate action, food security, and biodiversity, the WMO said.