Geneva: The Earth’s protective ozone layer is steadily healing, with the 2024 Antarctic ozone hole reported smaller than in recent years, the World Meteorological Organization (WMO) said in its latest bulletin. The positive trend reflects decades of global cooperation and successful implementation of the Montreal Protocol.
The WMO Ozone Bulletin, released ahead of World Ozone Day (16 September) and the 40th anniversary of the Vienna Convention, highlights the role of science-driven international action in reversing ozone depletion.
“Forty years ago, nations came together, guided by science, to protect the ozone layer,” said UN Secretary-General António Guterres. “Today, the ozone layer is healing—a powerful reminder that global cooperation can solve planetary crises.”
Growing evidence shows the ozone layer is on track for recovery as ozone-depleting substances decline, highlighting global progress in protecting the planet.@WMO’s Ozone & UV Bulletin has the latest updates: https://t.co/AbUp8xSF5npic.twitter.com/g0YO3n1TsR
— UN Environment Programme (@UNEP) September 18, 2024
Under the Montreal Protocol, over 99% of ozone-depleting substances—used in refrigeration, air conditioning, firefighting foam, and other products—have been phased out. The ozone layer is now projected to return to 1980s levels by mid-century, reducing risks of skin cancer, cataracts, and ecosystem damage.
WMO Secretary-General Celeste Saulo emphasized that the theme for World Ozone Day, “From Science to Global Action,” reflects decades of research and international collaboration that underpin one of the world’s most successful environmental treaties.
Antarctic Ozone Hole Shows Signs of Recovery
The bulletin reported that the 2024 Antarctic ozone hole had a maximum ozone mass deficit of 46.1 million tonnes—below the 1990–2020 average and smaller than the large holes observed between 2020 and 2023. The slow onset of ozone depletion and relatively fast recovery this year signals early signs of long-term recovery.
“Persistent later onset of depletion is a robust indicator of initial recovery,” the WMO noted.
Continuous Monitoring Remains Crucial
Despite the progress, scientists warn that careful monitoring of stratospheric ozone and replacement chemicals remains essential. WMO’s ongoing ozone and UV monitoring networks provide the data necessary for policy guidance and global compliance with the Montreal Protocol.
“Protecting the ozone layer supports human health, ecosystems, and agriculture,” said Matt Tully, Chair of WMO’s Scientific Advisory Group on Ozone and Solar UV Radiation. “It also advances multiple UN Sustainable Development Goals, including good health, climate action, zero hunger, and life on land.”
According to the bulletin, total stratospheric ozone levels in 2024 were higher across much of the globe, reflecting both natural fluctuations and the long-term success of international interventions.
The WMO’s report underscores that science, collaboration, and sustained action remain the cornerstones of protecting the ozone layer—and by extension, life on Earth.
