The Earth's protective ozone layer is on track to return to 1980s levels by the middle of this century, with the 2024 Antarctic ozone hole smaller than in recent years, the World Meteorological Organization (WMO) said in a new report. The WMO Ozone Bulletin 2024 said lower ozone depletion this year was partly due to natural atmospheric factors but stressed the long-term improvement reflects the success of global action.

The bulletin was released on World Ozone Day, which also marked the 40th anniversary of the Vienna Convention that laid the foundation for international cooperation on ozone protection. "Forty years ago, nations came together to take the first step in protecting the ozone layer, guided by science, united in action," said UN Secretary-General Antonio Guterres.