The Earth’s ozone layer is showing clear signs of recovery and could fully heal in the coming decades, according to the United Nations. A new report from the UN’s World Meteorological Organization (WMO) revealed that the Antarctic ozone hole was smaller in 2024 compared to recent years—an encouraging sign for global health and the environment.

“Today, the ozone layer is healing,” said UN Secretary-General António Guterres, noting the success as proof that global cooperation guided by science can deliver results.

The WMO’s Ozone Bulletin 2024, released on World Ozone Day and marking 40 years since the Vienna Convention, credited international agreements—especially the 1987 Montreal Protocol—for the progress. That accord led to the elimination of more than 99% of ozone-depleting substances used in refrigeration, air conditioning, and aerosol sprays.

While some year-to-year variations in depletion are due to natural atmospheric conditions, the WMO stressed that the long-term trend clearly shows improvement. The ozone layer is projected to return to 1980s levels by mid-century, sharply reducing risks of skin cancer, cataracts, and ecosystem damage from ultraviolet radiation.

In 2023, the Antarctic ozone hole reached a maximum deficit of 46.1 million tonnes—below the 1990–2020 average. Scientists observed a later-than-usual onset of depletion and a faster recovery afterward, which they identified as evidence of the layer’s gradual restoration.

According to the latest UN scientific assessments, if current policies remain in place, the ozone layer is expected to recover by around 2040 across most of the world, by 2045 over the Arctic, and by 2066 over Antarctica.