World Meteorological Organisation (WMO) has revealed that the Earth’s protective ozone layer is healing and that the ozone hole in 2024 was smaller than in recent years, according to its latest report, which contains welcome scientific news for people and planetary health.
 
The WMO highlighted yesterday that the low level of ozone depletion observed in 2024 was partly due to naturally occurring atmospheric factors, which drive year-to-year fluctuations. However, it said the long-term positive trend reflected the success of concerted international action.
 
Ozone depletion is triggered by man-made chemicals such as Chlorofluorocarbons (CFCs), which release ozone-destroying chlorine and bromine atoms. The depletion allows more harmful ultraviolet (UV) radiation to reach the surface, increasing risks of skin cancer, eye cataracts, and genetic damage to humans and others.
 
The WMO Ozone report was issued to commemorate World Ozone Day today, and the 40th anniversary of the Vienna Convention, which recognised stratospheric ozone depletion as a global problem and provided the framework for mobilising international cooperation in ozone research, systematic observations, and scientific assessments.

United Nations Secretary-General, António Guterres, said: “Forty years ago, nations came together to take the first step in protecting the ozone layer, guided by science, united in action. The Vienna Convention and its Montreal Protocol became a landmark of multilateral success.  Today, the ozone layer is healing. This achievement reminds us that when nations heed the warnings of science, progress is possible.”
 
According to the Chair of WMO’s Scientific Advisory Group on Ozone and Solar UV Radiation, Matt Tully, despite the great success of the Montreal Protocol in the intervening decades, the work is not yet finished, and there remains an essential need for the world to continue careful systematic monitoring of both stratospheric ozone and ozone-depleting substances and their replacements.