The Montreal Protocol, signed in 1987, has been instrumental in this achievement, according to a new study.
A recent study published in Nature Climate Change revealed that levels of hydrochlorofluorocarbons (HCFCs)—the damaging gases responsible for ozone depletion—peaked in 2021, five years ahead of previous projections. This decline highlights the efficacy of the Montreal Protocol, which aimed to phase out ozone-depleting substances used mainly in refrigeration, air conditioning, and aerosol sprays.
The phase-out of the most harmful chlorofluorocarbons (CFCs) by 2010 marked a significant milestone in protecting the ozone layer, which shields life on Earth from the Sun’s harmful ultraviolet rays.
The study utilized data from the Advanced Global Atmospheric Gases Experiment and the US National Atmospheric and Oceanic Administration to track pollutant levels. The results indicate that tighter national regulations and industry shifts, in anticipation of upcoming bans, have accelerated the decline of HCFCs.
Both CFCs and HCFCs are not only ozone-depleting but also potent greenhouse gases. Their reduction thus contributes to the broader fight against global warming. While CFCs can linger in the atmosphere for hundreds of years, HCFCs have a shorter lifespan of about two decades. Despite their decline, the residual effects of these gases will continue to impact the ozone layer for years to come.
The United Nations Environment Programme estimates that it could take four decades for the ozone layer to fully recover to its pre-1980s condition. However, the rapid decline in harmful gases provides a hopeful outlook on the power of coordinated global environmental policy.
