International commitments to protect the ozone layer are effective

There are also great victories on the environmental front, even if skepticism about the possible successes is fashionable. International commitments to protect the ozone layer are paying off, atmospheric concentrations of a family of harmful gases, HCFCs, have begun to decrease faster than predicted, according to a study. "It's a success and makes us optimistic that climate and environmental treaties can work," Luke Western, from the University of Bristol, lead author of the study, published in the scientific journal Nature Climate Change, told AFP. The Montreal Protocol, signed in 1987, is an international commitment concluded with a view to the gradual elimination of substances that deplete the ozone layer, used in refrigeration, air conditioning, spray foam and aerosols. This made it possible to eliminate the production of chlorofluorocarbons (CFCs), which were replaced by hydrochlorofluorocarbons (HCFCs), harmful to the ozone that protects us from UV rays and, at the same time, gases with a strong greenhouse effect. Their production and use is still being phased out. The international team behind the study showed, however, that the level of chlorine present in ozone-depleting HCFCs has already peaked in 2021, five years earlier than expected. The researchers relied on data from a network of specialized measuring stations, called AGAGE, as well as data from the US National Oceanic and Atmospheric Administration (NOAA).

"By establishing strict controls and promoting ozone-friendly alternatives, the protocol has succeeded in reducing atmospheric HCFC emissions and levels," said Luke Western. "Without the Montreal Protocol, this success would not have been possible, thus being a spectacular validation of multilateral commitments to combat the loss of the stratospheric ozone layer, with additional benefits in the fight against human-caused climate change," he stated. The protection of the ozone layer is often given as an example by scientists to illustrate the success of a collective action for the benefit of the environment. According to the latest quadrennial estimate of the United Nations Environment Program (UNEP), published at the beginning of 2023, the ozone layer should recover in the next four decades.