Atmospheric HCFC levels may have peaked

Scientists have observed a significant drop in the levels of hydrochlorofluorocarbons (HCFCs) in the atmosphere. The most common, R22, poses a significant threat due to being an ozone-depleting substance with a high global warming potential (GWP) 1760 times that of carbon dioxide.

A study led by the University of Bristol and published in scientific journal Nature Climate Change found that the peak amount of these chemicals occurred in 2021, five years earlier than predicted.

Although the decline since then is small, at less than one per cent, it is a positive sign that HCFC emissions are heading in the right direction, largely attributed to the successful implementation of the Montreal Protocol under which HCFC production has been phased out since 2010 with the aim of eliminating HCFC emissions entirely by 2040.

Leading the research, Dr. Luke Western, a Marie Curie Research Fellow at the University’s School of Chemistry, explained: “The results are very encouraging. They underscore the great importance of establishing and sticking to international protocols.”

Nevertheless, challenges remain; leaks from old appliances and foams continue to release HCFCs, requiring increased recycling efforts to prevent further damage. 

Also, as HCFCs are sometimes used as feedstock for other chemicals – a practice expected to continue for many years with inevitable accidental emissions – the exploration of alternative production methods is vital.

However, the study projects that the impact on ozone depletion and global warming by HCFCs will return to 1980 levels by 2082 for radiative forcing and 2087 for equivalent effective chlorine (EECl). 

Co-author Dr. Isaac Vimont, a research scientist at the National Oceanic and Atmospheric Administration, added: “This study highlights the critical need to be vigilant and proactive in our environmental monitoring, ensuring other controlled ozone depleting and greenhouse gases follow a similar trend, which will help to protect the planet for future generations.”