A study reveals that CFCs, which were banned in the 1980s, are starting to be used again because they destroy the ozone layer. However, it is unclear where and why it was used.
Thirty years after countries agreed to reduce the use of ozone-depleting chemicals, there are promising signs that ozone will fully recover by the 2060s. However, we are not over the danger yet. A study published this month in the journal Nature Geoscience shows that emissions of hazardous gases banned in the 1980s are increasing today, with implications not only for the ozone layer but also for climate change. Even more worrying is that we are not sure exactly what is causing some of these emissions to increase.
The group of ozone-depleting pollutants are called chlorofluorocarbons or CFCs, and they were previously widely used in refrigerants, air conditioners, aerosol cans and other applications. The Montreal Protocol, the international agreement that came into force in the late 1980s, required countries to phase out the use of these CFCs. The protocol is widely regarded as a historic achievement in addressing a thorny and global environmental problem.
In an email to Earther, lead author Luke Western, a researcher at the University of Bristol and the National Oceanic and Atmospheric Administration in the UK, told Earther that to understand the global status of CFC emissions, researchers need to use atmospheric measurements of CFCs and a study of how gases move around the world. He said they used models. CFC measurements were collected from stations around the world.
The study reveals that emissions from 5 different types of CFCs are increasing. Three of these CFCs have an explainable reason: a loophole in the Montreal Protocol that allows some emission of CFCs in the production of some hydrofluorocarbons (HFCs), which are largely CFCs replacement chemicals. While HFCs don’t do much damage to the ozone layer, they are potent greenhouse gases with alarming effects on global warming. In the meantime, it should be noted that the Biden administration signed a global amendment to the Montreal Protocol in September that will phase out the use of HFCs.
The research by Western and his team cannot concretely link emissions to a particular region or factory; but we can make some guesses. China has historically been the world’s largest producer of HFCs. A Honeywell factory located in Louisiana is also reportedly following China.
“We really have no idea. We don’t know of any chemical processes where these chemicals would emerge as byproducts,” Western co-author Martin Vollmer, an atmospheric chemist at the Swiss Federal Laboratories for Materials Science and Technology in Dübendorf, said at a press conference last month. “We hope to provide an early warning so that others are aware of these emissions.”