The rise has been attributed to an increase in the use of the chemicals, known as chlorofluorocarbons (aka CFCs), that are used to make other ozone-friendly alternatives to CFCs. Prior to their ban, the chemicals were used in the manufacture of aerosol sprays; blowing agents for foams and packing materials; as solvents, and as refrigerants.
The Montreal Protocol is an international treaty signed in 1987 designed to protect the ozone layer by phasing out the production of numerous substances that are responsible for its depletion. It includes an exception that continues to allow the use of the CFCs when used to create alternative chemicals.
Dr Luke Western, lead author on the study, said: “We’re paying attention to these emissions now because of the success of the Montreal Protocol. CFC emissions from more widespread uses that are now banned have dropped to such low levels that emissions of CFCs from previously minor sources are more on our radar and under...