Industrial chemicals damage the climate and ozone layer

(CONNECT) In an international study led by them, researchers at the Swiss Federal Laboratories for Materials Science and Technology (Empa) have used global measurements to show that the ozone layer will fully recover seven years later than previously assumed. As Empa summarizes in a press release, feedstock chemicals such as carbon tetrachloride or certain chlorofluorocarbons (CFCs) are responsible for this. Their use in everyday products such as refrigerators and foams was banned worldwide as a result of the Montreal Protocol, which was negotiated in the 1980s and later tightened, because they damage the ozone layer.

However, these feedstock chemicals are still used in industrial processes as starting materials for modern refrigerants and plastics. However, the study now shows that the quantities produced and leakage rates were significantly underestimated, and therefore also the consequences: Not only the 0.5 percent of the amount produced that was forecast by the industry at the time escapes into the atmosphere, but 3 to 4 percent in each case. The emission rates for carbon tetrachloride, which is particularly harmful to the ozone layer, are even higher than 4 percent. These new findings are based on global atmospheric measurements from international networks such as the Advanced Global Atmospheric Gases Experiment, which also includes the Empa measuring station on the Jungfraujoch.

In addition, the use of these chemicals has not decreased as predicted, but increased, namely by 160 percent since the year 2000. This is due to a rapidly growing use in the polymer industry, for example for the production of fluoropolymers such as Teflon or polyvinylidene fluoride, an important material in lithium-ion batteries for electric cars. "These substances not only deplete the ozone layer, but are also highly damaging to the climate," Stefan Reimann, atmospheric researcher at Empa and lead author of the study, is quoted as saying.

If emissions remain at today's level, the stratospheric ozone layer would not fully recover until around 2073. According to the researchers, the uncertainty range of this estimate extends from six to eleven years. "The Montreal Protocol was successful because science, politics and industry worked closely together," summarizes Reimann. "This kind of cooperation is once again crucial for tackling new challenges." ce/mm