NASA’s annual record doesn’t show much improvement (http://ozonewatch.gsfc.nasa.gov).
New Refrigerant Gases Also Harm Ozone Layer
A class of chemical refrigerants that replaced chlorofluorocarbons (CFCs) in past decades because they were believed not to damage Earth’s ozone layer has been found to inflict a small but measurable depletion of stratospheric ozone.
The ozone hole is believed to be gradually healing thanks to a global ban on the production of CFCs.
But a new NASA study says the hydrofluorocarbons (HFCs) now in use are not only a strong greenhouse gas, but they are also weak ozone-depleting substances.
“We are not suggesting HFCs are an existential threat to the ozone layer or to ozone hole recovery, but the impact is not zero as has been claimed,” said NASA’s lead study author Margaret Hurwitz.