https://en.wikipedia.org/wiki/Montreal_Protocol https://en.wikipedia.org/wiki/Montreal_Protocol The world decided for once that something had to be done and ..

https://en.wikipedia.org/wiki/Montreal_Protocol https://en.wikipedia.org/wiki/Montreal_Protocol The world decided for once that something had to be done and ... just did it. This allowed the ozone layer to gradually recover. The ozone hole will hopefully finally be closed again around 2050. (No source at hand, but read it a few days ago)