The purple and blue show where there is the least ozone, and the yellows and reds are where there is more. I think it would have been quite apocalyptic really, and it would have been a problem all over the world." In 1985, three scientists from the British Antarctic Survey published a study in the journal Nature finding abnormally low ozone levels in the southern hemisphere, in what came to be known as a "hole" in the ozone layer. It was only two years after scientists sounded the alarm on the ozone layer that dozens of countries signed up to the Montreal Protocol and eventually got the whole world on board. "The ozone layer problem was simpler than the climate problem.

Source: CNN August 19, 2021 13:11 UTC