Remember the hole in the ozone layer? It was discovered back in the 1980s, caused by Chlorofluorocarbons (CFCs) in all kinds of consumer products. Back in 1987, a number of governments ratified the Montreal Protocol in order to help combat the problem. Since then, we’ve done a lot to phase out CFCs, and it’s finally starting to have an impact.
The ozone layer helps to protect the Earth from the harmful effects of the sun’s light, namely the ultraviolet light that can cause skin cancer and cataracts–so fixing the ozone was deemed pretty important. In the meantime, though, we’ve discovered a lot of other environmental issues that have stolen the limelight from the ozone hole. A lot of people have probably forgotten that it was ever a problem.
Luckily, scientists haven’t forgotten, and they’ve been monitoring the hole to see how the healing process is going. For a long time, as recently as 2015, it seemed like the hole wasn’t getting any bigger; but recent research shows that it’s forming later in the year, which is a good sign, and that some of the previous readings could have been anomalous. How is that? Well, volcanic eruptions can deplete the ozone too, meaning that the hole can be bigger or smaller from year to year. But the overall trend is towards healing.
The Montreal Protocol was a big moment, where a lot of countries came together to work on environmental issues. But even as we phased out CFCs, a lot of products started using HFCs instead. And while those don’t deplete the ozone, they are still greenhouse gasses, and do still contribute to global warming.
Overall, it’s a bit of a mixed bag, but we know more now. And when we finally get around to dealing with other environmental issues, like global warming, we can plan ahead a little better.