In 1928 an invention first produced in Germany quickly became commonplace across the world.
Chlorinated fluorocarbons (CFCs) were used in everything over the next few decades. Think things like polystyrene cups, refrigerators, and aerosol sprays.
Little did we know at the time, but those CFCs were burning a hole in the Earth's ozone layer. It wasn't until the 70s that we finally cottoned on.
You see, the ozone layer is like the Earth's sunscreen. It blocks about 99 percent of UV radiation.
So you know how it takes you a good 20 minutes to get a touch of pink in the sun? Yeah, we're talking sunburnt in seconds.
But it was worse than that.
In the 1970s, scientists realised that the ozone layer was being depleted by the growing use of chlorofluorocarbons (CFCs).— The Conversation (@ConversationUK) August 18, 2021
Thanks to the Montreal Protocol, the world phased out CFCs.
A team of experts simulated two worlds - one without the Protocol ⬇️ 🧵 pic.twitter.com/DBPQ0l5weE
The ozone's decline had humans looking down the barrel of a world crisis. We would have seen an increase in cancers, blindness, metabolic disorders and a decline in our immune systems and oceanic productivity. UV rays also affect plant growth, so it would have reduced our ability to grow food.
It was bad — real bad.
So in 1987, the nations of the world got together and decided to ban the production of CFCs, establishing the Montreal Protocol on ozone-depleting substances. It was the first international treaty to be signed by all countries of the world, and is considered the greatest environmental success story in the history of the United Nations. World leaders moved quickly and effectively. There was 50 years of damage to undo so this was by no means a quick fix, and the hole got bigger before it got smaller but it did start to get smaller. Now, it's tracking towards a full recovery.
The UN reports that with the current momentum the ozone layer will be completely healed as far as some regions of the planet are concerned, by the 2030s.
We did that. Humans did that.
We fixed a problem that felt unfixable. So now we need to do that again, but we have to move quickly.
The recent IPCC climate change report aptly described itself as a 'red code for humanity.' It warned that under the current emissions policies we would not be able to limit the life-altering effects of global warming to 1.5 degrees by 2050, as was hoped.