Screen shot of two social media posts, the second responding to the first. Matt Walsh Remember when they spent years telling us to panic over the hole in the ozone layer and then suddenly just stopped talking about it and nobody ever mentioned the ozone layer again? Derek What happened is scientists discovered chlorofluorocarbons were bad for the ozone, countries believed them, the Montreal Protocol was signed, and CFC use fell by 99.7%, leading to the stabilization of the ozone layer, perhaps the greatest example of global cooperation in history.