The 1989 Montreal Protocol to phase out ozone-destroying chlorofluorocarbons (including End-Permian gases like methyl bromide) is widely acknowledged to be the most successful environmental international agreement ever. But failure was never really an option. NASA simulations of the planet under a business-as-usual emissions scenario for these chemicals showed the ozone layer almost disappearing from the planet entirely by the 2060s, an unimaginable situation that would have doubled UV radiation at the planet’s surface and spawned a global wave of lethal mutations and cancers.
