The Montreal Protocol of 1987 is rightly held up as a triumph of international environmental cooperation. But a new study asks: could we have acted even sooner?
Chlorofluorocarbons — CFCs, once common in aerosol cans and refrigerants — were identified as ozone-destroying chemicals in 1974. Bans rolled out within years. The Antarctic ozone hole, discovered in 1985, accelerated the timeline further, leading to the global agreement to phase out CFCs everywhere.
Researchers at MIT led by Jian Guan wanted to know whether modern scientific tools could have detected the ozone problem earlier. Their answer: probably yes. With today’s atmospheric monitoring and modeling capabilities, the signal of ozone depletion might have been picked up before CFCs were even widely deployed.
It’s an interesting counterfactual. The world did eventually act, and the ozone layer is recovering. But the study suggests the early warning signs were there — we just lacked the instruments to read them.
There’s a parallel to modern environmental monitoring. As climate sensors and satellite technology improve, we’re getting better at detecting problems before they become crises. The question is whether we’ll act on those signals as effectively as the world did on CFCs.
