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How did the discovery of the Antarctic ozone hole influence international action?

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ozone depletion — Ozone depletion The Antarctic ozone hole reaches its maximum extent in October of each year. On October 7, 2021, when this image was captured, the Antarctic ozone hole spanned 24.8 million square km (9.6 million square miles).

The discovery of the Antarctic ozone hole in 1985 served as critical validation for earlier scientific theories regarding the impact of chlorofluorocarbons (CFCs) on the ozone layer. This finding provided the necessary momentum to transform international concern into concrete policy.1

Shortly before the discovery was published, nations had already begun discussions at the Vienna Convention for the Protection of the Ozone Layer, which established a framework for cooperation. The confirmation of the hole empowered the United Nations Environment Programme to lay the groundwork for the Montreal Protocol, which was adopted in 1987.1

This treaty mandated the phase-out of ozone-depleting chemicals, including CFCs and halons. The protocol is widely credited with the substantial decrease of these substances in the atmosphere, and scientists now observe clear signs of the ozone layer's recovery, with the Antarctic hole expected to return to 1980 levels by the 2060s.12