EnvironmentThe polar regions
The ozone hole and the Montreal Protocol
The world discovers a global problem and actually solves it
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The Montreal Protocol of 1987 has been ratified by every country in the world and is reckoned the most successful environmental agreement ever made. It succeeded because the problem was bounded, substitutes existed, and industry eventually saw an advantage in common rules. The comparison with climate negotiations is instructive precisely because the conditions were so different.
For children
Scientists discovered that the ozone layer over Antarctica was disappearing because of gases from refrigerators and spray cans. Within two years a treaty was agreed to stop using them — and the hole began to close.
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Part of Terra Saga — the story of Earth on a timeline. terrasaga.org