Montreal Protocol on Substances that Deplete the Ozone Layer
- Date
- 16 September 1987
- Category
- Environment & climate
- Region
- Global
- Era
- Contemporary
- Significance
The Montreal Protocol is a landmark international environmental treaty adopted on 16 September 1987 in Montreal, Canada, to phase out the production and consumption of ozone-depleting substances such as chlorofluorocarbons (CFCs) and halons.
Building on the framework Vienna Convention of 1985, it was negotiated rapidly after scientists confirmed that these industrial chemicals were thinning the stratospheric ozone layer and had created a seasonal "ozone hole" over Antarctica. The agreement entered into force on 1 January 1989 and was subsequently strengthened by amendments in London (1990), Copenhagen (1992), Montreal (1997), Beijing (1999), and Kigali (2016), the last of which extended controls to hydrofluorocarbons (HFCs) as potent greenhouse gases. Featuring binding, time-bound targets and a multilateral fund to assist developing nations, the Protocol became the first treaty in United Nations history to achieve universal ratification by all member states. It is widely regarded as the most successful international environmental agreement, having eliminated roughly 99 percent of controlled ozone-depleting chemicals and placing the ozone layer on track to recover to 1980 levels by the mid-21st century.
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Empires active in 16 September 1987
- Soviet Union1922 CE – 1991 CE
- British Empire1583 CE – 1997 CE
- Portuguese Empire1415 CE – 1999 CE
- Yugoslavia1918 CE – 1992 CE
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- The Rio Earth Summit3-14 June 1992
- The Sahel Drought Triggers Mass Famine Across West Africa1972–1974
Further reading
The wider story
A New Green History of the World
The classic accessible account of how environment and climate have shaped human history.
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