The Montreal Protocol and the Kigali Amendment
The 1987 treaty that phased out the chemicals eating the ozone layer; its 2016 Kigali Amendment now also cuts a climate gas.
What the paper can ask
- Signed 16 September 1987, in force 1 January 1989; 16 September is World Ozone Day.
- Ratified by 198 parties, the first UN treaty with universal ratification. (as of 23 Oct 2026)
- The substitutes that replaced ozone-depleting gases turned out to be powerful greenhouse gases; the Kigali Amendment phases them down.
- The Kigali Amendment was adopted on 15 October 2016 and came into force on 1 January 2019.
- India's phase-down under Kigali starts with a 10 percent cut in 2032. (as of 23 Oct 2026)
Why exams ask
Setters pair the treaty with its amendment, its parent convention, the gases each covers and India's phase-down dates.
The full story
The Montreal Protocol was signed on 16 September 1987 and came into force on 1 January 1989. It phases out CFCs, halons and HCFCs, the gases that thin the ozone layer. It is a protocol under a 1985 framework treaty on the ozone layer. It is the only UN treaty ratified by every country.
In the news
Test yourself
1.The Montreal Protocol (1987) deals with:
Correct. The Montreal Protocol phases out CFCs and other ozone-depleting substances; the 2016 Kigali Amendment added hydrofluorocarbons (HFCs).
Not quite. The Montreal Protocol phases out CFCs and other ozone-depleting substances; the 2016 Kigali Amendment added hydrofluorocarbons (HFCs). It goes into your error book.