The Montreal Protocol
Big idea: The Montreal Protocol (1987) is widely considered the most successful international environmental agreement, achieving near-universal participation and measurable results.
Key features
- Signed: 1987; entered into force 1989
- Participation: 198 countries — universal ratification (only UN treaty to achieve this)
- Targets: Phase-out schedules for ODS production and consumption
- Differentiated responsibility: Developing countries given longer timelines
- Multilateral Fund: Financial support for developing countries to transition
- Amendments: Strengthened multiple times (London, Copenhagen, Kigali)
Phase-out timeline
- CFCs: Phased out by 1996 (developed), 2010 (developing)
- Halons: Phased out by 1994 (developed), 2010 (developing)
- HCFCs: Being phased out by 2030 (developed), 2040 (developing)
- HFCs: Added in Kigali Amendment (2016) — also greenhouse gases
The Kigali Amendment (2016) added HFCs to the Montreal Protocol. HFCs dont harm ozone but are powerful greenhouse gases — so this also helps climate!
Exam tip: Questions often ask you to evaluate the Montreal Protocols success. Know both its achievements AND its limitations.
Evaluating the Montreal Protocol
Big idea: The Montreal Protocol has achieved remarkable success but also has limitations. It offers lessons for addressing other global environmental problems like climate change.
Successes
- >99% reduction in ODS production and consumption
- Ozone recovery: Hole stabilised and beginning to shrink
- Universal participation: All 198 UN members ratified
- Effective compliance: Few violations; strong monitoring
- Co-benefits: Avoided significant climate warming (CFCs are also GHGs)
- Technology transfer: Helped developing countries access alternatives
Limitations and challenges
- Slow recovery: Full recovery not expected until 2066 due to CFC persistence
- Illegal production: Some CFC smuggling still occurs
- Replacement problems: HCFCs and HFCs have their own issues (GHGs)
- Not transferable: Success factors may not apply to climate change
Why was it successful? (Lessons for climate)
- Clear scientific consensus on the problem
- Alternatives were available (industry could adapt)
- Relatively few major producers to regulate
- Costs concentrated in specific industries, not whole economy
- Strong financial support for developing countries
- Regular strengthening based on new science
Exam tip: Comparing Montreal Protocol (success) with Kyoto/Paris (challenges) is a common essay topic. Explain why ozone was easier to address than climate.