ICAO's market-based measure

An interactive tool to see how additional countries' support for CORSIA can boost coverage of international aviation emissions.

The International Civil Aviation Organization (ICAO), the UN body that sets standards for international flights, has a goal of "carbon neutral growth from 2020" — i.e., limiting the net emissions of international flights to year-2020 levels. With enormous growth projected for this sector, that's a significant gap to close.

Better air traffic management and operational improvements; new technologies and standards for more efficient aircraft; lower-carbon alternative fuels — all, in principle, can help close the gap. Governments, industry and NGOs agreed on the crucial role of a global market-based-measure, under which airlines purchase high-quality emissions reductions to offset emissions above 2020 levels, prompting ICAO to adopt the Carbon Offsetting and Reduction Scheme for International Aviation, or CORSIA, in 2016.

Under the CORSIA Resolution [PDF]:

  • From 2021-2023, States will opt in to a voluntary pilot phase
  • From 2024-2026, States will opt in voluntarily to another phase
  • From 2027-2035, States will participate if they have an individual share of international aviation activities in revenue-tonne-kilometers (RTKs) in year 2018 above 0.5% of total RTKs or if their cumulative share in the list of States from the highest to the lowest amount of RTKs reaches 90% of total RTKs
  • Least developed countries, land-locked developing countries, and small island developing countries will all be exempt throughout
  • Exempt States and States not covered, could opt in if they so choose

Explore emission reduction scenarios

Below, we've checked the boxes of all States that have signaled they are likely to join from the beginning, starting in 2021. Bars indicate the amount of forecasted cumulative emissions above 2020 levels this participation could be expected to cover in the voluntary phase, the mandatory phase, and the combined phases (from 2021-2035)1.


[1] Boeing Current Market Outlook 2016-2035 (The Boeing Corporation, 2016); "Aviation Carbon Footprint: Global Scheduled International Passenger Flights" – 2012; "PRESENT AND FUTURE TRENDS IN AIRCRAFT NOISE AND EMISSIONS" (ICAO, 2013); "Present and Future Trends in Aircraft Noise and Emissions" (ICAO, 2016)

[2] "Eleven ICAO LTF (Long Term Forecast) Regions," ICAO Document APANPIRG/25 - WP/17 APPENDIX C: ICAO LTF REGIONS USED FOR ANALYSIS AND FOR PUBLICATION (Passenger Traffic) (International Civil Aviation Organization, September 2014)