The International Civil Aviation Organization (ICAO) reached a historic agreement at its 39th Assembly last month in Montreal when member states voted to tackle airline greenhouse gas emissions and to commit to carbon neutral growth, starting in 2021.

A global market-based measure (GMBM) will be established to control emissions from international aviation, a key part of which will be ICAO’s Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA).

As part of the scheme, increases in CO2 emissions from the aviation industry will be offset against activities such as sustainable alternative fuels, efficient aircraft technologies, tree planting and alternative energy projects.

A pilot phase will run from 2021 to 2023, with a voluntary first phase from 2024 to 2026 and the second phase from 2027.  At the assembly, states representing more than 83% of international flight operators volunteered to participate in the scheme from 2021.