ICAO, the International Civil Aviation Organization, has announced that government, industry and civil society representatives have agreed on a new global market-based measure (GMBM) to control CO₂ emissions from international aviation. The historic move – a step towards the “global aspirational goal” of carbon-neutral growth from 2020 onwards – came on 6^th October as the Plenary Session of the UN aviation agency’s 39th Assembly agreed to recommend adoption of a final Resolution text for the GMBM.

ICAO’s Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA) is designed to complement these mitigation measures. Implementation of the CORSIA will begin with a pilot phase from 2021 through 2023, followed by a first phase, from 2024 through 2026. Participation in both of these early stages will be voluntary and the next phase from 2027 to 2035 would see all States on board.

Some exemptions have been accepted for Least Developed Countries (LDCs), Small Island Developing States (SIDS), Landlocked Developing Countries (LLDCs) and states with very low levels of international aviation activity.

All states with aircraft operators undertaking international flights are requested to compile and transmit aggregated emissions information of their operators to ICAO, as part of the activities included in the States' implementation of a monitoring, reporting and verification (MRV) system.

Aircraft are currently estimated to contribute about 3% of the total of the anthropogenic radiative forcing by all human activities. Total CO₂ aviation emissions represent approximately 2% of Global Greenhouse Emissions and this amount is expected to grow by around 3-4% per year in view of forecasted traffic growth of around 5% per year. Medium-term mitigation for CO₂ emissions from the aviation sector can potentially come from improved fuel efficiency, partially offsetting the growth of CO₂ aviation emissions.

In addition to market-based measures, other paths to reduced emissions include aircraft technologies such as lighter airframes, higher engine performance and new certification standards, operational improvements (e.g. improved ground operations and air traffic management), sustainable alternative fuels.