Dire warnings issued by the UN on 8 October regarding the potential impact of climate change are only likely to intensify the spotlight on the measures taken by commercial aviation to reduce its impact on the environment.

The UN Intergovernmental Panel on Climate Change (IPCC) report states that "limiting global warming to 1.5°C would require rapid, far-reaching and unprecedented changes in all aspects of society". It was released just days after key stakeholders in the aviation industry had gathered in Geneva to discuss progress towards implementation of ICAO's landmark Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA).

At that gathering – the Air Transport Action Group's (ATAG's) Global Sustainable Aviation Summit, which took place on 2-3 October – there had already been an acknowledgement that the clock is ticking for the industry.

ICAO Council president Olumuyiwa Benard Aliu told delegates in Geneva that "time is of the essence" in terms of aviation stakeholders putting standards into action.

Under ICAO's CORSIA scheme, airlines across the world are required to begin monitoring fuel use and CO2 emissions on international flights from 1 January 2019, with regulation of domestic flights still covered by national governments.


Successfully reaching the 1 January monitoring milestone is likely to be one of the scheme’s more straightforward goals. Contentious decisions still need to be made regarding which emissions units and fuel will be eligible under the CORSIA scheme, and on verification requirements. The aim is to have them in place by the ICAO Assembly that is due to take place in late 2019, before the CORSIA's carbon offset requirements come into force in 2021 for those covered by the scheme's initial voluntary phase.

"The goal here will be to have accredited verification bodies in place by early 2020, when airline operators' Emissions Reports will need to begin to be submitted," Aliu states.

Michael Gill, ATAG's executive director, told the same event that stakeholders "must continue to ensure that governments are also ready to play their role as authorities: signing off on emissions monitoring plans, implementing a national regulatory framework and receiving the emissions reports when they are delivered".

Gill continues: "More work needs to be done in many parts of the world. More work is also needed at ICAO, with decisions on key aspects of the emissions units for CORSIA compliance to be made in the coming months."

Alexandre de Juniac, director general of IATA, told delegates that "with hard work and solid commitment of industry and government, carbon-neutral growth from 2020 will be a reality. And we are already looking beyond. By 2050 we will cut our net emissions to half 2005 levels".

Indeed, most stakeholders continue to acknowledge that CORSIA alone cannot deliver a sufficient reduction in emissions.


During his speech, Aliu highlighted the important role of aircraft technology, ATC and operational improvements, and sustainable fuels in reducing emissions.

De Juniac, meanwhile, also suggested that "progress in technology, operations, and infrastructure – especially air traffic management – will match or better our fuel efficiency achievements of the past decade… The industry is ready for the next step-change in technology in the 2030s: hybrid and electric planes, and the large-scale rollout of sustainable fuels".

Stakeholders are keenly aware that the industry's progress is being closely monitored, and that many bodies already believe emissions initiatives do not go far enough. Some have even questioned whether a scheme such as CORSIA – which only seeks to offset growth in emissions – should include the word "reduction" in its title.

For an industry expecting thousands of new aircraft to enter service in the next 20 years, the questions are only likely to get more pressing.

“EU aviation emissions increased 96% from 1990 to 2016, and are now 3.6% of [total] EU emissions,” said a coalition of three NGOs with a focus on aviation and the environment – Transport & Environment, Aviation Environment Federation, and Carbon Market Watch – in a mid-September letter to the European Commission.

“Environmental safeguards in the CORSIA have been progressively weakened since 2016,” they claim, urging the Commission to avoid a hasty abandonment of its own EU Emissions Trading System (ETS) when CORSIA is introduced.

The NGOs believe ending the EU ETS could be in contravention of bloc's commitments under the 2015 Paris Agreement, which prohibit a “backsliding in ambition”.

They suggest that CORSIA is a weaker scheme than the EU ETS – which currently only covers flights within the European Economic Area – particularly due to its reliance on carbon offsets versus the latter’s focus on carbon allowances.


IATA, however, has consistently expressed a desire for airlines to work with a single scheme, rather than a combination of the international CORSIA initiative and existing or planned regional programmes.

"We are working with governments to prevent actions that undermine the agreement, such as the unilateral implementation of environmental taxes," says de Juniac in Geneva. "The ICAO Assembly next year provides an opportunity for governments to reaffirm CORSIA as the single global measure for aviation climate mitigation. It’s a top priority for CORSIA to be effective."

It remains unclear whether the EU ETS will eventually be superseded by CORSIA. The EU's scheme was created to cover any flights that touch airports within the EEA, but the international dimension has been put on hold while ICAO is working towards the CORSIA initiative.

Earlier, this year, several European member states expressed concerns that requirements around CORSIA were being watered down, risking the scheme's ability to have a meaningful impact on the environment.

In many cases they expressed a preference for measures that go further than those planned under the ICAO scheme.

Nevertheless, Gill said in Geneva that CORSIA can play a key role in the tackling of climate change: "This is the first time any global system like this has been attempted and, despite lots of detailed questions arising, I am confident that the industry is on track to meet its obligations."

CORSIA ultimately envisages aviation achieving carbon-neutral growth for international flights from 2020 onwards. A global emissions baseline will be created based on an average of 2019 and 2020 levels, then the first tranche of airlines will then be required to offset any growth beyond that baseline in the scheme’s voluntary phase between 2021 and 2026. The requirement becomes compulsory in 2027 for all carriers in ICAO member states.

Source: Cirium Dashboard