By Dena Adler

 Photo Credit: NASA

The International Civil Aviation Organisation (ICAO), the UN specialized body for aviation, earned international praise in October 2016 for striking a deal to cap emissions from international passenger and cargo flights at 2020 levels, but a new Sabin Center Working Paper argues that ICAO must improve its transparency to truly “take-off.” Given the hurdles to achieving international cooperation, ICAO deserves kudos for developing its Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA), the program that aims to put the brakes on emissions from aviation—a sector responsible for approximately 5% of man-made radiative forcing. The Environmental Defense Fund estimates that if effective the program could offset 2.5 billion tonnes of carbon dioxide between 2021 to 2035. However, first the program must achieve lift-off. What additional efforts could help launch its success?

In a new Sabin Center Working Paper, legal consultant, Aoife O’Leary, argues that for starters, CORSIA must significantly improve its governance structure and transparency. Otherwise, it will risk being perceived as illegitimate by the public. In her paper, she evaluates whether CORSIA would pass muster under the Aarhus Convention—an international treaty that grants the public rights of access to information, participation in decision-making, and access to justice in environmental matters. Applying the Aarhus Convention, she finds that ICAO must allow public participation and transparency as the details of CORSIA, especially biofuel and offset standards, are determined. In addition, O’Leary explains why the EU is obligated to publicly disclose any CORSIA documents and exposes uncertainty regarding whether the implementation of CORSIA into EU law will be in compliance with the Aarhus Convention. Read the complete Sabin Center Working Paper to learn more.


  1. Good paper on an important subject. However, it would be helpful to also focus on the environmental integrity of whatever the schemes is, not just how it is made. CORSIA is an offsetting scheme and as such need to demonstrate robustness and integrity. The CDM unfortunately was undermined partly because offsets were issued that should not have been. There was no effective way to remove these ‘bad offsets’ since the liability was placed on the verifiers who simply said they would not continue to verify if they had any liability imposed.

    Fortunately the California scheme had the benefit of learning from the mistakes of CDM and has placed the liability for ‘bad offsets’ on the buyers or owner of those offsets. This means that offsets that are lacking in environmental integrity can be invalidated without undermining the wider market.

    Unless CORSIA has such mechanisms to ensure the environmental integrity of the offsets being created, then the whole initiative will, quite rightly, fail.

  2. I wonder if the author understands how the ICAO process works and the reasons for it.

    First, ICAO’s primary focus is safety and security. Anything beyond safe and secure is frosting on the cake, so to speak. As a result, ICAO requires that people working in the technical working groups provide credentials proving their technical expertise. One might argue whether that’s necessary for environmental matters, but that point is that ICAO has a very good reason for only allowing experts in.

    Second, and almost setting aside any arguments on whether technical experts actually should be required to be technical experts, ICAO does have transparency. The Standards and Recommended Practices that are developed by the technical working groups and approved within ICAO are submitted to States for comment and approval. So to repeat, whatever technical recommendations are created by ICAO all 191 ICAO Member States get to see them and comment on them.

    So the article seems to miss the point a bit by saying that the process isn’t transparent. I don’t think that’s accurate, and I suspect that anyone with experience working at ICAO would agree with that.

  3. In response to the comment by Dan I would agree that ICAO’s primary focus should absolutely be safety and security and in those committees the need to ensure that the experts are really technical experts is evident. However, when we are talking about environmental measures then there is less need for such restrictions and it also means that ICAO misses out on huge technical experts from around the world. Further, in terms of environmental decision-making, the Aarhus Convention provides for certain standards of public participation and transparency not upheld at ICAO. The Convention does not deal with safety and security issues for good reason – those discussions often should be private. However, if ICAO cannot adapt to an appropriate set of procedures to deal with environmental issues then perhaps those issues are best dealt with in another forum. As you rightly point out, the point of ICAO is to secure safety and security, protecting the environment is nowhere near one of ICAO’s main aims.

    In response to Julestheski, I absolutely agree re the environmental integrity but sadly there was only so much time and space in this paper. Interesting take from California. The EU just decided to ban ‘bad offsets’ from the scheme entirely (and from 2020 won’t use all offsets at all).

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