This blog was written by Mandy Beck, an LLM in Environmental Law and Sustainable Development student at UWE Bristol.
Today, an airplane takes off approximately every 0.8 seconds somewhere around the globe. The impact of the aviation sector on the climate is enormous. Stefan Gössling, professor for sustainable transport at Lund/Linnaeus University, Sweden, even states that ‘on an individual level, there is no other human activity that emits as much over such a short period of time as aviation’. Globally, the aviation sector contributes a total of 2.5% to all anthropogenic CO2 emissions, making it a significant contributor to global warming. Often undiscussed, however, are the non-CO2 effects, meaning those effects resulting from e.g. particles, water vapour, and nitrogen oxides. Together with these non-CO2 effects, aviation contributes to global warming by 5%.
The International Air Transport Association estimates that the demand for flights is going to double by 2037. The decision-makers in the aviation sector thereby face the challenge of making aviation climate-neutral. In 2012, former European Commissioner for Climate Action in the European Commission, Connie Hedegaard stated that the ‘Polluter pays is the only principle that can limit aviation emissions’.
The Polluter Pays Principle (PPP) reflects an idea that is taught to us since our childhood: ‘Clean up after yourself’. Due to this principle, the costs of pollution should be allocated to the actor who caused them. The PPP is implemented by using market-based measures (MBMs), such as levies, emission trading (such as the EU Emission Trading System EU-ETS), and offsetting schemes. Implementing a MBM is necessary, as technical progress and operational measures alone will not be sufficient to limit climate emissions sufficiently in the aviation sector in the near future.
The first international offsetting scheme for aviation, CORSIA, will be implemented step by step starting 2021. Doubts, however, remain as to the effectiveness of this MBM in the light of reaching the goals of the Paris Agreement. Overall, the PPP could hold more potential in curbing aviation-caused climate emissions. The following improvements must, however, be made:
Inclusion of non-CO2 effects and removal of subsidies
Climate damages resulting from non-CO2 effects must be included in a MBM. Despite the major importance of non-CO2 effects, these effects are not included in CORSIA nor the EU-ETS. Secondly, the subsidies in the billions granted to airlines must be removed (e.g. grants for Etihad Airlines by Abu Dhabi; grants by the European Commission to Air Malta). Subsidies have an opposite effect than the PPP, as they falsify the costs that must be borne. Also, due to subsidies, aviation has a competitive advantage over other – more sustainable – means of transport.
Full payment for all environmental costs until 2050
The polluter must fully pay for all environmental costs by 2050 to reach the 1.5°C Goal (2085 at the latest for the 2°C Goal). The price for one ton of CO2 in 2019 including all climate costs (CO2 and non-CO2 effects) is 371 Euro/ton CO2. The price set under the EU-ETS today is much lower at approx. 30 Euro/ton CO2.To achieve the goals of the Paris Agreement, the PPP can be implemented gradually (with increasing CO2 prices over time), however, the above-mentioned full payment to the given deadlines must be reached.
Implementation of the PPP at the beginning of the value chain
Currently, all MBMs that have been implemented address the airlines. However, making the fuel suppliers pay for subsequent environmental damages, holds one significant advantage: fossil fuel suppliers would lose their competitive advantage, due to not paying for climate damage, over renewable energy providers. If all suppliers include environmental damage in their pricing, the market conditions would be equal.
Statista, ‘Number of flights performed by the global airline industry from 2004 to 2020’ (2020) <www.statista.com/statistics/564769/airline-industry-number-of-flights/> accessed 24 February 2020.
 Arthur Sullivan, ‘To fly or not to fly? The environmental cost of air travel‘ (2020) <https://www.dw.com/en/to-fly-or-not-to-fly-the-environmental-cost-of-air-travel/a-42090155> accessed 24 June 2020.
 Umweltbundesamt, Umweltschonender Luftverkehr: lokal – national – international (Umweltbundesamt Publikationen, 2019), 30.
 Malte Niklaß, Benjamin Lührs, Robin Ghosh, ‘A Note on How to Internalize Aviation’s Climate Impact of non-CO2 Effects’ <www.researchgate.net/publication/311788948_A_Note_on_How_to_Internalize_Aviation%27s_Climate_Impact_of_non-CO2_Effects> accessed 15 Mai 2020; equal conclusion reached in Jörg Larsson, Simon Matti, Jonas Nässén, ‘Public Support for aviation policy measures in Sweden‘ (2020) <https://doi.org/10.1080/14693062.2020.1759499> accessed 20 August 2020.
 IATA, ‘Annual review 2019’ (2019) <https://www.iata.org/contentassets/c81222d96c9a4e0bb4ff6ced0126f0bb/iata-annual-review-2019.pdf> accessed 11 February 2020,16.
 The Guardian, ‘Polluter pays’ is the only principle that can limit aviation emissions’ (2012) <https://www.theguardian.com/environment/2012/apr/04/polluter-pays-aviation-emissions> accessed 15 February 2020.
 David Boyd, ‘Clean up after yourself’ <www.theglobeandmail.com/opinion/clean-up-after-yourself/article773567/> accessed 10 February 2020.
 Philippe Sands, Jacqueline Peel, Adriana Fabra, Ruth MacKenzie, Principles of International Environmental Law (Cambridge University Press, 2018) 240.
 ICAO, Environmental Report 2019 – Chapter: Climate Change Mitigation: CORSIA (ICAO Publications 2019) 236.
 Carbon Offsetting and Reduction Scheme for International Aviation.
 That is holding the increase in the global average temperature to well below 2°C above pre-industrial levels.
 Stefan Gössling, Frank Fichert, Peter Forsyth, ‘Subsidies in Aviation’ (2017) 9(8) Sustainability 1295, 1295.
 Umweltbundesamt, Methodenkonvention 3.0 zur Ermittlung von Umweltkosten Kostensätze Stand 02/2019 (Umweltbundesamt Publikationen, 2019). UBA recommends the use of a multiplier of 2.0 for the transfer of the CO2 price to aviation emissions to include the non-CO2 effects.
 Michael Holder, ‘EU carbon prices surge to 14-year high’ <www.businessgreen.com/news/4017770/eu-carbon-prices-surge-14> accessed 23 July 2020.