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Climate Action

Reducing emissions from aviation

Aviation is one of the fastest-growing sources of greenhouse gas (GHG) emissions. The EU is taking action to reduce aviation emissions in Europe and working with the international community to develop measures with global reach.

Aviation emissions

Aviation is a highly energy-intensive sector. For example, a person flying from Lisbon to New York and back generates roughly the same level of emissions as an average EU citizen does by heating their home for a whole year.

In 2022, aviation contributed 2% to the global carbon dioxide (CO2) emissions, experiencing a faster growth rate in recent decades compared to rail, road, or shipping. According to the International Energy Agency (IEA), with the rebound of international travel post-COVID-19, aviation emissions for 2022 reached almost 800 Mt of CO2. This is approximately 80% of pre-pandemic emission levels.

The International Civil Aviation Organization (ICAO) forecasted that by 2050 international aviation emissions could triple compared to 2015. In 2022, direct emissions from aviation accounted for 3.8% to 4% of total EU GHG emissions. Aviation generates 13.9% of transport emissions, making it the second biggest source of greenhouse gas emissions in the transport sector, after road transport.

To address this trend, various technical and operational measures - such as the use of sustainable aviation fuels, improvements in airframes and engines, operational optimisations, a modal shift to less emission-intensive modes, including rail, and reducing the need for transport (e.g., through videoconferencing) - are essential to mitigate the growth of emissions, ultimately reducing them in the coming decade and contributing to the EU’s overall climate neutrality target.

In addition to CO2, aircraft engines release various other gases such as nitrous oxides (NOx), sulphur dioxide (SO2), water vapour, and particulate matter - including sulphate and soot. When these emissions occur at high altitudes, they impact the physical and chemical properties of the atmosphere. This contributes to the greenhouse effect, the main driver of climate change. These gases can lead to the creation of persistent contrail cirrus clouds, which also contribute to global warming by retaining the Earth’s heat.

As confirmed by a report from the European Aviation Safety Agency (EASA), the non-CO2 effects of aviation activities accounted for more than half (66%) of the sector’s net climate forcing in 2018.

EU action

All sectors, including aviation, need to contribute to achieving the EU’s ambitious climate targets. This is why, since 2012, the EU Emissions Trading System (ETS) has been covering the aviation sector in Europe.

In 2019, the EU launched the European Green Deal: our plan for Europe to become climate-neutral by 2050. To achieve that goal, we need to reduce transport emissions by 90% by mid-century (compared to 1990 levels).

Aviation in the EU Emissions Trading System

Under the EU ETS, all airlines operating in Europe, European and non-European alike, are required to monitor, report and verify their emissions, and to surrender allowances against those emissions. They receive tradeable allowances covering a certain level of emissions from their flights each year.

Under the EU ETS “cap and trade” system, aviation contributed to reducing the carbon footprint of other sectors by around 160 million tonnes during the third trading period (2013-2020), according to the 2022 European Aviation Environmental Report. The compliance rate in the aviation sector is high, as over 99.5% of emissions are usually covered by surrender of allowances.

The original legislation, adopted in 2008, was designed to apply to emissions from flights from, to and within the European Economic Area (EEA) – the EU Member States, plus Iceland, Liechtenstein and Norway. The European Court of Justice has confirmed that this approach is compatible with international law. The EU, however, decided to temporarily limit the scope of the EU ETS to flights within the EEA, to support the development of a global measure by the International Civil Aviation Organization (ICAO). This measure is known as Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA).

In light of the launch of CORSIA, this limitation has been extended several times. During the latest revision, it was extended one last time, until the start of 2027. By July 2026, the Commission will carry out an assessment of whether more action is required for flights to and from Europe, in line with criteria set in the EU ETS Directive. Subject to the outcome of this assessment, the Commission will make a legislative proposal that could extend the scope of EU emissions trading to departing flights and exempt incoming flights. Alternatively, the proposal could be to maintain the intra-European scope if CORSIA is strengthened and has a high level of global participation and implementation.

The EU also strives to reduce emissions from aviation via the Linking Agreement with Switzerland. The principles governing aviation activities in the Swiss ETS align with those of the EU ETS. Following the entry into force of the Linking Agreement, a Commission Delegated Decision exempted flights arriving from Switzerland from the EU ETS, reflecting the scope of aviation activities covered by the Linking Agreement. A Commission Decision ensured the corresponding changes of the free allocation to aviation operators. Moreover, under the 'one-stop shop' approach, aircraft operators are administered by either an EEA state or Switzerland for both emission trading systems. This means that a single authority takes responsibility for the implementation of the two systems so that operators will only have to interact with one authority under the linked systems.

Emissions from flights to the United Kingdom are covered by the EU ETS, as provided for by the Trade and Cooperation Agreement with the UK. Flights arriving from the UK were exempted in a Commission Delegated Regulation, similarly to flights arriving from Switzerland, as they are covered by the UK-ETS. Free allocation to aviation operators was also adjusted accordingly in a Commission Decision.

Revision of the EU ETS Directive concerning aviation

In July 2021, the European Commission adopted a series of legislative proposals setting out how it intends to achieve economy-wide climate neutrality in the EU by 2050. This includes an intermediate GHG emissions reduction target of at least 55% by 2030, compared to 1990 levels.

The revision of the EU ETS in aviation aims to ensure that the aviation industry contributes to the EU's climate objectives. This includes increasing the auctioning of allowances by phasing out free allowances and applying the strengthened linear reduction factor to aviation. Additionally, the revision appropriately implements ICAO's CORSIA through the EU ETS Directive. This will be applied to international flights departing from or arriving at airports within the European Economic Area (EEA). For flights within the EEA, only the EU ETS will continue to apply. The revision introduces the following changes:

Full auctioning from 2026

Free allocation to aircraft operators will be reduced by 25% in 2024 and by 50% 2025, moving to full auctioning for the sector by 2026. The free allocation for 2024 and 2025 will be distributed among aircraft operators proportionately to their 2023 verified emissions.

ETS-financed support for uplifting eligible alternative aviation fuels

20 million ETS allowances (EUR 1.6 bn at an allowance price of EUR 80) have been reserved to cover some, or all, of the price gap between conventional fossil fuels and eligible alternative aviation fuels uplifted from January 2024.

Levels of support can go up to 100% of the price difference for eligible fuel uplifted at small islands, small airports, and outermost regions. For uplift at other airports, renewable fuels of non-biological origin will receive a level of support of 95%, while it will be 70% for advanced biofuels and 50% for other fuels of non-fossil origin included in the scope of ReFuelEU Aviation. Only fuels used on flights covered by ETS compliance obligation will be supported. More information of the ETS-Financed support can be found in this presentation.

Monitoring, reporting, and verification (MRV) of non-CO2 effects

The Commission is establishing an MRV system for non-CO2 aviation effects to apply from 1st January 2025, calculating CO2 equivalent per flight through state-of-art approaches using flight information, aircraft and fuel properties, performance information and weather data. By the end of 2027, the Commission will deliver a report on the results and if appropriate, will make a legislative proposal to address non-CO2 effects of aviation.

Innovation Fund

5 million ETS allowances will be added to the Innovation Fund, which airlines and airports have always been eligible to access for support. The Innovation Fund can explicitly support the electrification of aviation, decarbonise the sector and mitigate its non-CO2 effects.

Transparency

The Commission will publish extended data on annual emissions from aviation activities. The first dataset was published for the 2022 reporting period.

The restriction of the geographical scope of the ETS is extended until the start of 2027

In 2026, the Commission will carry out an assessment of CORSIA to determine if it is sufficiently delivering on the goals of the Paris Agreement. The assessment will evaluate whether CORSIA has been strengthened and its level of coverage of international aviation emissions. Subject to the outcome of this assessment, the Commission will make a legislative proposal. This proposal could extend the scope of the EU ETS to include departing flights and exempt incoming flights, if CORSIA is not strengthened to be aligned with the Paris Agreement or the participation of third countries in it is insufficient.

Appropriate implementation of CORSIA through the EU ETS Directive

The Directive maintains the current EU ETS scope and applies CORSIA to extra-European flights only, as stronger action is being taken for intra-European flights. The basic premise of the Directive is that the same conditions must apply on the same routes. The eligibility of credits to be used for CORSIA offsets is subject to the participation of issuing countries in the Paris Agreement and in CORSIA, as well as a prohibition of double counting. These rules were adopted on 10 May 2023 and entered into force on 5 June 2023. You will find the legal text below:

Global scheme to offset emissions

The European Union has consistently emphasised its strong preference for a multilateral action to tackle emissions from aviation. In October 2016, ICAO agreed on a Resolution for a global market-based measure to address CO2 emissions from international aviation as of 2021. As a result, the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA) was introduced.

CORSIA aims to stabilise CO2 emissions at 2020 levels by requiring airlines to offset the growth of their emissions above these levels. Under CORSIA, aeroplane operators are required to:

  • Monitor, report and verify emissions on all international routes;
  • Offset the growth above the baseline in emissions from routes subject to offsetting in the scheme by purchasing eligible emission units generated by projects that reduce emissions in other sectors.

CORSIA is being implemented in three phases:

  • Pilot phase (2021-2023) - offsetting requirements are only applicable to flights between States that have volunteered to participate in CORSIA offsetting (115 States has volunteered to participate in 2023).
  • First phase (2024-2026) - offsetting requirements will still be applicable only on routes between volunteering States.
  • Second phase (2027-2035) - CORSIA should apply to all ICAO contracting states, with certain exemptions.

EEA countries have implemented the scheme for airlines based in the EEA, through the EU ETS Directive. A regular review of the scheme is required under the terms of the agreement. This should allow for continuous improvement, including in how the scheme contributes to the goals of the Paris Agreement.

The CORSIA baseline of 2020 emissions was meant to be established as an average of reported emissions from 2019 and 2020. However, following the significant reduction of aviation activities due to the COVID-19 crisis, the baseline for the pilot phase was re-defined as the level of 2019 emissions. This, combined with the rebound of the aviation sector, resulted in no offsetting obligations under CORSIA for aeroplane operators in 2021 and 2022. The ICAO recovery scenarios show that this is expected to be the case for 2023 as well. After the first periodic review of CORSIA, ICAO countries agreed on a new CORSIA baseline from 2024 onward, defined as 85% of CO2 emissions in 2019.

The 2023 revision of the EU ETS aviation rules extended the restriction of the EU ETS geographical scope until the start of 2027. After this date, departing flights from the EEA to states not implementing ICAO’s CORSIA scheme would be included in EU ETS. This is an incentive for third countries to apply the CORSIA scheme.

In October 2022, during the 41st ICAO Assembly, ICAO Member States adopted a collective long-term global aspirational goal (LTAG) of net-zero carbon emissions by 2050. The achievement of the LTAG will depend on the cumulative impact of numerous CO2 emissions reduction strategies, such as the rapid adoption of innovative aircraft technologies, simplified flight procedures, and greater production and use of sustainable aviation fuels.

Documentation

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FAQs

Questions & Answers

Questions and Answers on the inclusion of non-CO2 aviation emissions in the Monitoring, Reporting and Verification (MRV) framework 

Historic aviation emissions and the inclusion of aviation in the EU's Emission Trading System (EU ETS)

Aircraft operators

The aircraft operators list

Obligations and procedures for new entrants

Allocation of emissions allowances

Special reserve

Small emitters

Penalties & enforcement of the EU ETS - Aviation legislation

Extension of the EU ETS to the EEA EFTA states (Iceland, Liechtenstein and Norway)

Monitoring and reporting