Emissions

The full-flight carbon dioxide (CO₂) emissions of all flights departing from EU27+EFTA airports have followed a similar pattern to noise and were estimated to be 133 million tonnes in 2023, which is 10% below the 2019 peak (

). Mainline and low-cost operators accounted for 52% and 28% of CO₂ emissions respectively in 2023 ( ). Single-aisle and twin-aisle jets emitted 96% of total CO₂ emissions (almost equally split between the two categories), while long-distance flights (above 4 000 km) represented 46% ( ). Flights with a destination outside EU27- EFTA accounted for 61% of CO₂ emissions ( ).

In the short term, market-based measures are expected to stabilise European aviation’s net (i.e. lifecycle) CO₂ emissions, while sustainable aviation fuels still show the greatest potential for reduction in the 2050 timeframe (Figure 1.10b). During 2023 the EU Emissions Trading System (ETS) achieved net CO₂ reductions of about 25 million tonnes (Mt) through the purchase of allowances by operators. In combination, the EU ETS, the CH ETS and the ICAO Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA) could yield an average 39 Mt net CO₂ reduction per year over the period 2024-2026 (see Market Based Measures chapter for details).

Meeting the ReFuelEU Aviation 

 supply mandate for Sustainable Aviation Fuels (SAF) would cut net CO₂ emissions by at least 65 Mt (47%) in 2050 under the base traffic scenario. This is lower than the estimated 60.8% emissions reduction in the European Commission Impact Assessment for ReFuelEU Aviation due to more conservative assumptions  . The emission reductions in  are based on the final ReFuelEU Aviation minimum level of SAF supply and emissions reductions in line with the mandate and sustainability criteria (see Appendix C for more details on the SAF scenario). Under ReFuelEU Aviation, EASA will collect data from aircraft operators and aviation fuel suppliers on SAF, including their sustainability characteristics. The actual reported values of SAF uptake and the CO₂eq emissions reductions for each SAF category will be used to inform the net CO₂ estimates in future versions of this report.

Electric and hydrogen aircraft were assumed to deliver an additional 5% net CO₂ reduction by 2050 and may have a larger emission reduction potential beyond this date.

The 41^st ICAO Assembly in October 2022 adopted a global Long-Term Aspirational Goal (LTAG) for international aviation of net-zero carbon emissions by 2050 in support of the Paris Agreement’s temperature goal 

. The LTAG does not attribute specific obligations or commitments in the form of emissions reduction goals to individual States. Instead, it recognizes that each State’s special circumstances and respective capabilities will inform the ability of each State to contribute to the LTAG within its own national timeframe. Each State will contribute to achieving the goal in a socially, economically and environmentally sustainable manner and in accordance with its national circumstances, and ICAO will regularly monitor progress on the implementation of all elements of the basket of measures towards the achievement of the LTAG .

Compared to the previous report, a slightly more conservative future engine technology scenario was used to predict emissions of nitrogen oxides (NO_X) out to 2050. The updated emissions trends chart (

) confirms that mitigating the growth in NOX emissions over the next decades remains a challenge. The same conclusion applies to a lesser extent to volatile particulate matter (PM) emissions ( ). Emissions of carbon monoxide (CO), unburnt hydrocarbons (HC) and non-volatile PM are expected to stabilise or even reduce by 2050 through the effect of fleet renewal and ATM improvements.

See Chapter 2 on Environmental Impacts for further information on the impacts of air pollutants, including ultrafine particles from aircraft, which is an emerging pollutant of concern that will be monitored under the revised EU Ambient Air Quality Directive.

In 2022, flights departing from EU27+EFTA represented 12% of total transport greenhouse gas (GHG) emissions and 4% of total GHG emissions in EU27+EFTA. Aviation GHG emissions of 2022 have already almost reached the pre COVID pandemic levels and increased by 84% compared to 1990. Overall, aviation was the third largest source of GHG emissions in the transport sector after road and waterborne transport 

. This increase is mostly due to traffic growth outpacing energy efficiency improvements and reductions of emissions from other sectors  .

NOX emissions from aviation have more than doubled since 1990 in EU27+EFTA, reaching a share of 14% in overall NO_X transport emissions of EU27+EFTA in 2022, which is similar to the pre-COVID share and represents an increase of 11% compared to 1990. This increase is mostly due to the growth in air traffic not being offset by the incremental improvements in engine technology to mitigate NO_X emissions, which is more technically complex compared to other modes of transport. In 2022, aviation was responsible for 4% of all PM2.5 emissions from transport in EU27+EFTA, with absolute emissions increasing by 35% since 1990. Similar to NO_X emissions, the overall share of PM2.5 is essentially back to pre-COVID levels. Black carbon, sulphur oxides and ammonia are among the other pollutants for which emissions from aviation have also increased since 1990 

.

 Despite the ongoing decarbonisation efforts, and the development of low carbon emissions aircraft (e.g. electric or hydrogen), air pollution from the sector will remain a challenge in the future.

 

Passengers need to be able to trust the information from aircraft operators regarding the environmental performance of their flights to make informed choices when comparing different options. The current lack of a common methodology, criteria and indicators with adequately reported, certified and monitored results does not facilitate this. As such, in order for consumers to be able to make an informed choice, more robust, reliable, independent and harmonised information is needed on the environmental impact of flights.

Pursuant to Article 14(11) of the ReFuelEU Aviation Regulation 

, the European Commission prepared an Implementing Act to be adopted by the end of 2024 setting out a standardised and science-based methodology to be applied for the estimation of flight emissions. The rules and conditions laid down in the proposal will incentivise competition between aircraft operators to reduce their emissions by improving the legal certainty of their environmental claims in relation to aviation fuels they purchase and use in their flights.

Airlines who volunteer to participate in the Flight Emissions Label will have to report operational data to EASA who will estimate emissions of future flights. In return, airlines will receive an approved label based on two metrics (kgCO₂eq per passenger and kgCO₂eq per passenger-kilometre). EASA is also tasked with setting up a website to provide passengers with detailed information on the flight emissions label, such as the methodology, assumptions and emissions estimations.

In April 2024, the European Commission and the EU Consumer Protection Cooperation Network initiated an investigation against 20 airlines with respect to potentially misleading green claims 

. This followed a similar finding in a Dutch court that environmental claims made by an airline were misleading and were in breach of consumer protection laws  . These types of claims are not confined to the aviation sector, and the European Commission is proposing a new Directive on Green Claims to increase confidence in the environmental information provided by companies on their product and services  . This type of policy measure to increase transparency recorded the highest levels of public support in a recent survey  .