After a calamitous few years for the aviation industry 2024 looks set to be a boom year for international air travel, with estimates that 9.4 billion passengers will take to the skies, breaking all previous records. Dublin airport is witnessing a resurgence of passenger numbers, and the Dublin Airport Authority (DAA) has just lodged a 7,000 page planning application to increase capacity from 32 million to 40 million passengers per year. The application was described by Fingal County Council as one of “significant scale and complexity”. It includes a proposal to expand the north and south aprons of the airport.
Local residents and other interested parties will be able to make submissions in relation to the proposal before January 29th. In justifying this increase the airport authority will have to demonstrate that more passengers and flights can be accommodated in a way that is consistent with Ireland’s climate legislation and policies. On top of the localised noise, traffic and air pollution impacts, airports are significant drivers of aviation-related greenhouse gas emissions. Aircraft engines burn fossil fuels, releasing CO2 and other pollutants into the atmosphere. Contrails (condensation trails) and cirrus clouds formed by aircraft at high altitudes also trap heat in the atmosphere, contributing to a warming impact.
While air travel contributes just 2.7 per cent of global greenhouse gas emissions, this is expected to increase as demand continues to grow. Projections for Europe alone suggest a growth in demand anywhere between 19 per cent and 76 per cent by 2050, by which time the world is supposed to have reached net zero carbon-dioxide emissions.
To be consistent with the legally-binding obligation in the Paris Agreement of limiting warming to “well-below 2 degrees C above pre-industrial levels”, emissions from the aviation sector, like all other sectors, will need to be reduced to near-zero. To avoid any increase in CO2 from aviation growth would need to be offset by fuel-efficiency gains or the use of alternative fossil-free fuels.
The latest Intergovernmental Panel on Climate Change (IPCC) assessment report from 2022 noted that sustainable biofuels, low-emissions hydrogen, and derivatives (including synthetic fuels) will be essential for the industry to decarbonise, but these require production process improvements and cost reductions that have not yet materialised. The IPCC also noted that a reduction in long-haul aviation is the single most important demand-side mitigation measure for the sector.
However the aviation industry has been adept at resisting efforts to curb demand growth. The Open Skies framework guiding the sector since the 1940s means that the aviation sector is highly globalised, mobile and fiercely competitive. This leave-us-alone mindset even applies to emissions reporting.
Take Dublin airport’s Carbon Reduction Strategy for example. A whopping 66 per cent of the airport’s reported emissions won’t be included in the DAA’s climate target at all. Those emissions come from the taking off and landing of the airplanes. To most people airplanes taking off and landing is the core business of an airport. But thanks to carbon accounting protocols and the special status of international transport in climate policy, these emissions are considered Scope 3 and therefore outside of the direct control of the DAA. And those Scope 3 emissions don’t include the emissions from the aircraft once it’s in the air. The DAA says while not directly responsible for these emissions it is “committed to working closely with our business partners to help them reduce” them.
Since airlines are unlikely to do anything that upsets their business models, it is only by managing airport capacity that governments can limit the environmental and climate impacts of aviation. Under ideal circumstances, as the Taoiseach acknowledged recently, government intervention would distribute Dublin’s excess air traffic to Cork and Shannon. However even governments cannot make airlines go anywhere that they don’t want to go.
A roadmap to sustainable aviation starts with not making the problem worse: we need to act urgently to prevent a rapid increase in aviation emissions. The EU should be pulling out all the stops to introduce taxes on aviation fuels and incentivise the development and deployment of sustainable aviation fuels, including hydrogen. We could begin by taking a critical look at Dublin airport’s expansion plans, restricting private jets and insisting on a reduction in corporate travel to 50 per cent of pre-Covid levels.
With traditional jet engines set to continue to be in operation for decades to come, we need policies to mandate the deployment of sustainable aviation fuels (SAFs). Most importantly, the industry has to understand that its future survival depends on whether it can scale up these new technologies rapidly, and contain the growth in demand. In that context maintaining a lower cap on passenger numbers at Dublin airport makes sense.
Sadhbh O’Neill is the senior climate adviser to Friends of the Earth Ireland