Reckless expansion plans blow past European airports carbon limits

Planned expansions at twenty of Europe’s largest airports are incompatible with national climate targets and global warming limits. According to new research by T&E, the planned increases in air traffic across ten European countries will result in each airport exceeding its fair-share 1.7°C carbon budget by two to three times. On current growth plans, European aviation will exhaust its remaining 1.5°C carbon budget this year, and its 1.7°C budget by 2033.

Major airport expansions are underway, or have been announced, in large European cities including London, Paris, Madrid, Lisbon, Dublin, Frankfurt and Brussels. Airlines and airports tell governments that they can expand and fly more passengers, while still meeting Europe’s climate targets, on the promise that cleaner fuel and more efficient aircraft will cut enough emissions. However, the T&E analysis shows that every airport will exceed its carbon budget, even when accounting for Sustainable Aviation Fuel (SAF) uptake and more efficient aircraft.

“Increasing traffic volume by adding runways and extending terminals cancels out any benefits from cleaner fuels or efficient engines. No plausible tech improvement can close the gap in time,” said Denise Auclair, head of T&E’s Travel Smart campaign. “After this summer’s dramatic heat, fires and drought, governments have a stark choice: they can either make it worse by approving climate-busting expansion, or show decisive action and stop it now.”

The largest budget overshoots in the current airport expansion plans are in Lisbon and Porto (Portugal), at 2.8 times the budget, followed by Dublin (Ireland) at 2.6 times. Lisbon and Porto airports, which together represent around 80% of Portuguese aviation emissions, would need to cut emissions by 12% every year from now on instead of expanding, if they are to remain within national climate limits. Of the ten countries analysed, Portugal has the largest airport emissions increase compared to its economy: an extra 18 million tonnes of CO₂ from the planned new Lisbon airport is equivalent to half a year of emissions from Portugal’s entire economy.

In the UK, the extra emissions from a third runway at London Heathrow between 2035 and 2050 would equal a full year of emissions from Croatia's entire economy.

Aviation emissions in Spain are growing faster than in any other major European country. Nevertheless, the country is seeking to expand 12 of its busiest airports simultaneously, including Madrid, Barcelona, Palma and Málaga. These four airports accounted for two thirds (66%) of Spain's departing emissions in 2025. Their expansion will add 35 Mt of CO₂, which is equivalent to Portugal’s annual emissions. Madrid’s expansion alone will add 23 Mt of CO₂ emissions over 25 years, exceeding the total Spanish aviation emissions in 2025.