It’s the holiday season in Europe, with thousands traveling across countries amid blistering heat. Taking a flight is usually the preferred option, which just makes sense as tickets are up to 30 times cheaper than taking a train, according to a new report. However, this is having a big toll on the climate due to flights’ high emissions.

Greenpeace compared the costs of flight and train tickets on over 100 routes in Europe at nine different points in time. The analysis showed train tickets are on average twice as expensive as flights. The most extreme difference was on the London-Barcelona route, in which taking a train costs 30 times more than a flight.

Flights are a significant source of greenhouse gases, primarily carbon dioxide (CO2), which contribute to global warming when released into the atmosphere. Aviation’s carbon footprint now accounts for about 2.5% of the world’s global emissions. However, this is expected to increase, with passenger numbers likely doubling by 2037.

According to the International Civil Aviation Organization (ICAO), an economy-class return flight from London to New York emits around 0.67 tons of CO2 per passenger. This is equivalent to 11% of the average annual emissions for a UK citizen during daily life, the BBC estimated. In comparison, all types of trains are more environmentally friendly.

“Airlines benefit from outrageous fiscal advantages. Planes pollute far more than trains, so why are people being encouraged to fly? Low-cost airlines, in particular, have exploited every loophole and trick in the book,” Greenpeace climate campaigner Lorelei Limousin said in a statement. “Politicians must act to turn this around.”

Flight’s climate problem

The countries with the most expensive train tickets compared to flights are the UK, Spain, Belgium, France and Italy, the report showed. Whereas in Central and Eastern Europe, trains are more often cheaper in relation to flights than in Western Europe, the train frequency, speed, and connections are worse than in Western countries.

Greenpeace also found that some of the most “effective” train routes, such as Amsterdam–London (four hours by train both ways) are still among the most popular short-haul flights in Europe. Low-cost companies are present all over Europe, the NGO said. They operate in almost 80% of the routes analyzed, using “unfair” pricing strategies.

“As one of the most important considerations when booking, especially given the cost-of-living crisis, the primary way to encourage more people to choose rail above air travel would be to ensure domestic train travel is more affordable than the alternative flight route option,” James Dunne, CEO of Rail Online, told The Independent.

Looking ahead, Greenpeace calls for European governments to make rail more affordable than air transport, for example introducing long-term and cross-border tickets. They suggested phasing out airline subsidies and using a fair taxation system based on CO2 emissions to make revenues available for cheaper train tickets.

Some countries are already taking action in this direction. France banned some short-haul domestic flights this year. Journeys that are possible in less than two-and-a-half hours by train can no longer be traveled by plane. Also, in 2020, Luxembourg became the first country in Europe to provide free public transportation to everyone.