Taking longer flights could help reduce the impact of climate change, EU report claims

MANY people are flying less in an effort to be eco-friendly, but an EU report has suggested a different way to help tackle climate change: fly for longer.

Up to two- thirds of the climate impact from aviation comes from noncarbon dioxide sources, the European Union Aviation Safety Agency said, much of which is caused by contrails created when planes fly through humid, cold parts of the atmosphere. The group suggested this impact could be reduced if planes took alternative routes, either by flying higher or lower in the sky or by flying a less direct path.

The calculations would be based on meteorological models, and limits could be set on the greatest acceptable increase in either flight time or distance flown. Currently, air traffic control is mainly concerned with preserving safety by keeping planes away from each other, so considering the impact on climate would mark a significant change in approach, the report said.

The option was one of six suggested to the European Commission, which was asked by the EU to investigate nonCO2 emissions from aircraft. Adding cleaner fuels to aeroplane fuel mixes and charging airlines for nitrogen dioxide emissions were also raised as potential solutions.

While it has long been known that contrails contribute to climate change, the extent of this impact is unclear.

Contrails form in the atmosphere at an altitude of between five and eight miles, when water vapour from the aeroplane exhaust freezes on to soot particles, creating wispy cirrus clouds. This contributes to global warming by trapping heat on Earth, but the effect lasts only a few hours. Scientists think that cutting out contrails would slow warming and buy the world time to make longer-term cuts to CO2 emissions.

More research is needed on how to predict accurately the areas where large contrails are most likely to be formed, the report added. To test the idea, a pilot scheme would need to take place in one specific area, such as over the Atlantic. If that was successful, the policy could come into force in five to eight years.

Jo Dardenne, the aviation manager at the European sustainable transport group Transport and Environment, said: “The EU should lead by ensuring air traffic doesn’t bounce back to preCovid levels while getting planes to fly smarter routes and use e-fuels from renewable sources.”