Private jets produce more contrails than previously thought
New study finds that private jets create similar contrails to much larger commercial aircraft with significant climate consequences
Recently, there has been much reporting about a new study finding that newer, fuel-efficient aircraft create more contrails than older aircraft. This is mainly because they fly at higher altitudes (which they don’t necessarily have to if we want to minimize the contrail warming from them).
Anyway, another finding in the same study led by researchers from Imperial College London, has received less attention from the media: Private jets produce more contrails than previously thought.
Business jets – a luxury reserved for the ultra-rich – usually fly at higher altitudes than commercial aircraft, where traffic is lighter and the air is thinner, which saves fuel.
Often, these jets fly at altitudes previously thought to be too high in the atmosphere to create lasting contrails. However, in the new study, researchers examined satellite imagery to identify contrails over the Eastern part of North America and the Western part of the North Atlantic. When linking these photos of contrails to the aircraft that created them, the researchers discovered something surprising: Despite being smaller and using less fuel, private jets create similar contrails to much larger commercial aircraft.
This is a problem because contrails have a warming effect on the climate when they spread out and become high-altitude cirrus clouds, which act like blankets on Earth and keep the planet warm.
Massive climate impact
The individual carbon footprint of a private passenger compared to most commercial passengers is already substantial (estimated at around ten times higher per passenger). However, if private jets carrying a handful of passengers can make warming contrails similar to those created by 500-passenger commercial jets, then the climate impact of that handful of private passengers could be massive.
Dr Edward Gryspeerdt, the study's lead author and a Royal Society University Research Fellow at the Grantham Institute – Climate Change and the Environment, said: “It's common knowledge that flying is not good for the climate. However, most people do not appreciate that contrails and jet fuel carbon emissions cause a double whammy warming of the climate. Despite their smaller size, private jets create contrails as often as much larger aircraft. We already know that these aircraft create a huge amount of carbon emissions per passenger, so the super-rich can fly in comfort.
Fewer traffic jams higher in the sky
However, there is a solution for private jets to avoid creating this unintentional contrail warming. If operators use software designed to predict the contrail-prone areas, their private jets can fly around those areas and stop unnecessarily heating the planet with contrails. And since the higher altitudes where business jets often fly are less congested, getting permission from air traffic control to change the flight plan should be even easier for private jets.
Go to Blue Lines’ educational website to explore contrails in depth.
(As regular readers of the Blue Lines newsletter will know, contrails are the wispy white stripes that airplanes sometimes leave behind in the sky (made from water vapor and engine soot). Some of these condensation trails can spread out and become high-altitude ice clouds (cirrus), which reflect some of the sun’s energy back into space but also trap outgoing energy in the atmosphere, resulting in a net heating of our planet equivalent to 1-2% of human-induced global warming. However, we can relatively easily avoid most warming contrails by flying around the contrail-prone areas in the atmosphere. This climate solution – often called contrail management or contrail avoidance – is what Blue Lines promotes and wants to see spread worldwide.)
See you soon.
Joachim Majholm,
Blue Lines