This Small Change Could Cut Aviation's Carbon Footprint by 35 Percent

The studies found that between two and 10 percent of flights account for the vast majority of contrails. That’s because these trails of condensation occur primarily in humid and icy parts of the atmosphere. By rerouting flights that pass through these areas, much of that “heat blanket” could be avoided.

In 2023, the New York Times reported on data showing that in many cases, pilots could be directed to fly over or under parts of the atmosphere where they’re most likely to produce contrails. What’s more, doing so wouldn’t cost airlines much money. Airlines could feasibly reduce 73 percent of contrails with just a 0.11 percent increas, according to reporting in MIT Technology Review.

Why the added fuel burn could be worth it

Burning more fuel releases more emissions, but the paper’s coauthor Marc Shapiro told MIT Technology Review, “ . . . what we’re showing in this paper is that the added fuel burn is a lot less than we expected.”

This is a point that deserves more attention. Jet fuel is nearly as flammable as diesel and is the primary source of carbon emissions in both commercial and non-commercial aviation. However, due to the small amount of extra fuel that would need to be burned to avoid creating contrails — far less than what is burned during take-off and landing of the flight, in most cases — the climate impact of this could be huge. This is especially true at scale, and played out over a multitude of years.

Even though electric airplanes and more efficient airplane design builds are under development, decarbonization of commercial flights is decades away, if it’s even possible at all. Unless humanity is going to stop flying entirely, small steps like reducing contrails will prove to be pivotal moments in making this high-impact industry slightly more sustainable.

Making a small portion of flights even a little cleaner could have a massive impact on the overall climate impact of aviation, which accounts for about four percent of humanity’s total carbon emissions and is among the most challenging industries to decarbonize.