New study suggests a simple, cost-effective approach to limit contrails’ warming effect
Jet contrails, the vapor trails left behind by airplanes, are known to contribute significantly to climate warming, but a new study claims this issue could be largely mitigated with a few adjustments costing just a few pounds per flight.
Contrails’ real climate impact emerges, sparking discussion at COP29
Contrails form when planes pass through cold, humid air, causing engine vapors to condense. These trails, sometimes mistaken for “chemtrails” in conspiracy theories, create artificial cloud layers that trap Earth’s heat. Experts say that this climate-warming effect nearly doubles the impact of aviation emissions from fossil fuels.
This issue will be addressed at the upcoming United Nations COP29 climate conference in Baku, marking the first time contrails are on the agenda for international climate talks.
Solutions as simple as changing flight paths
A recent study by Transport & Environment suggests that adjusting flight paths could substantially reduce the warming effect of contrails. “Just 3% of flights are responsible for around 80% of contrail-related warming,” said Carlos Lopez de la Osa of Transport & Environment, the advocacy group leading the study. “By tweaking the routes of certain flights, we could cut contrail warming by more than half by 2040, for under £4 per flight.”
Contrail formation is strongly influenced by geography, time of day, and season, with flights over North America, Europe, and the North Atlantic accounting for most contrail warming. Evening and winter flights produce the most warming contrails.
“Planes are already avoiding thunderstorms and turbulence zones,” Lopez de la Osa added. “We would just need to consider avoiding areas prone to contrail formation as another constraint.”
Combatting contrail misconceptions for climate progress
Contrails are often confused with “chemtrails” by conspiracy theorists who suggest these trials contain harmful chemicals intended for mind control, population management, or biological warfare. “Unfortunately, these conspiracy theories cloud a critical issue needing consensus,” said Matteo Mirolo of Breakthrough Energy, a COP29 discussion organizer.
To date, research into sustainable aviation fuels has been prioritized. However, experts believe that addressing contrails could yield substantial climate benefits at a much lower cost, providing a potential climate “win” as world leaders focus on innovative solutions at COP29.