Climate change could make long flights even longer and cost airlines an estimated $22 million more per year in fuel — costs that will likely be passed on to passengers.
A study published last month in the journal Environmental Research Letters finds that a warming climate may strengthen jet stream winds, increasing headwinds on westbound transatlantic flights. Those same wind changes act as tailwinds for eastbound trips, potentially shortening flights from the United States to Europe by roughly 15 percent in some cases.
The jet stream is driven by temperature contrasts between tropical and polar air at high altitudes. As those temperature patterns shift with global warming, the jet stream’s strength and position can change, altering flight conditions for aircraft that routinely cross those high-altitude wind patterns.
On an individual flight the average effect is modest: researchers estimate an added round-trip time of about one minute and 18 seconds. But when accumulated across the entire transatlantic network, the impact becomes significant. The study’s author, Dr. Paul Williams, an atmospheric scientist at the University of Reading, told the BBC that the aggregated effect amounts to about 2,000 additional hours of flight time per year.
That extra time in the air translates into higher fuel consumption and greater emissions. According to the study, the increased headwinds could cost airlines roughly $22 million in extra fuel annually and produce an additional 70 million kilograms of CO2. Those costs and emissions exacerbate the aviation sector’s environmental footprint at the same time the industry faces growing pressure to reduce it.
“There is a robust increase in the round-trip journey time, which means planes spending longer in the air,” Dr. Williams said. “When you add that up for all transatlantic aircraft you get an extra 2,000 hours of planes in the air every year, with $22 million extra in fuel costs and 70 million kg of CO2. The aviation industry is facing pressure to reduce its environmental impacts, but this study shows a new way in which aviation is itself susceptible to the effects of climate change. This effect will increase the fuel costs to airlines, potentially raising ticket prices, and it will worsen the environmental impacts of aviation.”
While eastbound flights may benefit from stronger tailwinds, the net effect across the network is an increase in fuel use and emissions as airlines contend with changing wind patterns. Even small average delays per flight add up across thousands of transatlantic journeys, influencing operational costs, scheduling and environmental performance.
As climate-driven changes to the jet stream continue, airlines and regulators may need to consider these evolving conditions in fuel planning, route optimization and broader strategies to reduce aviation’s carbon footprint.