Dozens of people were injured, some seriously, during a bout of severe turbulence on an Air Europa flight traveling from Spain to Uruguay at the beginning of July. Just a few weeks earlier, at the end of May, one man died (of a suspected heart attack) and tens of others were injured amid “sudden extreme turbulence” during a Singapore Airlines flight en route to Singapore from London. In both instances, the flights made early, emergency landings.
Extreme turbulence is rare. However these two recent incidents have stoked concern and fear among fliers that dangerously rough flights are becoming more common. Scientific studies do indicate that climate change is increasing the occurrence and intensity of airplane turbulence. Atmospheric shifts triggered by global warming are set to cause trouble for the airline industry, making flights longer and costlier–but experts suggest passengers need not be too worried. Basic precautions can help you stay safe.
What is turbulence?
Turbulence is irregular air movement, experienced by plane passengers as bumps and shaking. There are three basic causes of severe in-flight turbulence: terrain, thunderstorms, and air currents, says Shem Malmquist, an aeronautics instructor at the Florida Institute of Technology and a B-777 pilot. Geologic formations like mountain ranges disrupt airflow and can bring on bumps, in a process known as “mountain wave turbulence.” Thunderstorms can churn up the atmosphere and trigger “convective” turbulence in their immediate vicinity and also “near-cloud” turbulence up to tens of miles away, says Isabel Smith, a meteorologist and PhD student at the University of Reading in England. Finally, jet streams–narrow bands of fast wind that circle the globe at high atmospheric elevations–can become swirling and chaotic under the right conditions.
Why is turbulence becoming more common?
Some research indicates that all three drivers of turbulence could be exacerbated by climate change. Global warming isn’t making mountains bigger, but it is leading to upper-atmosphere shifts that may promote more intense air movement above mountains, according to one 2023 study published in the journal Climate and Atmospheric Science. That same study also found evidence that near-cloud turbulence, spurred by storms, is set to worsen with warming as well. Though more work is needed to confirm these findings, Smith tells Popular Science. “There’s only one published paper that’s really looked at it,” she says.
Previous research has concluded that storms are generally becoming more intense and frequent due to climate change, in part because warmer air holds more moisture. As a result, Smith says she’d expect convective turbulence to become more common and extreme as well.
But the vast majority of studies of turbulence and climate change have focused on the clear-air (i.e. cloudless) turbulence associated with jet streams. And here, science going back more than a decade has repeatedly shown we’re in for a rough ride.
In a study led by Smith and published last year, she concluded that every one degree Celsius of increased warming is set to boost jetstream-related turbulence by 9%-14%, depending on the season, through 2050. Another 2023 paper from the same lab group assessed weather reanalysis data and found that the most severe type of this sort of clear air turbulence has already increased by 55% from 1979 to 2020.
Greenhouse gas emissions make Earth’s lower atmosphere much warmer because they keep heat trapped in the bottom layers. Since less heat is escaping the lower atmosphere, the upper atmosphere is actually becoming colder, as our planet’s surface warms. The result is a rapid divergence between upper and lower atmospheric temperatures.
Jet streams exist because of thermal gradients–sometimes between low-elevation air in the Arctic and equatorial regions, and sometimes between higher and lower elevation air. As polar air gets warmer and higher elevation air gets colder, these shifts are speeding parts of the stream up and slowing others down, inducing chaos in the global air currents, explains Smith. “There are lots of shifts and temperature changes in the atmosphere, which are leading to the jetstream itself changing. When the jet isn’t in a set position, it can produce more favorable conditions for turbulence,” she says. “You have really fast bands of wind, then slower bands of wind on the edge. It results in these swirls and curls that break down into turbulence.”
What can airlines do about it?
Avoiding summer flights won’t solve the problem. Despite the link to warming, winter is actually generally considered the worst time for trans-Atlantic, northern hemisphere flights. Climate change is expected to intensify turbulence in all seasons.
The good news is that most bouts of turbulence show up in forecasting, which is about 75%-80% accurate, notes Smith. Weather radar reveals turbulence associated with storms. Terrain is unmoving and a predictable influence on atmospheric conditions. And meteorologists monitor the jetstream, revealing information about most clear-air turbulence, says Malmquist. “The scientists are pretty good at mapping where the jetstream is and then also if the jetstream is curling and bending around, which is a good indication of turbulence for [pilots],” he notes.
However, atmospheric conditions can change quickly. With a storm, that’s visible to a pilot. With clear air turbulence, it’s not, says Smith. “It can hit the aircraft quite suddenly, without any warning.” And, even in cases where clear air turbulence is clearly forecasted, pilots may not always be able to easily avoid it, especially on long-haul, cross-ocean flights.
“We’re relying on the jet stream to carry us across and not burn the fuel sometimes,” says Malmquist. On long distance flights, “descending out of the jet stream to avoid turbulence is going to be a big problem… when we don’t have that flexibility in routes and altitudes,” he adds.
Air traffic controllers and pilots “always put safety as a priority,” says Smith. So moving forward, a bigger part of flight planning will be jetstream conditions. Ultimately, it will likely mean re-mapping flight routes, longer flights to avoid turbulent areas, and burning more jetfuel, she says. “We’ll have more convoluted routes, which will also mean that we’re using more fuel and producing more emissions,” adding to the problem of jetstream destabilization in the first place.
How dangerous is turbulence during a flight?
Even with the rising risk of turbulence, airplanes remain the safest ways to travel. Trips by car, motorcycle, train, ferry, and bus are all significantly more likely to hurt or kill you.
Turbulence on a flight is unpleasant, and in rare, unfortunate cases dangerous. However, planes themselves are built to manage all manner of jostling. “The airplane can handle it,” says Malmquist–passengers should not worry that a plane will incur structural damage or fall apart.
Instead, the real threat is what can happen inside an airplane amid extreme turbulence. All that up and down movement can send objects and people bouncing. The best way to keep yourself safe is rather obvious and boring: wear your seatbelt.
“People need to keep their seatbelts fastened,” says Malmquist. Even if the cabin light is off and passengers are technically free to move about the plane, it’s always best to stay seated with your seatbelt secure for as much of a flight as possible, considering how rapidly turbulence can materialize. “It’s not a reason to avoid flying, but it’s a really good reminder that those seatbelts are important,” Malmquist emphasizes.
“If you need to pee, go quickly and get back and get buckled in,” agrees Smith. “You wouldn’t sit unsecured in a car going 100 miles an hour,” she says–so why risk it in a plane traveling many times faster?