What to know about air turbulence before your next flight

Customers may need to brace themselves for increased air turbulence while flying as severe storms and stronger jet streams driven by climate change could make bumpy rides more frequent.   

A Singapore-bound flight was forced to divert Monday after hitting severe turbulence over the Andaman Sea, causing dozens of injuries and one death while in flight. The recent incident has sparked questions over whether more severe turbulence can be expected if jet streams grow stronger.  

Here is what to know about how climate change and severe weather could impact your flight. 

What is turbulence, and what causes it?

The Federal Aviation Administration (FAA) defines turbulence as “air movement created by atmospheric pressure, jet streams, air around mountains, cold or warm weather fronts or thunderstorms.”  

There is also “clear air turbulence,” which the National Weather Service describes as occurring at about 15,000 feet when there are no cumuliform clouds, a common type of clouds typically resembling cotton balls that includes both fair-weather varieties and thunderstorms. 

The National Weather Service identifies four kinds of turbulence: light, moderate, severe and extreme. Light and moderate turbulence can cause passengers to feel strained against their seat belts, and some unsecured objects may move around. Severe and extreme turbulence can cause passengers to be forced violently against their seatbelts.   

Larry Cornman, a project scientist at the National Center for Atmospheric Research, said turbulence is “the natural state of the atmosphere,” adding that people typically do not notice it because the planes they’re on are so large.  

“Now, there are certain conditions under which there is enough motion and energy in the atmosphere to move an aircraft around or in case like we saw the other day, move it quite a bit,” he said in an interview.  

What caused the turbulence on the Singapore Airlines flight?

It’s still not clear what kind of turbulence may have impacted the Singapore Airlines flight as officials begin to investigate the incident.   

Jonathan Porter, a senior vice president and chief meteorologist at AccuWeather, said his initial analysis into the flight suggests an “explosive” thunderstorm could have brought on the severe turbulence. 

“We did review high resolution satellite imagery. And the thunderstorms that were developing in this area were notably intensifying very quickly, and it does look like one of those situations where there could be these updrafts that are occurring and very little awareness of just how fast it’s developing,” he said in an interview.   

“It shows once again, how dangerous thunderstorms can be for aviation,” he added.  

He said that while the plane was flying at an altitude of about 37,000 feet, a thunderstorm appeared to be developing quickly below it. Because the aircraft was flying at such a high altitude, the pilots were likely unable to detect the storm using their on-board radar, he said.  

Porter said the thunderstorm could cause an updraft of air in the atmosphere that can cause turbulence.  

“And that air sometimes is rapidly rising at more than 100 miles per hour in that updraft, and so that gives the pilot very little time, very little to no time to react. And it can result in these sudden turbulence issues,” he said.  

Cornman said the incident took place in seconds, describing it as a “very narrow event.”  

“You put all that energy in a very short, small piece of space and time, that energy is going somewhere and it’s going into the wind, and it moves the aircraft dramatically,” he said.  

Does climate change affect turbulence?

Some research has shown clear-air turbulence may be on the rise due to climate change.   

Research from the University of Reading last year found that severe in-air turbulence increased 55 percent between 1979 and 2020. The increase in turbulence is “consistent with the effects of climate change,” the researchers found.  

“Following a decade of research showing that climate change will increase clear-air turbulence in the future, we now have evidence suggesting that the increase has already begun,” said Paul Williams, the co-author of the study, at the time.   

Porter said the clear-air turbulence is caused by jet stream winds, which “can be flowing faster, as the atmosphere warms.”   

Jet streams are bands of strong winds in the upper atmosphere. Some research suggests that they are strengthening as the climate changes, which can make flights faster, but also subject to more potential turbulence.  

“There’s more of a temperature gradient established in the atmosphere. And that can result in greater jet stream winds which can lead to greater incidence of clear air turbulence,” Porter added.  

How can turbulence be predicted?

Jennifer Stroozas, the warning coordination meteorologist at the National Weather Service’s Aviation Weather Center, said the center focuses on making weather forecasts of the entire atmosphere that pilots can use to navigate around severe weather and turbulence. 

“So if we know the jet stream is sitting at a certain altitude in the sky, we’ll give that specific information in either a forecast or an advisory or a warning because sometimes that’s useful information of where they can find a smoother ride,” she said in an interview.   

The Aviation Weather Center provides warnings and forecasts for potential hazardous weather for aircraft. Stroozas noted that measuring turbulence can be a “little bit subjective” because larger airplanes are affected differently than smaller airplanes.   

She said the center relies on pilot reports, as well as modeling of the atmosphere and the conditions, to measure turbulence. She also noted that the center keeps an eye on thunderstorms and other potential weather hazards that can impact aviation.   

How can you stay safe on flights?

Deaths and severe injuries from turbulence on flights remain rare. The FAA reported 163 total turbulence-related severe injuries between 2009 and 2022, according to its data.  

The FAA urges everyone to keep their seat belts fastened while in-flight to prevent turbulence-related injuries. The Association of Flight Attendants also issued a statement following the Singapore Airlines incident to urge passengers to heed instructions of the crew.   

“As our climate changes, severe and clear air turbulence instances are on the rise. Always follow crew instructions and wear your seatbelt whenever seated. It is a matter of life and death,” the organization said.