Air travelers are typically told that turbulence is nothing to worry about, but as Singapore Flight SQ321 demonstrated on Tuesday, it can be fatal.
A 73-year-old Briton, Geoff Kitchen, died of a suspected heart attack, while several other people suffered serious injuries aboard the plane, which encountered severe turbulence at about 37,000 feet.
Passengers somersaulted, fainted, and left the cabin in “pools of blood,” which suddenly sank about 6,000 feet in a matter of minutes.
Now, scientists say climate change is worsening turbulence for planes, resulting in more sudden and violent movements and increasing the risk of fatalities.
Speaking to MailOnline, Isabel Smith, a turbulence researcher at the University of Reading’s meteorology department, warned that global warming causes jet streams (the narrow currents of fast-moving air that planes fly in to increase speed) are more “chaotic”.
Airport officials stand near the Singapore Airlines plane for flight SQ321 parked on the tarmac after an emergency landing at Suvarnabhumi International Airport in Bangkok, Thailand, May 22, 2024.
“The amount of turbulence is closely related to the speed of jet streams, fast-flowing bands of wind that spread around the world,” he told MailOnline.
“As the speed of the jet increases, the instability of the jet increases and the airflow becomes more chaotic, causing more turbulence.”
A particular type of turbulence called clear-air turbulence (CAT) is believed to have affected SQ321.
CAT is difficult to observe ahead of an aircraft’s path using remote sensing methods and is challenging for aviation meteorologists to forecast before it occurs.
“Clear air turbulence (CAT) is generated due to wind shear and therefore has a strong link with jet streams,” Dr Smith told MailOnline.
«Global warming refers to the rapid warming of the lowest layer of the atmosphere, where we live, called the troposphere.
‘There are several layers within the atmosphere and the layer above the troposphere is the stratosphere.
«The increase in greenhouse gases traps heat in the troposphere, which would normally be emitted to the stratosphere.
The troposphere is where humans live and climate exists; the lowest layer extends to approximately six miles
«This creates a strong temperature difference vertically in the atmosphere.
‘A stronger vertical temperature gradient will cause a more intense and chaotic jet stream.
“As the jet streams become stronger, it becomes more chaotic and unstable, and the number of CAT encounters increases.”
The CAT is often described as “invisible” because there are no visual clues, such as clouds, that can help experts predict dangerous areas.
“The main problem (with CAT) is that you can’t see it,” said Ramalingam Saravanan, a professor in the Department of Atmospheric Sciences at Texas A&M University who was not involved in the study.
“I think the best way pilots know is when another pilot has passed through it and radios their location.
“You can try to predict it statistically, but you can’t predict it by individual case because it’s a random process and the air seems clear and harmless, hence the name.”
Researchers at the University of Reading published an article last year revealed that severe turbulence has increased 55 percent in four decades.
Analyzing global CAT trends between 1979 and 2020, experts found “clear evidence” of large increases in CAT affecting aircraft at cruising altitudes.
In particular, they found that the largest increases in CAT occurred in the US and the North Atlantic, both regions with heavy air traffic.
Researchers at the University of Reading found that severe turbulence has increased percentage wise over four decades. Shown, average annual probabilities of encountering moderate or greater clear air turbulence (CAT) in (a) the year 1979 and (b) the year 2020 (darker areas in red indicate a higher probability)
Passengers cartwheeled, fainted and left the cabin in “pools of blood” as they were buffeted by turbulence. In the photo, bloodied personnel on board SQ321.
A 73-year-old Briton, Geoff Kitchen, died of a suspected heart attack and several other people suffered serious injuries aboard the plane, which encountered severe turbulence at about 37,000 feet.
At a typical point over the North Atlantic, the total annual duration of severe turbulence increased by 55 percent, from 17.7 hours in 1979 to 27.4 hours in 2020, the research found.
Moderate turbulence increased 37 percent, from 70.0 to 96.1 hours, and light turbulence increased 17 percent, from 466.5 to 546.8 hours.
While the US and North Atlantic have seen the largest increases, experts found that other busy air routes over Europe, the Middle East and the South Atlantic also experienced significant increases in turbulence.
Interestingly, there has been a greater increase in CAT in the Northern Hemisphere than in the Southern Hemisphere, which “deserves further investigation.”
According to the team, their study “represents the best evidence yet” that clear air turbulence has increased in recent decades, consistent with increasing global warming.
Meanwhile, a study 2017 estimated that climate change will significantly increase the amount of severe turbulence around the world sometime between the years 2050 and 2080.