READING, England, Wednesday May 10, 2017 – At least 27 passengers were injured when an Aeroflot flight from Moscow to Bangkok hit severe turbulence earlier this month. But according to scientists, this may soon not rank as an isolated incident, with climate change expected to increase this type of activity by as much as 149 percent.
A growing amount of research shows that as the planet warms from climate change, the second half of this century will see an increase in turbulence, especially along the heavily-travelled transatlantic routes in the Northern Hemisphere.
According to Dr Paul Williams of Britain’s University of Reading: “Climate change is strengthening the north-south temperature difference that drives the jet stream. A stronger jet stream is less stable and means more clear-air turbulence.”
Clear-air turbulence is the most common cause of an in-flight rodeo ride, and can result in significant injuries, such as those experienced on the recent Aeroflot flight.
Williams and his colleagues’ latest research, published in the journal Advances in Atmospheric Sciences, showed that turbulence of all severities increases in model simulations of a warming climate, but the largest increase is seen in “severe turbulence” – the kind that hit the Russian carrier.
According to Williams: “Increases in light and moderate turbulence will not injure anyone, but they will cause anxiety amongst nervous fliers.
“On the other hand, the 149 percent increase in severe turbulence that we have calculated does have the potential to cause more serious injuries.”
Clear-air turbulence (CAT) is caused by rapid changes in speed or direction of air movement, and occurs most commonly in and around an invisible current of rapidly moving air called the jet stream. This is found at a height similar to where commercial planes fly, around 30,000-40,000 feet.
The jet stream generally follows the boundary between hot and cold air, and is strongest when the difference between the hot and cool sides is the strongest, which occurs during the winter months.
The theory behind the climate change and turbulence link is simply that if climate change influences the intensity and position of the jet stream, the turbulence resulting from that jet stream would be impacted.
According to Williams, there’s even evidence that the rate of turbulence injuries has risen significantly since the 1980s, even after adjusting the statistics to account for the growth in aviation. He nevertheless stopped short of saying that it was caused by the warming already experienced.