What is clear air turbulence?

In a clear sky, planes can be struck by severe turbulence and it’s likely to occur more often due to climate change.

Transcript

00:00 A recent rise in severe turbulence incidents has a troubling connection to climate change.

00:07 So what causes this scary phenomenon, especially when there aren't even any clouds around?

00:13 A dozen people have been injured by severe air turbulence with Australians among those on board.

00:18 A Singapore Airlines flight that plummeted 6,000 feet in five seconds are being treated in hospital.

00:24 The tarmac quickly became a makeshift emergency room.

00:28 The turbulence on this Singapore Airlines flight killed one person and left dozens hospitalised,

00:36 including 22 with spinal injuries.

00:40 And this Qatar Airways flight left eight people hospitalised.

00:47 One was struck by something called clear air turbulence, or CAT for short.

00:56 Unlike regular turbulence, CAT can't be seen on satellites or on board sensors,

01:02 and strikes unexpectedly in clear skies.

01:06 Clear air turbulence, there's no way of knowing when it's going to happen,

01:10 where, and the severity or intensity of the turbulence.

01:15 Research has found that CAT has increased and will continue to increase due to climate change.

01:21 As our planet warms, the temperature difference between air masses gets bigger.

01:26 This disrupts the jet stream, a high-altitude wind current,

01:30 making it more unstable and creating more opportunities for CAT to form.

01:36 Clear air turbulence increased by 55% over the North Atlantic from 1979 to 2020,

01:45 according to research from the University of Reading in England.

01:49 Certainly projecting a doubling or a trebling in the amount of turbulence in a few decades' time,

01:55 but that will just mean that we go from 0.1% of the atmosphere having severe turbulence in it

02:00 to 0.2 or 0.3%, and that's certainly not going to mean we're going to have to shut down

02:05 parts of airspace and say there's too much turbulence. I don't think that's on the cards, really.

02:10 (ethereal music)

02:12 [MUSIC]