Flying a plane through windy, stormy conditions can cause a dangerous, turbulent ride. But a clear blue sky does not guarantee smooth cruising.

Williams: “Clear air turbulence is completely invisible, as its name suggests, so it’s nothing to do with flying through a storm. … It comes out of the blue, often without warning.”

And Paul Williams, a professor of atmospheric science at the University of Reading in the UK, says it’s getting more common.

He explains that clear air turbulence is caused by instability in the jet stream, which is increasing as the atmosphere warms.

In a recent study, his team found that over the past 40 years, severe clear air turbulence over the North Atlantic increased by more than 50%.

Scientists expect that this type of turbulence will grow even more common as global warming continues.

Williams says people who fly do not need to be scared, but they should take precautions to stay safe.

Williams: “It’s really, really, really rare for someone seat-belted to be injured in a turbulence encounter. It almost never happens.”

So whether the seat belt sign is on or off, Williams recommends that travelers buckle up as flying gets bumpier in a warming world.

Reporting credit: Sarah Kennedy / ChavoBart Digital Media