Aeroplanes are experiencing more turbulence than they did in previous decades because of climate change, new research has shown.

Clear-air turbulence, which can appear unexpectedly and in extreme cases damage aircraft and injure passengers, has been found to have increased in various regions across the world.

In the North Atlantic – one of the world’s busiest routes – the total annual duration of severe turbulence increased by 55% from 17.7 hours in 1979 to 27.4 hours in 2020.

Moderate turbulence increased by 37% from 70.0 to 96.1 hours, and light turbulence increased by 17% from 466.5 to 546.8 hours.

Every additional minute spent travelling through turbulence increases wear and tear on the aircraft, as well as the risk of injuries to passengers and flight attendants

The researchers, from the University of Reading, said this was predicted to increase with climate change but that their study provides strong evidence it is happening already.

Warmer air from CO2 emissions is increasing wind shear in the jet streams – when the wind suddenly changes speed or direction in a small area.

Scientists said clear-air turbulence is already costing airlines hundreds of millions a year but more investment is needed to forecast and detect the invisible phenomenon.

Professor Paul Williams, an atmospheric scientist who co-authored the study, said: “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.

“We should be investing in improved turbulence forecasting and detection systems, to prevent the rougher air from translating into bumpier flights in the coming decades.”

PhD researcher Mark Prosser said: “Turbulence makes flights bumpy and can occasionally be dangerous.

“Airlines will need to start thinking about how they will manage the increased turbulence, as it costs the industry 150–500 million dollar (£121-483 million) annually in the USA alone.

“Every additional minute spent travelling through turbulence increases wear and tear on the aircraft, as well as the risk of injuries to passengers and flight attendants.”

The study, published in the journal Geophysical Research Letters, found that the US and the North Atlantic have seen the largest increase in turbulence, though it also rose significantly in busy flight routes across Europe, the Middle East and the South Atlantic.