Corrected: Research Cited At Conference Warns Of Increases In Turbulence


Evidence indicates that global warming is stimulating wind shear events at the jet stream level, with a significant increase in turbulence when transitioning in and out of the high-speed airflow at altitude. Speaking at the Sustainable Aviation Futures Congress in Amsterdam last week, Paul Williams, professor of Atmospheric Science at the University of Reading, U.K., said, “We have a lot of evidence that the jet stream is now 15 percent more strongly sheared since satellites began measuring it in the 1970s. And this is what causes a lot of turbulence, especially clear air turbulence [CAT]. That’s a massive shift. Our calculations indicate there is going to be twice or three times as much severe turbulence in the next few decades because of climate change.”

According to the U.S. National Transportation Safety Board (NTSB), there has been an increase in “head-slamming” turbulence on airline flights. Turbulence-related injuries have become the most common type of airline accident, said the NTSB, with cabin crew members 24 times more likely to be injured than passengers. Turbulence also accounts for more than $500 million yearly in damages and delays, said the board.

And while the strong tailwinds can speed up a journey from west to east, the opposite occurs when headed the other way. And since flights spend much more flight time flying at the slower groundspeed into the wind, the net result is longer flight times, overall, and increased fuel burn, according to studies cited at the Amsterdam meeting.

Mark Phelps
Mark Phelps is a senior editor at AVweb. He is an instrument rated private pilot and former owner of a Grumman American AA1B and a V-tail Bonanza.

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  1. My calculations indicate if it wasn’t CAT, it would have been something else increasing twice or three times due to global warming, also with effects measured in currrency. Maybe in Bitcoin. Wait! Did I say global warming? Sorry. Climate change.

  2. 1% increase? Really? I would be interested in knowing the measurement error for the instrumentation on board the satellites. It would be interesting to learn how much of the climate change hype is due to instrumentation (and interpretation) error.

    Gee whiz, it was hot back in the 30s, the 40s, the 50s, the 60s, the 70s, the 80s. What was the cause back then? What was the wind shear in the Jet Stream in the 30s during the dust bowl heat? We don’t know, do we?



  3. 1% increase (instrumentation error plus or minus 2%) will cause a three times increase in CAT? Come on people lets stop believing the hyperbole and use (Common Sense) remember that stuff. We are being played intellectually by the Chinese and Russian Communist to destroy our way of life, so they can rule the PLANET. Sadly our “leaders” are too easily bought and they too want a one world system, because the dream of all these power hungry monsters is to one day “Rule the World”. can you hear “Tears for Fears”?

  4. I reject any ‘research’ that claims a 1% change, in either direction.

    It is not possible to measure the complex varying atmosphere to anything like that accuracy.

    And beware typical statistical analysis is complex, often found botched by Stephen McIntyre at

    But hey! it gets research money from the climate-government complex.

  5. Encounters of turbulence depend on forecasting via ATC and airline dispatch, and fight crew training.

    Injuries also depend on cabin discipline (pax behaviour and F/A activity).

    How is Delta airlines doing? They inherited whatever capability Northwest Airlines still had.

  6. And the politicians like Bouncing Biden and ‘jefe’ Trudeau Jr. are Marxist in underlying beliefs.

    Look at what they advocate in economics and individual rights (they work against rights, they are control-minded).

    They have an anti-human psychology, whereas aviation is built on the human mind’s ability to create and produce.

    • My research concludes with 100% certainty that any story with the slightest whiff of climate change or electric power from those crazy, commie pinkos at Reading University, or Rolls Royce, or the NTSB or (insert your institution of choice here) who want to destroy our way of life, will receive the same thoughtful, well-reasoned response.

  7. I corrected a critical typo – the increase in Professor Williams’s quote is “15 percent more strongly sheared…” not 1 percent. Apologies.

  8. Do you know how big our planet really is? We are microbes on the surface, literally. So acting like we can make a difference one way or the other is still microbial.

  9. I have no problem with the notion that the warming trend (which, yes, is real and has been ongoing since the last ice age peak, doubtless to some degree or other currently accelerated by our activities) is causing some weather pattern changes. What I can’t understand is the fact that – going by the media – climate changes never, ever, even in the slightest way, act or even might act to the benefit of mankind or any other lifeform. Which is strange because fossil records show the warm, wet interglacial periods marked by an explosion of life in vast areas where currently it is rather spare, and humans certainly have the flexibility to cash in on that.

    • It’s not strange. It’s simply become a means to wealth and control. This issue is a pathway to convincing the public (worldwide) that the only way to save the world is by following the guidance of the elite ruling class while they enrich themselves. They use one sided pseudo-political science to bolster their claims making it easier to take more of your money and control every detail of your existence.

  10. Keyboard commandos are finding commies and marxists in the weather services today; tomorrow they’ll be finding them seeding our frippy dippy cones. The horror of it all

  11. Climate change been happening for 4 billion years…nuthin’ new. All these climate change scientists have to keep justifying their gubmint grants.

  12. Whenever I see the word ‘sustainable’ I know it’s the Greenies at work. They’ll ruin our lives, our future and aviation if we give them an inch.