For someone who crosses the Atlantic several times a year, I thought this was interesting. As they noted in the article, the winds across the Atlantic are already stronger and now areas of turbulence will be stronger and more widespread. Indeed on several eastbound transatlantic flights I've taken recently, the NYC-LON flight time was less than westbound transcontinental US flights (e.g. NYC - SFO). In other words, because of stronger winds, I could go from NYC to London faster than I could go from NYC to San Francisco.
Modelling suggested the average strength of transatlantic turbulence could increase by between 10% and 40%, and the amount of airspace likely to contain significant turbulence by between 40% and 170%, where the most likely outcome is around 100%. In other words, a doubling of the amount of airspace affected.
"The probability of moderate or greater turbulence increases by 10.8%," said Dr Williams.
"'Moderate or greater turbulence' has a specific definition in aviation. It is turbulence that is strong enough to bounce the aircraft around with an acceleration of five metres per second squared, which is half of a g-force. For that, the seatbelt sign would certainly be on; it would be difficult to walk; drinks would get knocked over; you'd feel strain against your seatbelt."
Besides passenger comfort, there's also a business consideration here:
"It's certainly plausible that if flights get diverted more to fly around turbulence rather than through it then the amount of fuel that needs to be burnt will increase," he told BBC News.
"Fuel costs money, which airlines have to pay, and ultimately it could of course be passengers buying their tickets who see the prices go up."
Pilots never knowingly fly into or stay in areas of sustained moderate (or greater) turbulence, not because it's dangerous but because it's not fun for the passengers or the cabin crew. So if they have to go further and further north or south to avoid it, then they burn more fuel. And those increased costs will inevitably get passed onto the flying public.