The data seems to show a significant increase in clear-air turbulence, apparently due to increased energy in the system from climate change. I have heard people say "when you add energy into a chaotic system, it becomes more chaotic."
> Moderate turbulence increased by 37%, and light turbulence increased by 17% during this period. Other flight routes over the U.S., Europe, the Middle East, and the South Atlantic also significantly increased.