Climate Change Affects Jet Streams Causing More Air Turbulence

Climate change is increasing the risk of clear-air turbulence, resulting in bumpier flights for airlines and their passengers. As the atmosphere becomes less stable, aviation experts warn that turbulence levels will continue to rise in the coming decades.

How climate change is affecting the jet stream

A new study from the University of Reading, building on previous research that reported an increase in jet stream vertical wind shear, explores how these trends will evolve under future climate conditions.

The study, Future Trends in Upper-Atmospheric Shear Instability from Climate Change, published on 19 August 2025, used 26 of the latest global climate models to analyse how rising temperatures influence jet streams at typical cruising altitudes of around 35,000 feet.

The jet stream is a fast-moving ribbon of air located 9–16 km above the Earth’s surface, flowing from west to east at speeds of 100–400 km/h. Wind shear, sudden changes in wind speed or direction, can occur vertically or horizontally and is a major driver of turbulence during flight.

Why the jet stream is changing

The researchers focused on trends in vertical wind shear in the upper troposphere and lower stratosphere, both globally and across specific latitude bands. They aimed to understand how the meridional temperature gradient, the temperature difference between the equator and the poles, is shifting as the climate warms, and how this affects jet stream stability.

Traditionally, the strong temperature contrast between the warm equator and the cold poles powers the jet stream. However, Arctic amplification, in which the Arctic warms faster than the global average, is weakening this gradient.

A reduced temperature gradient slows the jet stream and makes it more wavy. A wavier jet stream increases vertical and horizontal wind shear, creating unstable atmospheric layers that are conducive to clear-air turbulence. Unlike turbulence caused by storms or clouds, clear-air turbulence (CAT) is invisible and therefore difficult for pilots to detect in advance.

What the study found

Using simulations from CMIP6 climate models, the study found that:

• Wind shear is projected to increase by 16–27% from 2015 to 2100.
• Atmospheric stability is expected to decrease by 10–20%.

These changes suggest that conditions will become increasingly favourable for clear-air turbulence. For airlines, this could lead to more mid-flight injuries, higher fuel consumption, and increased aircraft wear and tear. For passengers, it means a greater likelihood of experiencing unexpectedly bumpy flights, even on seemingly clear days.

As the climate warming trend continues, understanding how turbulence patterns are evolving will be essential for improving aviation forecasting, safety, and long-term planning..

Read the study: Future Trends in Upper-Atmospheric Shear Instability from Climate Change.