Air turbulence to rise due to climate change

As climate warms, researchers cautioned that the invisible, unpredictable form of air turbulence is expected to occur more often in most northern mid-latitude regions, thereby impacting aviation.

Between 1980 and 2021, instances of planes experiencing clear air turbulence increased by 60- 155 per cent across regions in the Northern Hemisphere, according to a new research.

As climate warms, researchers cautioned that the invisible, unpredictable form of air turbulence is expected to occur more often in most northern mid-latitude regions, thereby impacting aviation.

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Clear air turbulence is seen to happen near fast-moving, west-to-east air currents, or ‘jet streams,’ in the upper troposphere — the region in the Earth’s atmosphere where commercial planes fly, about 10-12 km or 32,000-39,000 feet above ground.

Planes passing through such jet streams can experience “spikes of volatile, upwards-moving air” called vertical wind shear, thereby causing turbulence.

The researchers explained that in a warmer climate, energy in the atmosphere will be more, thereby increasing the speed of jet streams and the number of vertical wind shears. This meant that with each degree of global warming, the likelihood of planes encountering clear air turbulence will increase.

Clear air turbulence also hits an aircraft unexpectedly, as unlike other, more obvious forms of turbulence — such as that due to flying through a thunderstorm or over a mountain range, this form is not easily detected and thus, harder to be avoided, the researchers said.

The invisible form of air turbulence is presently most frequent over East Asia, where the subtropical jet stream is the strongest, the authors said, citing recent examples of Singapore Airlines and Air Europa flights.