Why in News? After a Singapore Airlines flight from London to Singapore was hit by sudden and severe turbulence over Myanmar, a Qatar Airways flight from Doha to Dublin encountered severe turbulence over Turkey. Though flights around the world experience varying degrees of turbulence on a daily basis, the recent incidents that result in serious injuries are rarer, pointing towards the impact of explosive growth in air traffic and climate change.

What’s in Today’s Article?

• What is Flight-Turbulence, its Types and Causes?
• Impact of Climate Change on Flight-Turbulence

What is Flight-Turbulence, its Causes and Types?

• Meaning of flight-turbulence:
  • Turbulence is an irregular motion of the air resulting from eddies and vertical currents.
  • It may be as insignificant as minor bumps or severe enough to throw an airplane out of control or to cause structural damage.
  • Turbulence is associated with fronts, wind shear, thunderstorms, etc.
• Effects of flight-turbulence:
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• Types of flight-turbulence:
  • Light turbulence momentarily causes slight changes in altitude resulting in slight bumpiness.
  • During moderate turbulence, aircraft may experience more notable changes in altitude and attitude, but the plane remains well under control.
  • In severe turbulence, there are significant and sudden changes of altitude and attitude, and the aircraft could momentarily go out of control.
  • In extreme turbulence, the plane is violently tossed about and is practically impossible to control.
• Causes of flight-turbulence:
  • Mechanical turbulence: It is the result of friction between the air and the ground - irregular terrain and man-made obstacles - that leads to formation of eddies.
  • Convective or thermal turbulence: It is caused when hot air from certain ground surfaces rises rapidly while cooler air descends, resulting in convective air currents. Frontal turbulence: It is caused by the friction between two opposing air masses and the lifting of warm air by the sloping frontal surface and is most common close to thunderstorms.
  • Wind shear: It is the change in wind direction/ wind speed (in temperature inversion areas, around jet streams, etc) over a specific horizontal or vertical distance.
    • Clear air turbulence (CAT), which can be sudden and severe and is extremely difficult to forecast or see, may be considered as a type of wind shear turbulence.

Impact of Climate Change on Flight-Turbulence:

• Findings of the study: According to some studies, climate change could make turbulence more frequent and severe.
• How can this be claimed?
  • Climate change is strengthening the jet streams that cause turbulence.
  • A large increase in CAT between 1979 and 2020 in the mid and aircraft cruising altitudes.
  • Over the North Atlantic, severe/ greater CAT durations increased by more than 55% over this period.
• Future predictions:
  • The frequency of severe turbulence would increase more than that of light or moderate turbulence.
  • Not only CAT, but also mountain wave turbulence and near-cloud turbulence will intensify due to climate change.