Cavum clouds

Cavum clouds are formed when aeroplanes pass through layers of altocumulus clouds, which are mid-level clouds containing supercooled water droplets.

Cavum clouds
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About Cavum clouds

  • These clouds are also known as “hole-punch clouds or fallstreak holes.”
  • How are Cavum clouds formed?
    • These are formed when aeroplanes pass through layers of altocumulus clouds, which are mid-level clouds containing supercooled water droplets (water below freezing temperature but still in liquid form).
    • As the aircraft moves through, a process known as adiabatic expansion can cause the water droplets to freeze into ice crystals.
    • These ice crystals eventually become too heavy and fall out of the cloud layer, creating a hole in the clouds.
    • These “mysterious clouds” has been ongoing for over 13 years.
    • They are formed when planes pass through at a relatively steep angle.

What are Altocumulus clouds?

  • These are typically found in groups or heaps clumped together.
  • They’re found in the middle layer of the troposphere, lower than cirrocumulus and higher than their cumulus and stratocumulus counterparts.
  • The term mackerel sky is also common to altocumulus (and cirrocumulus) clouds that display a pattern resembling fish scales.
  • These are the one of the most diverse and dynamic in terms of appearance.

Q1) What is the troposphere?

It is the lowest layer of the Earth’s atmosphere in direct contact with the Earth’s surface. Most of the weather phenomena, systems, convection, turbulence, and clouds occur in this layer.

Source: NASA satellite captures ‘odd holes’ in clouds caused by aeroplanes. Explained

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