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Strange and rare ‘hole’ photographed in clouds over Paris
This meteorological phenomenon occurs when water droplets in the cloud freeze and fall
A rare hole formed in the clouds over Paris on Monday morning (October 16). The meteorological phenomenon known as ‘skypunch’ was captured on photograph, not far from the Eiffel Tower.
The circular gap was several kilometres in size and resulted from ice crystals forming and falling from within the middle of the cloud layer.
How the ‘hole’ formed
Skypunch holes form in specific clouds (stratocumulus, cirrocumulus or altocumulus) composed of supercooled water droplets, water below 0°C but not yet frozen.
When these water droplets do freeze they grow and become much heavier until they eventually fall, leaving a hole behind.
As neighbouring droplets start to freeze the hole will expand, which explains the gap being kilometres wide.
Natural or not?
Supercooled water droplets need a reason to freeze, which usually comes in the form of ice crystals.
Planes passing through the cloud layer can bring these ice crystals, as they create a drop in pressure which consequently lowers the temperature.
The phenomenon can have a natural origin as well if there is a large supply of ice nuclei in the atmosphere – these are tiny grains which promote the formation of ice crystals. In this case all the drops in a cloud will freeze instantly.
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