Скачать или смотреть What is a Contrail?

Ever noticed long, skinny white clouds trailing behind planes? These are contrails : condensation trails formed from jet engine exhaust. Learn how they form, what affects their appearance, and their impact on our skies!

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When you look up in the sky,
do you ever see a long, skinny, white cloud?
It could be a condensation trail, or contrail.

Contrails are trails of condensed water vapour, created by the engines of jet airplanes.
How long they last, what they look like, and if they even appear at all, depends how cold and wet the atmosphere is.

Contrails are most often seen along regularly used flight paths.
And as travel by airplane has increased around the world, contrails have become much more common.

They form between 6 and 12 kilometers above the earth’s surface, where the air temperature is well below freezing.

When jet engines burn fuel for power, the chemical reaction of burning the fuel creates water vapor, which is released into the atmosphere.

And when it’s cold enough, and the air is holding lots of moisture, the water vapour from the plane’s engines freezes into ice crystals and forms into these long clouds.

When the humidity is low, the dry air absorbs the water vapour, and the contrails disappear quickly.


When the humidity is high, the already wet air can’t absorb the water vapour, so the contrails can stay for a long time.

Under the right conditions, contrails can last for several hours, spread out, and even grow to become cirrus clouds.

So the next time you see these long, skinny, white clouds, you’ll know what they are, and how they were created.
Just trails of condensed water vapour, left behind by airplanes.

Contrails.