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Just curious why clouds appear flat on the bottom?
Thanks,
Russ L.
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If you ever have observed clouds, maybe just to see if they look like a shape or an animal, you might notice that the bottom of the cloud looks flat. Clouds can grow vertically and still stay flat on the bottom. Sometimes clouds can look pointy on the bottom too if some of the moisture is falling out and evaporating in the air, we call that virga and we'll save that for another day.
We must remember what clouds are made of, for today we'll consider lower clouds which are made of water droplets. Water exists in three phases: liquid, gas and solid. Water is in its gaseous state all the time, meaning that water vapor is around us everywhere even when it feels dry.
Remembering that clouds form when water goes from a gas phase to a liquid phase or what we call condensation. When water vapor in the air reaches its dewpoint, it will then condense onto tiny dust particles or any sort of cloud condensation nuclei and form a cloud.
Temperatures in the atmosphere change with height. If you were to climb a mountain it usually gets colder as you go up. Temperature in the horizonal, say from you, over to your friend 100 yards away doesn't vary as much. Because that temperature in the horizontal is uniform, the point which water vapor condenses and forms a cloud will be at the same level, or the cloud will appear flat on the bottom.
Some links on the right to some cool cloud pictures.
Answered by KSL Meteorologist Dina Freedman.
