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My eight year old is doing a report on clouds and condensation, evaporation, and how it all works. Can you help us out?
Thanks.
Jack R.
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The easiest way to answer this one is to point you in the direction of our good friend the water cycle. As the sun heats up the oceans, we then evaporate some of that water. As that rises and cools and condenses, we then form clouds. Clouds will rain and the cycle starts again.
Clouds form when the water vapor condenses onto something in the air. But to form that cloud droplet we need what's called Cloud Condensation Nuclei or CCN for short. This can be anything like dust, volcanic ash, factory smoke or salt. Cloud droplets are actually much smaller than rain droplets.
Evaporation is the process of when liquid water changes to a gas, we call that gas water vapor. Rember, water can exist in three phases, liquid, solid or gas. Evaporation is also a cooling process, this is why after you take a bath you start to get cold if you just stand there, the water is evaporating off of you.
Condensation is the opposite. This happens when water goes from a gas back to a liquid. Think of a glass of ice water which forms liquid on the outside of that glass. Did the liquid move through the glass? Clearly, the water vapor was already in the air, the water vapor on that glass was cooled to its dewpoint and condensation or sometime what people call "sweat" has happened.
Answered by KSL Meteorologist Dina Freedman
