With the recent wet weather around the world, it reminded me of a time when a preschooler asked me why does the sky rain? (The explanation I used at the time was a bit NSFP, Not Safe for Polite Company. Its included at the bottom if you need to grab the attention of a restless preschooler.)
Rain basically is water going through evaporation (turning from water to steam, aka boiling) and condensation (turning from steam to water, aka fogging up) cycle. Water gets made into steam in the air from any source of water (e.g. lake, ocean or even just moisture on the pavement). If the environment doesn’t change, it will stay in the air for a long time, hanging around in the form of clouds. However it will usually meet something that causes the steam to cool. This cooling then turns the steam back into water, falling to earth. So at a simplistic level, you can say that cloud drinks water when it is warm, and when something cools it down it rains.
In a way this continues non-stop throughout the world. What is evaporated from the pacific ocean today may fall as rain in Asia tomorrow.NSFP Analogy
If the preschooler is at a stage when any bodily functions are a hilarious topic, the following may work well.
When its warm, the cloud drinks water (from evaporation, you may have to do some ground work here) just like a person does. Until they drink so much water that their body can’t hold anymore. They have to go to toilet to get rid of the excess water. Then the cloud goes to toilet, producing rain.
Its simplistic… but they won’t forget it in a hurry. 🙂
Let us know any strange analogy you ever had to use to explain a concept to a child.Sneak Preview - As Promised