A Wonderleaf question
Why is fog close to the ground?
a real page from the book
Fog sits low because it forms where damp air has cooled enough for water vapor to become tiny droplets. On many mornings, the ground loses heat overnight, chilling the air right beside it first, so the new cloud appears near your ankles instead of overhead.
Those droplets are so small that they hang in the air instead of quickly raining down. As sunlight warms the ground again, the droplets turn back into invisible vapor, and the fog thins, lifts, or disappears. In plain terms, fog is a ground-level cloud.
Wonder words
- vapor
- droplets
- condense
- radiate
Try it out
On a cool evening, breathe gently onto a window or mirror and watch water appear where warm damp air meets cold glass.
Read the whole picture book
Watercolour scenes, straight answers, about three minutes cover to cover.
Open the picture bookKeep wondering
- Why do mountains change the weather?
- Why is frost sparkly?
- Why is the sky sometimes gray?
- Why do clouds change shape?
- How do meteorologists predict the weather?
- Why does the air smell different after rain?
One more wonder: Why is space so dark?
And the next question?
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