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Why do lakes form separate layers in warm weather?

A summer lake can have warm water near the surface and much colder water below. Differences in density can resist mixing even when wind disturbs the surface. Explore how layers form and what has to change before the water mixes more deeply.

5–7 min

Questions you could explore

  • What makes one temperature profile easier to mix than another?
  • How can seasonal warming or cooling change the layers in a lake?

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