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Summer Sunset Over Okoboji

It was a beautiful August night on Okoboji Lake, Iowa, in the summer of 2022. The water was calm, and the waves were smooth. The temperature hovered around 70 degrees. We observed the sun setting off to the west. The way the sunset reflected off of the water appeared differently, than when it reflected off of the dry land. When we stuck our hand in the water, we could feel it was warmer in the spots the sun was still hitting. It was colder in the darker spots where the sun had already set and it couldn’t reach anymore. 

Okoboji, Iowa

Driving Question

  • Why is the sunlight’s reflection different on the water when comparing the left and right sides of the picture?

Probing Questions

  • Which side is closer to the brightest part of the sunset?
  • Which side is further from the brightest part of the sunset?
  • If we took the boat closer to the sunset,  would the water temperature be warmer or colder?

Classroom Suggestions

Students could:

  • Observe a sunset in their town or nearby lake and see if the land is warmer the closer you get to the sunset.
  • Put a bucket of water outside and see if it gets warmer or colder during a sunset.
  • Compare the reflection of the sun on the land during a sunrise and a sunset. How are they alike? How are they different?

Relevant Related Resources

Iowa Core Alignment

Make observations to determine the effect of sunlight on Earth’s surface

Credit Info

Phenomena submitted by Arielle Sexton.

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