Volcanoes, Bicycles, and Monsters: The Year Without a Summer

In our "Volcanoes, Bicycles, and Monsters" episode, we learned how a massive volcanic eruption caused a "Year Without a Summer." Now, let's explore how something blocking the sun can affect our planet!

The Big Question

How does blocking sunlight make things colder?

What You'll Need

• Two jars or clear cups
• Two thermometers
• A sunny spot
• A dark piece of paper or cloth (big enough to cover one jar)

Mission Steps

1. Set Up Jars. Place one thermometer inside each jar.
2. Find Sunlight. Put both jars in a sunny spot where they will get direct light for at least an hour.
3. Block the Sun. Cover one jar completely with the dark paper or cloth.
4. Check Temperature. After an hour, carefully check the temperature reading on both thermometers.

Talk About It

• What was the temperature in the sunny jar compared to the covered jar?
• Why do you think the covered jar was colder?
• How is this like the ash cloud from Mount Tambora blocking the sun?

Take It Further

For older rangers, try covering the jar with different colored transparent materials (like colored plastic wrap). Does color make a difference in how much heat is blocked? Think about how different colors of clothing affect how hot you feel in the sun.

FAQ

Q: Do I need to use actual thermometers? A: Yes, to get a measurable difference, actual thermometers are best. You can find inexpensive ones at a grocery or hardware store. Q: Can I do this on a cloudy day? A: It's best to do this on a sunny day to clearly see the effect of blocking the sun. A cloudy day already has less direct sunlight. Q: What if I don't have two thermometers? A: You can try one jar in the sun, and one jar kept inside, away from the sun, as a comparison.