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Greenhouse Effect

Replicate the greenhouse effect on a small scale, without the need for greenhouse gases

Australian Curriculum links

  • Science > Earth and Space Sciences > Year 3 > ACSSU048
  • Science > Earth and Space Sciences > Year 10 > ACSSU189
  • Mathematics > Measurement and Geometry > Year 4 > ACMMG084
  • Science > Senior secondary curriculum > Earth and Space Sciences > Unit 2: Earth processes – energy transfers and transformations

You’ll need

  • Large glass jar
  • Strong lamp (120 watt) or a sunny spot
  • 2 thermometers

Try this

  1. Place two thermometers in front of the lamp or in the sun and record the temperatures of both.
  2. After a few minutes cover one thermometer with a glass jar (you may need to stand the thermometer up).
  3. Record the temperatures of both thermometers every minute for at least 10 min.

What’s happening?

The heat energy from the lamp or sun passes through the glass and some of the heat energy is trapped inside. This warms the air inside which is unable to mix with the cooler air outside the jar. The glass simulates the layer of greenhouse gases in the atmosphere that trap heat energy.

Greenhouse gases trap heat from the sun in our atmosphere. This is a natural process keeping the average global temperature at around 15°C. Without the natural greenhouse effect the average temperature across the planet would be -17°C, meaning the world would be covered in ice!

However, the greenhouse effect has been enhanced by human activity like burning fossil fuels, tree clearing and farming cows and sheep.

Modern transport, manufacturing and agricultural practices produce large amounts of several greenhouse gases, mainly carbon dioxide (CO2), methane and nitrous oxide. These occur naturally in the atmosphere, but levels are now higher than they have been in the last 650 000 years.

The unnaturally high concentration of greenhouse gases currently in the atmosphere is causing more heat to be trapped. This is called the enhanced greenhouse effect. The enhanced greenhouse effect has caused the average surface temperature of the Earth to rise 0.76°C since 1850.