Lesson · Grade 7 · Science
The Greenhouse Effect
- Grade 7
- Science
- 1 min 9 s
- British Columbia
- BC7-SC-39
A labelled diagram builds up step by step: sunlight passes through the atmosphere and warms the ground, the warm ground gives off infrared heat, and some of that heat escapes to space while greenhouse gases absorb some and send part of it back down. It compares Earth's average temperature without greenhouse gases (about −18 °C) and with them (about 15 °C), then shows how burning fuels adds carbon dioxide that traps more heat and makes Earth warmer.
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In one sentence
The question this lesson answers
What keeps our planet warm enough for life?
Earth is wrapped in a thin layer of air called the atmosphere.
Transcript
What the lesson says
What keeps our planet warm enough for life?
Earth is wrapped in a thin layer of air called the atmosphere.
Sunlight passes through the air and reaches the ground.
The land and oceans absorb the light and warm up.
The warm ground then gives off heat as invisible infrared rays.
Some of this heat escapes into space.
But greenhouse gases in the air, like carbon dioxide, absorb some of the heat.
They send part of that heat back down to the ground.
This is called the greenhouse effect.
Without greenhouse gases, Earth would average about minus 18 degrees Celsius.
With them, the average is about 15 degrees Celsius.
Burning coal, oil and gas adds more carbon dioxide to the air.
More greenhouse gas traps more heat, so Earth is getting warmer.
Greenhouse gases trap heat, so adding more of them makes Earth warmer.
Curriculum
Where this fits
- British Columbia, Grade 7
Science, Earth science: evidence of climate change over geological time and the recent impacts of humansBC7-SC-39
Previous: Weather and climate: today's air versus the pattern over many yearsNext: Reading Past Climate: Ice Cores, Tree Rings and Fossils
- British Columbia, Grade 9
Science, Earth science: sustainability of systemsBC9-SC-32
Previous: Dynamic equilibrium: balanced but always changingNext: How People Tip the Carbon Balance
This lesson is also listed in Grade 9.
The outcomes and strands follow the British Columbia curriculum.
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