 The
Greenhouse Effect
The glass windows of a greenhouse let in sunlight. The sunlight
warms objects inside the greenhouse. These objects then give
off heat.
The glass of the greenhouse, however, does not let the heat
out. If the greenhouse lacks ventilation, the heat stays locked
inside and the temperature rises.
The Earth and its atmosphere are like a giant greenhouse. Like
the glass windows of a greenhouse, the atmosphere lets in the
sunlight that heats the Earth. Then, like the glass windows
of the greenhouse, the earth’s atmosphere traps the heat
that radiates from Earth. This heat-trapping mechanism is called
the greenhouse effect and is critical to life on Earth. Without
it, the planet would be much colder – too cold to support
life as we know it.
Can you show the greenhouse effect?
• Two identical glass jars
• Four cups cold water
• 10 ice cubes
• One clear plastic bag
• Two thermometers
1. Pour two cups (500ml) of cold water into each jar.
2. Add five ice cubes to each jar.
3. Wrap one jar in the plastic bag (this is the greenhouse glass).
4. Leave both jars in the sun for at least one hour.
5. Measure the temperature of the water in each jar.
Which is warmer?
What does this indicate about the greenhouse effect? |
|
