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Global Warming and the Greenhouse Effect

The earth’s atmosphere keeps the planet warm by a process
called the greenhouse effect. It lets in the sun’s energy in the form
of visible light. When this light hits the earth, it becomes heat.
Greenhouse gases let some of this heat back into space, but trap
some of it within the atmosphere. Burning fossil fuels, such as coal
and gasoline, adds more greenhouse gases, such as carbon dioxide,
to the atmosphere.
Some people think that the increase in the amount of
greenhouse gases may lead to an increase in the world’s
temperature. They call this global warming. They are concerned
that this warming could harm life on earth. However, the earth’s
atmosphere and climate are complicated, and no one can be sure
how much the atmosphere might warm up and much the
atmosphere might warm up and how much harm that could be.

Comprehension Questions

I. Say which of the following statements are false and
which are true. Correct the false statements to make them
true.

1. A process called the greenhouse effect helps keep the
planet warm.
2. The sun’s energy can exist in the form of visible light.
3. Burning fossil fuels cannot add more greenhouse gases
to the atmosphere.
4. The earth’s atmosphere and climate are not
complicated.
5. Some people think that the global warming can harm
life on earth.

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