|What is the greenhouse effect?
The Earth would be much colder if it had no atmosphere. The greenhouse effect is the natural tendency of the atmosphere to keep the planet warm, making it hospitable to life.
The Sun emits short-wave radiation (mostly visible and ultraviolet light), which is absorbed by the Earth. This warms the Earth's surface, causing it to emit longer-wave (infrared) radiation.
Some of this infrared radiation escapes through the atmosphere into space. But some is absorbed by greenhouse gases in the atmosphere, which helps to keep the Earth warm.
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