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Transcriber: TED Translators Admin Reviewer: Rhonda Jacobs
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Why is the world warming up?
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Let's think of Earth for just a moment as a greenhouse.
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Every second, a huge amount of energy smashes into our greenhouse.
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Our atmosphere, the glass roof and walls,
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reflects some of that energy,
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but most of it passes right through and heats everything up.
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Much of that heat used to escape back into space,
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keeping us at a stable, warm temperature.
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But then something changed.
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Humans began to spew enough carbon dioxide to fill billions of greenhouses each day.
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What does all that greenhouse gas do?
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It makes the glass of our greenhouse thicker.
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Thicker glass means heat escapes into space much more slowly.
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And don't forget, energy from the sun
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is still streaming in just as quickly as before.
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The result is a planet with temperatures too hot for our liking
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and, eventually...
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living.
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Take action on climate change at Countdown.ted.com]