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If the earth did not have atmosphere, the temperature would be

Asked in GUJCET 2007 · Uses and atmospheric effects

Answer: (2) less

Step-by-step solution

Sunlight arrives mainly as visible and near-infrared radiation and warms the ground.

Idea: the warmed ground radiates in its turn, but at its own low temperature that emission lies far out in the infrared.

Carbon dioxide and water vapour absorb strongly in the infrared and send part of it back down, so the surface has to sit at a higher temperature before as much energy escapes to space as arrives from the Sun.

Take the atmosphere away and that trapping goes with it: the surface then loses its heat freely to space.

So the temperature would be less.

Why the other options are wrong

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