The sun continuously radiates energy into space, some of which is intercepted by the earth. the average temperature of the surface of the earth remains about 300k. why doesn't the earth's temperature keep rising as it continues to intercept the sun's energy?

Because of the reflects back into space equal amount of radiation as it receives.

Explanation: The Earth's temperature doesn't keep rising because as the Earth receives the radiation from the sun, the Earth reflects back an equal amount of that radiation back to space.

This reflective ability of a planet of the sun radiation incident on it is known as the albedo.

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