Clouds, however, which cover about half of the earth ’ s surface, have an average emissivity of about 0. 5 ( which must be reduced by the fourth power of the ratio of cloud absolute temperature to average earth absolute temperature ) and an average cloud temperature of about.

Clouds, however, which cover about half of the earth ’ s surface, have an average emissivity of about 0. 5 ( which must be reduced by the fourth power of the ratio of cloud absolute temperature to average earth absolute temperature ) and an average cloud temperature of about.

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