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Earth as a blackbody. The Earth (and other planets) also act as a blackbody, usually with emissivity. Calculate the power emitted by a square kilometer of ocean surface at 10 0 C if its emissivity is 0.65. 2. Calculate the power radiated by the Earth if it is taken to be…
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The Earth (and other planets) also act as a blackbody, usually with emissivity.
Calculate the power emitted by a square kilometer of ocean surface at 100C if its emissivity is 0.65.
2. Calculate the power radiated by the Earth if it is taken to be… a) a perfect blackbody b) a blackbody, with emissivity of 0.62
If we say the average power, incident on the Earth, is 1.23 x 1017 watts, and the emissivity is 1 (power in=power out), what would be the equilibrium temperature of the Earth? (Radius of Earth:6.38 x 106m)
So…255K, that’s -18° C. Too cold. The average equilibrium temperature of Earth is actually measured at 288 K. Calculate the emissivity of the Earth. • What causes this?