The Sun emits approximately 1361 watts per square meter on Earth. I read in a book that since the Earth is approximately a sphere and only half of it is being illuminated by the Sun, the solar irradiance at the lit side of Earth is reduced by half (so around 680 watts per square meter). Is this correct? I thought the solar irradiance is a constant per square meter. So if the Earth is to be fully illuminated, the total power received by Earth from the Sun would be 1361 watts per square meter times the area of the Earth, I think this value should be the one to be reduced to half when only half of Earth is illuminated (i.e. 1361 watts per square meter times the area of the lit side of Earth)(adsbygoogle = window.adsbygoogle || []).push({});

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# Confirmation on the Effect of Solar Irradiance

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