claim: Yet clouds reflect about seventy-five watts per square meter.
evidence: If the extraterrestrial solar radiation is 1367 watts per square meter ( the value when the Earth–Sun distance is 1 astronomical unit ), then the direct sunlight at Earth's surface when the Sun is at the zenith is about 1050 W / m2, but the total amount ( direct and indirect from the atmosphere ) hitting the ground is around 1120 W / m2.