MadSci Network: Astronomy |
You can estimate the effect of a change in the distance from the Earth to the Sun by using a scaling relationship much used in climate research.
If the input of light from the Sun changes by 1% there will be a (roughly, very roughly) 1 degree C change in temperature. Since the amount of light we receive is inversely proprotional to the square of the distance to the Sun we can work out that a 1/2% change in the distance to the Sun will cause a 1% change in the amount of light we receive. So, as the distance to the Sun from the Earth is about 150 million kilkometers we work out that 1/2% of that distance is about 3/4 million kilometers, which is about 100 times the Earths radius.
Therefore, a 1 degree C temperature change could be induced by a change in the Earth's distance to the Sun by the above amount, and not a few centimeters as you were told!
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