# How much of the Earth's heat is caused by the hot centre?

What is the percentage of the Earth's warmth that the Earth's hot centre is responsible for? What would be the temperature of the atmosphere if the Earth's centre was 18° C (average temperature on the surface)?

• partly relevant : i.imgur.com/wUb82yS.png Jan 9, 2017 at 8:19
• @shrey Could you please share the whole document Jan 9, 2017 at 11:51
• (around pg 221 ) -- elibrary.bsu.az/azad/new/2194.pdf Jan 9, 2017 at 11:59
• 0.03% per Wikipedia: en.wikipedia.org/wiki/… Jan 10, 2017 at 2:32
• Why ask such a what-if about an 18° C core? Jan 26, 2017 at 17:56

Given the insulating effect of 6370 km of rock (the average radius of the Earth) & its low thermal conductivity, if the temperature at the center of the earth was 18 °C it contribution to warming the atmosphere would be negligible.

The temperature at the center of the Earth is about 7000 °C, while the average temperature of the surface is about 10 °C. So if the temperature at the Earth's center was 18 °C its contribution to the surface temperature would be exceedingly small.