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p9107
2002-Apr-18, 07:25 AM
What would happen if the centre of the earth cooled down? Would we all die? Or would the sun's heat keep us alive?

Ad Hominid
2002-Apr-18, 09:30 AM
Practically all the energy that keeps us alive comes from the sun now. Except for localized hotspots like volcanoes, the Earth's internal heat makes almost no contribution to warming the surface and the atmosphere. If anything, internal heat makes the Earth's surface a little cooler, since it is the source of volcanic activity, and volcanic dust blocks sunlight.

p9107
2002-Apr-18, 10:49 AM
So would we be able to survive?

GrapesOfWrath
2002-Apr-18, 11:03 AM
Sure. Given the right conditions.

On the other hand, it takes a long long time for the Earth to cool. The heat that starts at the core takes a billion years to travel to the surface. Kelvin actually tried to use the heat loss of the Earth to estimate the age of the Earth--but he didn't account for radioactive decay. Even if the Earth were losing heat at the rate it seems to (because of the high concentration of radioactivity in the crust), it would still take a very long time to cool--as Kelvin showed over a hundred years ago.

p9107
2002-Apr-18, 12:06 PM
Okay, so now I know - Thanks!!


<font size=-1>[ This Message was edited by: p9107 on 2002-04-18 08:07 ]</font>

John Kierein
2002-Apr-18, 12:48 PM
Maybe the earth inside isn't cooling. Maybe it's heating and growing more massive from Pushing Gravity.

Silas
2002-Apr-18, 01:38 PM
If the center of the earth were cool, the plates would stop moving, and mountains would begin to erode. The rivers would silt up, and the world would become a bit marshy... I've heard that, without geological building processes, the world would reach an erosional steady-state in about 100,000 years...

Silas