Physics Stack Exchange is a question and answer site for active researchers, academics and students of physics. It's 100% free.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

What effects would occur if the earth's core goes cold? Would the planet stay liveable after this happens?

share|cite|improve this question
up vote 12 down vote accepted

Once the core has solidifed it can no longer generate a magnetic field. There may be some frozen in field, but I would guess that the strength of the magnetic field with decrease as more and more of the core freezes, so any residual field is likely to be small. The core of Mars is thought to be frozen and it's magnetic field is negligable.

Anyhow, the main problem would be that without the magnetosphere to protect it the atmosphere will gradually be stripped by the solar wind and we'll be left with nothing to breathe. In addition, without an atmosphere the surface will be subject to wide temperature swings; just as the Moon is in fact.

So no, by any reasonable definition of the word liveable once the core has frozen the Earth will not be liveable. I wouldn't worry for a while yet though.

share|cite|improve this answer
It is not necessary for the Earth's core to freeze for the geomagnetic field to collapse. The geomagnetic field is a chaotic phenomena and has reversed polarity many times in the Earth's history. The question is why are we so fortunate to have a persistent geomagnetic field at all? I believe Mars has a molten core, but a much weaker magnetic field than Earth. Mars lacks a natural satellite as large as Earth's Moon. What role has our Moon played in creating a persistent geomagnetic field? There's a worthy geophysical question! – Mark Rovetta Mar 2 '13 at 2:02

I am not educated in this field but I suggest that the moon acts upon the liquid earth outer core much like it does upon our oceans, acting as a mixer therefore constantly stirring the molten pot if you will. The liquid is thus ever moving within the mantle causing a more consistent and uniform magnetic field.

share|cite|improve this answer
Well that's basically the tidal force you're discussing, but this answer doesn't really address the question at hand, which is about the effects of earth's core cooling. – Kyle Kanos Oct 5 '15 at 17:43

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.