“So the question is: how much does the Earth’s internal (core) heat contribute to the warmth on the surface of the Earth?”
It’s a smaller factor than the sun’s heat by far, but it does make some not insignificant contribution.
“if our inner core’s heat should suddenly die, could humans survive using only the Sun’s heat?”
We probably could, but any interruption in the balance and feedback cycles could be far ranging, because each element has effects on the other elements in the system, and we definitely do not understand all of the interdependencies of the system in great detail.
The real problem if the core “went out” is that we would probably no longer have a global magnetic field protecting the earth, since that seems to be generated only by an active molten core. No magnetic field would mean very little protection from the solar wind, so more of our upper atmosphere would be stripped off, and more UV radiation would be bombarding the surface. That’s a pretty deadly combination that would probably lead, in time, to the Earth looking a lot more like Mars.
“if our inner core’s heat should suddenly die, could humans survive using only the Sun’s heat?”
Oh great, now their going to blame me for global warming because, I suck water out of the ground robbing the earth of it’s core coolant.
Wow, some great answers! And fascinating to learn how interdependent all these natural forces are in making our planet habitable.
And there I was, a sailor with a trusty magnetic compass on my ship’s bridge with no idea the magnetic field was protecting me.
I’ll bet 90% of all laymen who argue about climate change (one way or the other) have never heard of the magnetic field’s positive contribution. I certain heard nothing about this in high school, but it seems like essential scientific knowledge.
Now, do we know if moons and planets in our Solar System are also protected by a molten core of iron creating their own magnetic fields?