Earth's Magnetic field and Climate change seem to be linked

[Eastoff]

http://physics.aps.org/articles/v6/103
I don't think there is a chicken or the egg yet though.

 

[BrianFromWA]

the sad thing is that, instead of talking about the science, people will turn this into either a defense of their belief or a point to be defended against.

 

[BrianFromWA]

But I'm slightly confused by one point...why would ice accumulating at the poles have an "ice skater pulling arms in" effect? The ice skater is just maintaining angular momentum, increasing angular velocity as a square of the radius decrease of the outlying mass. But if water is moving, say, in the most extreme mode, as water from the equator to ice on the poles, the radius difference is 21km (about 1/2 of 1% of earth's diameter). Does that really justify an increase in angular velocity that would heavily impact magnetic fields? It would be the equivalent of an ice skater doing everything the same except making fists instead of fingers-out.

I'm much more inclined to gut-feel it by saying that solar 'happenings" are much more likely to have a large effect on the magnetic field, which would then cause shifting in the lead-based core, causing rotational increases (or more likely, "wobbles"). But that's just a gut feeling.

 

[Denny Crane]

Spinning ice skater goes faster when she holds her hands closer to her body instead of outstretched. So you'd think moving water from the equator to the polls would have a similar effect.

 

[BrianFromWA]

as I said, the difference in "closeness" to center of mass is 1/2 of 1%. Or the same as if she closed her fist, not pulled her arms in.

 

[Denny Crane]

The mass of the water moved to the pole (axis) is like the skater pulling her hands closer to her body (axis).

EDIT: pulling her hands PART WAY closer to her body.

 

[Eastoff]

But I'm slightly confused by one point...why would ice accumulating at the poles have an "ice skater pulling arms in" effect? The ice skater is just maintaining angular momentum, increasing angular velocity as a square of the radius decrease of the outlying mass. But if water is moving, say, in the most extreme mode, as water from the equator to ice on the poles, the radius difference is 21km (about 1/2 of 1% of earth's diameter). Does that really justify an increase in angular velocity that would heavily impact magnetic fields? It would be the equivalent of an ice skater doing everything the same except making fists instead of fingers-out.

I'm much more inclined to gut-feel it by saying that solar 'happenings" are much more likely to have a large effect on the magnetic field, which would then cause shifting in the lead-based core, causing rotational increases (or more likely, "wobbles"). But that's just a gut feeling.

Well they did say it was a theory on why. I think solar events would be smaller impact though.

 

[magnifier661]

Way over my head. Can someone explain this to me?

 

[Eastoff]

Way over my head. Can someone explain this to me?

When the mass of the water shifts from around the equator to freezing on the ice caps, the distribution of the mass of the earth as a whole shifts to being closer towards the spinning of the planet. When the earth spins faster, the magnetic field changes as well.

 

[Further]

It's interesting. It goes directly against what I learned in a geology course I took about a decade ago. This was actually asked, or a version was asked, and the professor said there did not appear to be any link. Anyway, pretty interesting, and seems more likely to be correct than a PSU prof, a decade ago.

However, to actually shift polls completely, takes thousands of years. Many people think of it as a flipping of a switch, but that's not the case. At least that hasn't been the case so far as we can tell. That does not mean that a more aggressive climate change wouldn't give rise to a faster poll switch, I just don't know.

 

[magnifier661]

When the mass of the water shifts from around the equator to freezing on the ice caps, the distribution of the mass of the earth as a whole shifts to being closer towards the spinning of the planet. When the earth spins faster, the magnetic field changes as well.

Now I get it. That makes sense now. I was reading the article and was like "WTF is he saying?!?!"

I thought the mass of Ice is less dense than the mass of water? How would that make the earth spin faster? I suspected the mass of earth was less dense at the center?

 

[MarAzul]

But I'm slightly confused by one point...why would ice accumulating at the poles have an "ice skater pulling arms in" effect? The ice skater is just maintaining angular momentum, increasing angular velocity as a square of the radius decrease of the outlying mass. But if water is moving, say, in the most extreme mode, as water from the equator to ice on the poles, the radius difference is 21km (about 1/2 of 1% of earth's diameter). Does that really justify an increase in angular velocity that would heavily impact magnetic fields? It would be the equivalent of an ice skater doing everything the same except making fists instead of fingers-out.

I'm much more inclined to gut-feel it by saying that solar 'happenings" are much more likely to have a large effect on the magnetic field, which would then cause shifting in the lead-based core, causing rotational increases (or more likely, "wobbles"). But that's just a gut feeling.

The power require to spin and object at a given velocity, increase by a power of 2.6 of the diameter. Therefore a reduction in diameter of .5% would result in an increase in rotation speed by well over 1%, more than enough to significantly effect induction in the big generator.

 

[MarAzul]

The power require to spin and object at a given velocity, increase by a power of 2.6 of the diameter. Therefore a reduction in diameter of .5% would result in an increase in rotation speed by well over 1%, more than enough to significantly effect induction in the big generator.

Data from the Mark1A