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Cobra800089 t1_j5oh81s wrote

Reply to comment by FootballImpossible38 in What are the forces on Earth’s Inner Core that change its speed? by BayRunner

Yes, and yes. The magnetic field has flipped before, and during the transition the magnetic field is very weak.

However IIRC it takes on the order of hundred to thousands of years, so probably not something we'll have to worry about. Although the timeline in the article OP is referring to seems to state it's happening faster than we previously thought. (IIRC, In the 90's the core was spinning faster than the planet, by 2009 it was spinning slower)

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FootballImpossible38 t1_j5ohryp wrote

thanks. i must have mis-read recent news articles that stated that the core had reversed its spin and was now spinning in the opposite direction. this implied to me that the field reversal must have already happened in short order and so we would have seen the effects of that weakening here on the surface.

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dukesdj t1_j5omgh1 wrote

There is a difference between the inner and outer core. The inner core is approximately solid while the outer core is liquid and is the region that produces the geodynamo. The geomagnetic reversals are more related to the fluid motion in the outer core than the rotation (and/or differential rotation) of the inner core.

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wazoheat t1_j5oxz86 wrote

I'm not going to blame you, the media coverage on this has been atrocious. Willfully misleading I'd say

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FootballImpossible38 t1_j5pbhan wrote

one expects sensationalism out of the National Enquirer, but not from so many of the more (formerly) respected outlets that covered this story. everyone's out for click-bait it seems.

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Clarknt67 t1_j5rf95h wrote

I don’t think the flipping of the magnetic fields poles is at all related to the direction of Earth’s core. I don’t believe the core can change direction or has been asserted to have ever changed direction. I am sure it can slow down and probably speed up, though.

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Cobra800089 t1_j5rhuvv wrote

Thanks for the clarification. It looks like there is no consensus on why the magnetic poles flip.

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Clarknt67 t1_j5s09as wrote

I agree. I don’t think the magnetic field is definitively understood. Oddly. Since it’s all around us.

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