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As the polar ice caps disappear, the equatorial regions must take the bulk of extra water due to the earth's spin.

My question is will the tilt of the earth be affected and what would be the consequences?

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  • $\begingroup$ The tilt of the Earth is mainly affected by much larger external forces like the distance to the moon . check out en.wikipedia.org/wiki/Axial_precession and perhaps rephrase your question to give more specific conditions. $\endgroup$ – farrenthorpe Dec 5 '15 at 4:07
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    $\begingroup$ I think it's actually incorrect to say the equatorial regions must take the "bulk" of the water. If that was the case, the bulge would grow quite a bit and that's not what's expected to happen. The ocean rise, which so far is still quite a bit smaller than the moon tide, is complicated and distributed unevenly. A more direct effect of melting ice on the poles is the poles become lighter and mass is more evenly distributed, which should slow the Earth's rotation speed. I would guess the effect on the tilt wouldn't be much, but it's an interesting question. $\endgroup$ – userLTK Dec 5 '15 at 15:45
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    $\begingroup$ Curriously the warming of the oceans is expected to cause the Earth to rotate slightly faster - see here. newscientist.com/article/… (though I still maintain, melting ice-caps will slow the spin, at least for a while). here's an article on the uneven sea-level rise so far, (not mostly around the equator) ktuu.com/news/news/… $\endgroup$ – userLTK Dec 5 '15 at 16:02
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An interesting question! I suggest you do some 'slightly complex' calculations. Look up the angular momentum of the whole Earth. Then calculate pM.dF where pM is the additional angular momentum from the melted ice, redistributed as a function of latitudinal angular momentum. dF is differential redistribution caused by continent-ocean constraints. I'm confident that you will find that the additional differential off-axis angular momentum will be miniscule compared to the total. There will of course be some effect upon the Earth's spin axis, but this will be just another of the small catalogue of mass distribution effects which contributes to a somewhat chaotic wobble in the Earth's spin axis, which is typically in the order of a meter or two. When global warming gets worse and huge masses of ice /water are redistributed, then I'm guessing that the effect could be orders of magnitude more - tens or hundreds of metres maybe? Also consider that the Earth behaves like a gyroscope, so much of the additional angular momentum will exhibit as rotation around other axes, much as hurricanes rotate in the atmosphere.

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  • $\begingroup$ From the earth's beginning sea levels have always varied. So , I believe has true and magnetic north. $\endgroup$ – Andy cole Dec 5 '15 at 22:12

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