• disguy_ovahea@lemmy.world
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    6 months ago

    Are you referring to the magnetic pole switch? That happens every 200-1M years, according to patterns on the seafloor. It’s been estimated that the last reversal was 780,000 years ago, so it theoretically could be any day now.

    With that being said, I doubt that humanity will agree to turn all maps 180° to correspond.

    • pacmondo@sh.itjust.works
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      6 months ago

      I thought they were referring to the fact that under the ice its an archipelago, so if the ice melts it will have southern coasts again

      • fishos@lemmy.world
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        6 months ago

        If it melts, they’d all be northern coasts.

        It’s referencing the pole swap.

        • The_Lorax@sh.itjust.works
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          6 months ago

          Since it’s an archipelago underneath then most, if not all, of those islands would have a southern coast. The only way to not have a southern coast is to have the landmass directly on top of the pole, which could only happen for one island (if no ice is present)

          • disguy_ovahea@lemmy.world
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            6 months ago

            To move a continent north of the equator at the rate of 1 CM per year? You might need a bigger napkin.

            Antarctica’s leading coast is 10,000 KM from the equator. Assuming it’s able to continue through Southern Africa at the same rate, it would take 100 billion years to have a northern coast.

            • fogstormberry@lemmy.blahaj.zone
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              6 months ago

              southern or northern coast. I had deleted my comment already because I misread yours, but I had mathed the time to move away from the pole, producing a southern coast. not time to cross the equator

              • disguy_ovahea@lemmy.world
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                6 months ago

                You’re right, that would create a northern coast. That would be closer to 300M years, assuming it can continue to move at the rate of 1 CM/year, straight through Africa. Antarctica is ~4,500 KM across. The leading coast is only 1,287 KM from the South Pole, leaving 3,213 KM of land needed to migrate from the Pacific side. That would take 321,300,000 years.

    • veroxii@aussie.zone
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      6 months ago

      I was referring to continental drift. Places move a lot in under 200 million years. Eg https://youtu.be/uLahVJNnoZ4

      So my post was a bit sarcastic that eventually it will have a coast but not on any time frame to matter to the human species. :)

    • fossilesque@mander.xyzOPM
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      6 months ago

      Laschamp event! I just edited a related wiki page on late Pleistocene extinctions. Spoiler alert: it didn’t kill the megafauna.