Comment on xkcd #3135: Sea Level

Quilotoa@lemmy.ca ⁨2⁩ ⁨months⁩ ago

• Olhonestjim@lemmy.world ⁨2⁩ ⁨months⁩ ago

  See, that’s the part that confuses the hell outta me. How can water be higher in one spot than others just due to the Moon’s gravity? Yeah it’s the geography of the area, got it. But still, how?

  source

  • leftzero@lemmy.dbzer0.com ⁨2⁩ ⁨months⁩ ago

    Ever seen a ferrofluid, which follows the shape of magnetic fields? Same thing, but with gravity.

    Of course, that only accounts for a fraction of those 16 meters… but there’s a lot of ocean water. Get it moving (because the Moon and the Sun move, and the Earth rotates under them, and there’s a whole lot of ocean currents on top of that, due to differences in water temperatures and salinity, and coriolis forces, and whatnot) and it builds up a lot of inertia.

    Push it into geography that keeps narrowing and narrowing like a funnel, and the only place it can go is in, and up.

    Water gets in there, wants to get out, but there’s a whole damn ocean pushing it in, so it has no option but to keep accumulating into the funnel.

    Also, having the geography look a bit like a Tesla valve that’ll easily let water in but not so easily let it out probably doesn’t help either; place’s bound to get close to overflowing, before it can empty itself out.

    Image

    source