"We are witnessing a true reversal of ocean circulation in the Southern Hemisphere—something we’ve never seen before,” explains Antonio Turiel, ICM-CSIC researcher and co-author of the study. “While the world is debating the potential collapse of the AMOC in the North Atlantic, we’re seeing that the SMOC is not just weakening, but has reversed. This could have unprecedented global climate impacts.”

  • Bob Robertson IX @discuss.tchncs.de
    link
    fedilink
    English
    arrow-up
    5
    ·
    1 day ago

    I had to look up that last part, as it seemed counter-intuitive, but apparently deep ocean water bottoms out at 4 degrees C.

    Right, but I still wouldn’t call water that is 4 degrees C as warm. How is deep water warm?

    • wjrii@lemmy.world
      link
      fedilink
      English
      arrow-up
      4
      ·
      20 hours ago

      I’m not going to claim to fully understand the nuances, but the sea ice will melt at about -2C and glacial melt will deposit ~1C water into the system. If the deep water is steady at 3C or 4C, sending it up could accelerate melting of both.

      • Bob Robertson IX @discuss.tchncs.de
        link
        fedilink
        English
        arrow-up
        3
        ·
        17 hours ago

        Thank you… I’m an idiot and wasn’t thinking about the Southern Ocean as in ‘The’ Southern Ocean… instead I was thinking about it in terms of the oceans in the south (as in, not necessarily glacial). But yes, now I get it and understand. It probably would have helped if I had opened the link to start with.

    • WanderingThoughts@europe.pub
      link
      fedilink
      English
      arrow-up
      9
      ·
      1 day ago

      That was my physics teacher.

      “So materials shrink as they get colder.”

      “Ma’am, doesn’t ice expand?”

      “We don’t talk about that.”

      • dubyakay@lemmy.ca
        link
        fedilink
        English
        arrow-up
        3
        ·
        19 hours ago

        Ice doesn’t expand. Ice as a solid shrinks when getting colder. H2O expands during phase transformation from liquid to solid.

        • Natanael@infosec.pub
          link
          fedilink
          English
          arrow-up
          2
          ·
          17 hours ago

          The density of ice Ih increases when cooled, down to about −211 °C (62 K; −348 °F); below that temperature, the ice expands again (negative thermal expansion).