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The 40,000-Mile Volcano ( 85

An anonymous reader writes: The NY Times reports on one of the wonders of the underwater world: the extensive web of volcanoes and hydrothermal vents present where tectonic plates meet and grind against one another. "Welcome to one of the planet's most obscure but important features, known rather prosaically as the midocean ridges. Though long enough to circle the moon more than six times, they receive little notice because they lie hidden in pitch darkness." The magma seeping through these cracks generate massive amounts of heat — enough to sustain incredible ecosystems.

But as scientists have gained a deeper understanding of this geological phenomenon, they realize it's more chaotic than they had imagined. "The old idea was that the eruptions of oozing lava and related activity occurred at fairly steady rates. Now, studies hint at the existence of outbursts large enough to influence not only the character of the global sea but the planet's temperature. Experts believe the activity may carry major repercussions because the oceanic ridges account for some 70 percent of the planet's volcanic eruptions. By definition, that makes them enormous sources of heat and exotic minerals as well as such everyday gases as carbon dioxide, which all volcanoes emit."

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The 40,000-Mile Volcano

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  • when the volcano blows, Mr. Utley.
  • By definition, that makes them enormous sources of heat

    Well how much heat? TFA doesn't say. Enough to pilot El Nino or something similar? More?

    • El nino influences the pacific. THe mid ridge which moves the continents apart is in the Atlantic which since Pangia has moved Europe, Africa, and the Americas apart about 2 inches a year

      • The ridges they are talking about (there's a nice map in the article) go through every ocean on the globe.
  • Could that mean its not cow farts causing global warming?
  • by phantomfive ( 622387 ) on Tuesday January 12, 2016 @07:52PM (#51290721) Journal
    The summary makes it seem like it's an issue about global warming, but it's really not - the article briefly touches on that point. The exciting thing here is that scientists have spent years building up a new sensor network, monitoring the underwater ridges. Now, the network is about to go live, and they are about to get tons of data. Before that, they mainly were able to investigate by dropping expensive subs down there (and by using data from the Navy's submarine detectors).

    Also, check out this picture []. If there is anything related to AGW, it's probably just a little nudge to open the door to more funding.
    • The summary is designed to generate page hits and replies.
    • Re:Not about AGW (Score:5, Informative)

      by Rei ( 128717 ) on Tuesday January 12, 2016 @08:14PM (#51290809) Homepage

      Note that "midoceanic ridges" doesn't entirely mean "underwater ridges". I happen to live in a place where the ridge breaks the surface - by several kilometers in places. You can investigate the mid-Atlantic ridge (at least a small part of it) right here on the surface, no subs needed. You can also check out part of the ridge in freshwater [].

      One of the common misconceptions is that there's a single fissure that makes up the "ridge". The reality is that there's a whole chain of meandering but largely parallel grabens (sharp-sided tectonic valleys), fissure-volcanic ridges, and individual volcanoes. It doesn't always break at the same place, it breaks over dozens to hundreds of kilometers on either side of the "average" centerline of the ridge. Also, the volcanism can be quite diverse. Here we have everything from basalt to rhyolite, deep-sourced and shallow-sourced magma, gas-rich and gas-poor magmas, widely varying levels of sulfur and fluorine emissions, etc.

      • I appreciate the pictures, but I think you'd have to be somewhat insane to go swimming in the frigid waters of Iceland.
        • Re:Not about AGW (Score:5, Interesting)

          by Rei ( 128717 ) on Tuesday January 12, 2016 @09:10PM (#51291037) Homepage

          It's drysuit diving. It would be stupid to do it any other way. ;)

          There was a guy that on a dare from his family jumped into one of those flooded rift canyons last year, naked. He had no clue what water that cold does to your body, he's lucky he didn't drown. He quickly lost all energy, and combined with there being no easy way out was stuck half in the the water trying to get out, unable to climb any further. He was lucky that the rescue services got to him in time.

          FIle that under "stupid things tourists do", along with "go hiking alone on a glacier with no prior experience and without telling anyone" and "walking up to the edge of a mud pot, not giving half a thought to the fact that they're standing at the edge of a boiling cauldron of liquid water that's actively eroding the clay around it." There's never any shortage of people to rescue. There's one team that's been hiking across Iceland this winter that's already had to be rescued three times ;)

          • along with "go hiking alone on a glacier with no prior experience and without telling anyone"

            ok, that one actually sounds kind of fun, though

            • by Rei ( 128717 )

              If dying in a crevase is your idea of fun, then go right ahead ;)

              Okay, to be fair, the flat-topped ice sheets are generally pretty safe. It's where the ice flows over contours and descends into the lowlands that they get dangerous, what we call a skriðjökull. They end up looking [] like [] this []. And oftentimes these crevases form beneath before they become visible [] on the surface. The glaciers can also be (surprise surprise) very slippery [] at times.

              Sometimes idiots actually try to drive passenger cars

            • by Rei ( 128717 )

              Oh, and don't be anywhere near the flat tops when there's volcanic activity going on, because they often overlay volcanoes. And when there's even a small "burp" of heat, you get what's called a sigketill [] forming, and that would be very bad news for you ;) And in case those little "ripples" on the edge of the bowl-shaped ones (as opposed to the "sheer drop" ones and the "boiling lake" ones) don't look so bad, here's what they look like close up []. Think video game-style bottomless pits. Into a volcano. ;)

              • ok, that all looks really exciting.
                People have crossed Greenland, though (I assume it has similar problems), and did it a long time ago before GPS. How do you do it to get across safely?
                • by Rei ( 128717 )

                  For the stuff on the ice caps, glacier tour guides run professional operations where they keep track of every rift as it forms and relay the information to each other. For the more dangerous stuff like on a skriðjökul, there's some of that as well, but also in general it takes about extreme care, constantly testing the ground in front of you, and being tethered to each other to help arrest unexpected falls, among other things. And even then it can still be dangerous.

                  Ironically, though, sometimes

                • People have crossed Greenland, though (I assume it has similar problems)

                  Greenland is a hell of a lot less volcanically active than iceland.

          • by KGIII ( 973947 )

            I have no idea why they do that, tourists that is. We lose a few every year. We go out and rescue them every year. We said we were going to start charging them but we haven't. I go out with them every year. I have attended lots of training classes and kept up with it so I go. We have them go through the ice every year. We end up having to wait until spring before we can recover the body - every year. Sometimes we don't get to recover that in a timely fashion and they make it all the way to the ocean, someti

    • by KGIII ( 973947 )

      Thanks. It's a bit costly for a coffee table book but I ordered a copy. It has pictures so I can look at it and fool people into thinking I'm learning.

Each honest calling, each walk of life, has its own elite, its own aristocracy based on excellence of performance. -- James Bryant Conant