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Earth Science

Earth's Magnetic Field Is Acting Up and Geologists Don't Know Why (nature.com) 192

Posted by EditorDavid from the bi-polar-disorder dept.
schwit1 quotes Nature: Something strange is going on at the top of the world. Earth's north magnetic pole has been skittering away from Canada and towards Siberia, driven by liquid iron sloshing within the planet's core. The magnetic pole is moving so quickly that it has forced the world's geomagnetism experts into a rare move. [T]hey are set to update the World Magnetic Model, which describes the planet's magnetic field and underlies all modern navigation, from the systems that steer ships at sea to Google Maps on smartphones. The most recent version of the model came out in 2015 and was supposed to last until 2020 -- but the magnetic field is changing so rapidly that researchers have to fix the model now.

"The error is increasing all the time," says Arnaud Chulliat, a geomagnetist at the University of Colorado Boulder and the National Oceanic and Atmospheric Administration's (NOAA's) National Centers for Environmental Information.... By early 2018, the World Magnetic Model was in trouble. Researchers from NOAA and the British Geological Survey in Edinburgh had been doing their annual check of how well the model was capturing all the variations in Earth's magnetic field. They realized that it was so inaccurate that it was about to exceed the acceptable limit for navigational errors.
Nature's article was updated on January 9th to inform readers that the release of the corrected World Magnetic Model, which should restore accuracy through the end of 2019, has now been postponed from January 15th to January 30th -- "due to the ongoing US government shutdown."
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Earth's Magnetic Field Is Acting Up and Geologists Don't Know Why More

Earth's Magnetic Field Is Acting Up and Geologists Don't Know Why

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  • Time, tide, and the magnetic north pole wait for no man.

  • Declination is not news (Score:5, Informative)

    by Anonymous Coward on Sunday January 13, 2019 @04:47AM (#57953292)

    Declination needs to be changed every year by serious navigators. More often near the poles. This has been true since before any slashdot reader was born.

    The magnetic shift is increasing in complexity and rate of change. This has also been known for a very long time.

    We are overdue for a pole shift given our current understanding of the magnetosphere. We might be lucky enough to witness multiple north and south poles, followed by a rapid reversal where every magnetic compass in the world will point the wrong way.

    • Declination needs to be changed every year by serious navigators.

      Serious navigators use GPS, which is a gazillion times more accurate than figuring out where you are with a compass and sextant.

      • Re:Declination is not news (Score:4, Interesting)

        by repepo ( 1098227 ) on Sunday January 13, 2019 @06:48AM (#57953494)
        Airplane pilots still use magnetic headings to identify runways which is gazillion times simpler than using GPS (doesn't even require power). Runways are numbered according to their orientation relative to the horizontal magnetic field (their declination). The wandering of the North pole is however inconvenient as these runway numbers must be changed accordingly every now and then.

      • Comment removed (Score:5, Insightful)

        by account_deleted ( 4530225 ) on Sunday January 13, 2019 @07:27AM (#57953560)
        Comment removed based on user account deletion

        • Couldn't have said it better. Instruments fail all the time. Knowing how to navigate by first principles is needed if one is to survive. Besides which, situations are unpredictable. Your ship may sink, or your aircraft may crash in the middle of nowhere, and take your navigational automation with it.

      • Serious navigators use GPS, which is a gazillion times more accurate than figuring out where you are with a compass and sextant.

        Serious navigators have multiple ways of figuring out where they are. https://chuckhillscgblog.net/2... [chuckhillscgblog.net]

        GPS is convenient and easy to use. But a delicate thing, prone to jamming.

        They do have a nickname for people who rely solely on GPS. Lost.

      • Re: (Score:2)

        by Anonymous Coward

        Serious navigators use GPS, which is a gazillion times more accurate than figuring out where you are with a compass and sextant.

        Lord, was that ever a millennial statement if there ever was one. Serious navigators aren't stupid enough to rely on technology that they don't control and don't understand without working knowledge of other ways of navigating, whether they choose to use GPS or not.

        Over reliance on GPS has and will cost lives--in small numbers to date to be sure, but mass casualties will occur if (when) the system suffers a failure or is caused to suffer a failure. Only the stupid and corporate bean counters think that re

      • Re:Declination is not news (Score:5, Interesting)

        by Solandri ( 704621 ) on Sunday January 13, 2019 @01:31PM (#57954706)

        Serious navigators use GPS, which is a gazillion times more accurate than figuring out where you are with a compass and sextant.

        The Earth's magnetic field deflects charged particles from the sun, sending them to the polar regions where they become the aurora when they hit the atmosphere. This creates a low-radiation bubble [wikipedia.org] up to a certain altitude above the Earth. GPS satellites orbit in between the two major belts where radiation is deflected.

        A pole flip may be associated with a weakening magnetic field for a short time during the flip. In which case those charged particles will not be deflected towards the poles. They will strike all the satellites that were formerly protected, like GPS satellites. Those satellites have some radiation hardening to survive the occasional solar flare, but probably would not survive something this intense for too long.

        • Those satellites have some radiation hardening to survive the occasional solar flare, but probably would not survive something this intense for too long.

          I'm less concerned about the satellites surviving; a little more concerned about life on the surface.

      • To use GPS you need to have sight of the sky. That may be the case in your navigational tasks. For mine (surveying newly-discovered caves tens of kilometres from daylight as the cave-cricket walks and up to a kilometre below the land surface, it's not true.)

        The penetration of RF signals into rock with more than a few % of water is measured in tens of metres at most

        • Re: (Score:3)

          by dryeo ( 100693 )

          Curious, how well do magnetic compasses work down there? Or what do you use. String seems a good idea, at least to find your way back.

      • Re: (Score:2)

        by dryeo ( 100693 )

        Serious navigators don't depend on one system, especially one that depends on electronics and batteries. Compass works fine when wet, so does the sextant,

    • Re:Declination is not news (Score:5, Funny)

      by Z00L00K ( 682162 ) on Sunday January 13, 2019 @05:23AM (#57953356) Homepage Journal

      The inside of the Earth is liquid and not homogeneous so things changes quite a bit over time.

      I wonder if a polarity change will coincide with eruption of Yellowstone. And I worry more about an eruption than a polarity change.

    • "We might be lucky enough to witness multiple north and south poles, followed by a rapid reversal where every magnetic compass in the world will point the wrong way."

      Or it might not be rapid. In which case, the real fun happens.

      • Re:Declination is not news (Score:5, Informative)

        by iggymanz ( 596061 ) on Sunday January 13, 2019 @12:03PM (#57954302)

        You might have read alarmist articles on the matter.

        The serious science is this:

        reversals are rapid

        the magnetic field does not disappear during reversals though there may be multiple poles

        no extinctions correlate with them

        the solar wind interacting with the upper atmosphere would protect us from cosmic rays

        so the "fun" would be technology / navigational system issues, no anything directly dire to life

        https://arxiv.org/abs/astro-ph... [arxiv.org]

        • Re:Declination is not news (Score:4, Informative)

          by RockDoctor ( 15477 ) on Sunday January 13, 2019 @07:17PM (#57956240) Journal
          reversals are rapid Define "rapid." There's at least one sill (intrusion parallel to country rock lamination) which solidified during a reversal. The event was too rapid to "see" through direct radiometric dating, but by measuring the melting temperature of the rock (the texture indicates that it was emplaced fairly fluid), the Curie temperature and with how well the surrounding rocks conduct heat, the cooling time of the sill is estimated as taking several centuries. And the orientation of the magnetic field changed by about 150 degrees during those centuries.

          But yeah, "rapid" for certain meanings of "rapid".

          the magnetic field does not disappear during reversals though there may be multiple poles That is how the models go - and it is not incompatible with the observations noted above. They're well supported models, but not observations.

          no extinctions correlate with them

          No more than would be expected by chance. No fewer, either.

          so the "fun" would be technology / navigational system issues, no anything directly dire to life

          Yep, I'd look forward to living through one, particularly since that would imply a lifetime of several centuries.

          • might be several centuries of popped and popping power transformers and supplies, lousy radio reception, useless compass and Hall effect navigation, northern lights in non-northern places....

          • Well to be fair a couple of centuries is very rapid in relation to geologic time...

            I was thinking of that myself really though as to what that change might actually look like to an actual observer. When it is described it is usually talking about "flipping" which sounds pretty instantaneous. Which a couple hundred years is in relation to billions of years, or at least hundreds of millions. Though in looking it up it seems to "flip" at least several times more less per million years or so... Still talking se

      • They'll all point backwards, which means the ones in Australia will finally point right!

    • Its unpredictable motion is news (Score:2, Informative)

      by Anonymous Coward

      The fact that the magnetic field is moving is not news. The problem is that it's moving unpredictably.

      The two major geomegnetic field models (the World Magnetic Model [wikipedia.org] and the International Geomagnetic Reference Field [wikipedia.org]) have long included time-varying terms. These predict the magnetic field shape (to about 10th order spherical harmonics, not just the pole location!) for the five years between releases.

      Both released a model in 2015, which was expected to be good until the next release in 2020. But the field

    • True, this isn't news, geologists have known about this for a long time now, and yes a pole flip is theoretically overdue.
      What I'm more concerned about is the strength of the magnetic field, since that's what's protecting us from solar radiation. Theoretically during a pole flip the field strength will drop to zero for a period of time. Who knows what sort of chaos that'll cause.

    • Except the rate of change is remarkable in the modern era - 2 deg latitude from 1900-1920, and 10 deg of latitude the last 10 years.

      One might well observe that sort of acceleration pretty much parallels the accelerating warming instrumentally observed over the 20th century as well. If you change the orientation of the magnetosphere to the surface of the earth and the ecliptic by 20deg over a century, one might also suspect that changing orientation would have pretty significant effects on the solar-driven

  • It's Putin! (Score:1, Offtopic)

    by h33t l4x0r ( 4107715 )
    It's a diabolical plan to move the North Pole to Russia so he can steal all those toys! And Trump is in on it!

  • "Acting up" - as if there's something wrong, when it's simply something that we don't understand. Following a few links, the mass media is already adding even more adjectives, like "going haywire", to make it sound like looming disaster. I'm sure some "science journalist" will now take this out of context and blame it on global warming, or Trump, or whatever...

    Meanwhile, the magnetic pole is getting closer to the cartographic pole, which seems like a good thing overall...

    • Re: (Score:1)

      by Anonymous Coward

      Meanwhile, the magnetic pole is getting closer to the cartographic pole, which seems like a good thing overall...

      I spy with my third eye a Wilbur Whateley who's been keeping up with the old 'incanting of the Dho formula' shtick...

  • Nibiru or PlanetX (Score:1)

    by Anonymous Coward

    It's because Nibiru aka PlanetX is nearing. Same thing happened the last time it passed by and it caused the great flood (the Noah's ark one).

    Apparently that's why all the world's leaders are visiting Antarctica. Because you can see the planet incoming from there using a telescope.

    https://solarsystem.nasa.gov/planets/hypothetical-planet-x/in-depth/

  • In other news... (Score:1)

    by Anonymous Coward

    Gravity is Worryingly Holding Things Together and Physicists Don't Know Why.

    Life Happened and Biologists Don't Know Why.

    Uranus is Strangely Dark and Astronomers are Left Holding Their Nose!

    The geomagnetic field is dynamic, always has been. Geologists and Geophysicists are interested but not worried. Seismologist do, however, get worried every time the title's author's mother gets out of bed in the morning.

    • Re: (Score:1)

      by Anonymous Coward

      Uranus is Strangely Dark and Astronomers are Left Holding Their Nose!

      For God's sake. Put away the smelloscope.

  • US Gov got shut down, so magnetic field is failing, like those SSL certs... soon the earth will implode.

    • It's tongue-in-cheek, but the parent comment is the "it's Trump's fault" comment some of you are looking for.

  • The change in the magnetic north pole, is also the reason you'll see airports repaint their runway markers from time to time.
  • The liquid iron theory is so old and so dumb, why is it always repeated? Curie temperature, you know about it?

  • From what I know the Earth magnetic field reverses it's poles regularly [wikipedia.org] (in geological scale) and all signs indicate it is happening now. The process takes quite long in human life scale and the intermediate state goes through many poles magnetic field, a weak one and even no magnetic field.

    It's not a new news, the magnetic anomalies have been observed for a while and it will have impact on our lives, and I hope that more and more elected politicians will be either scientific savvy, or at least will apprec

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