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Earth Science

As Magnetic North Pole Zooms Toward Siberia, Scientists Update World Magnetic Model (npr.org) 161

Posted by BeauHD from the always-on-the-move dept.
An anonymous reader quotes a report from NPR: Earth's geographic north pole is fixed. But the planet's magnetic north pole -- the north that your compass points toward -- wanders in the direction of Siberia at a rate of more than 34 miles per year. That movement may seem slow, but it has forced scientists to update their model of Earth's magnetic field a year earlier than expected so that navigational services, including map-based phone apps, continue to work accurately. The drift results from processes taking place at the center of the planet. Molten iron and nickel slosh and spin in the planet's core, essentially serving as a metallic conductor for Earth's magnetic field. Changes in that fluid flow lead to changes in the magnetic field. As a result of those changes, the accuracy of the National Oceanic and Atmospheric Administration's World Magnetic Model (WMM) -- a mathematical representation of the magnetic field -- slowly deteriorates in the five-year periods between updates. The next update was due in 2020. But "unplanned variations" have degraded the quality of the WMM so greatly that NOAA published an out-of-cycle update Monday. It was delayed from January by the partial government shutdown.
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As Magnetic North Pole Zooms Toward Siberia, Scientists Update World Magnetic Model More

As Magnetic North Pole Zooms Toward Siberia, Scientists Update World Magnetic Model

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  • geographic north pole is not fixed either (Score:5, Interesting)

    by iggymanz ( 596061 ) on Tuesday February 05, 2019 @10:35PM (#58076932)

    spin axis of earth drifts too, about 10 cm a year, caused by events that redistribute the earth's mass.

    • spin axis of earth drifts too, about 10 cm a year, caused by events that redistribute the earth's mass.

      Interesting - never heard of it.

      Do you mean Polar motion [wikipedia.org] as one of the Earth's rotation axis distortions [wikipedia.org] (others being precession [wikipedia.org] and nutation [wikipedia.org])?

  • Is these changes in earth magnetic field associated with Tsunami or other major natural calamities ?

    • Is these changes in earth magnetic field associated with Tsunami or other major natural calamities ?

      No its associated with changes in flow of the molten metal at the core. rtfs.

      The drift results from processes taking place at the center of the planet. Molten iron and nickel slosh and spin in the planet's core, essentially serving as a metallic conductor for Earth's magnetic field. Changes in that fluid flow lead to changes in the magnetic field.

  • How many degrees off of true north is it when the poles reverse or at what rate of change? Has that even been determined using the Atlantic rock layers? If not, it could be good to know.

    • Re: (Score:2)

      by Mashiki ( 184564 )

      Off true north? There's nothing beyond guesses. But before reversals the poles have moved as much as 6deg/day.

    • I suspect pole reversals are a consequence of the rotational axis of the Earth's core not being perfectly aligned with the minimum or maximum moments of inertia. When you spin an object around a different axis that the minimum or maximum moments of inertia, it tumbles - the rotational axis is not fixed, and drifts almost chaotically. Occasionally it will suddenly flip [youtube.com].

      If correct, pole reversals are going to be unpredictable unless you can exactly measure the inertia tensor of the Earth's core and its ro

  • DAMN RUSSIANS! (Score:5, Funny)

    by LynnwoodRooster ( 966895 ) on Wednesday February 06, 2019 @05:26AM (#58077646) Journal
    First they steal Ukraine. Then they steal our election. Now they steal the North Pole!
  • The South Magnetic Pole is already close to Vostok station in Antarctica.
  • but Putin is doing this - he waves his dick. This does not cause much besides wave of hysteria in msm - this in turn has a mass and causes many disturbances - some cannot sleep, some lose their cool and have sex w/o protection and some others exit EU or vote Trump into office. The amount of heat caused by waving the dick itself is also minimal but the amount of heat generated by over excited journalists may cause serious damage to our planet. Therefore I think we will have to remove: Putin, Trump and all th

  • Climate (Score:3)

    by argStyopa ( 232550 ) on Wednesday February 06, 2019 @10:21AM (#58078514) Journal

    Here's a question: as the earth's magnetic field is based significantly on the location of the magnetic pole, the strength of any electromagnetic field varies significantly depending on the incidence angle of incoming particles (ie to exclude solar wind) has anyone studied what impact this shift would have on earth's climate?

    Looking at http://wdc.kugi.kyoto-u.ac.jp/... [kyoto-u.ac.jp] the pole has shifted 5x the distance recently as at the start of the last century. Does the northward shift of the magnetic field by 16-17 degrees with increasing speed track at all with increasing surface temps?

    • Here's a question: as the earth's magnetic field is based significantly on the location of the magnetic pole, the strength of any electromagnetic field varies significantly depending on the incidence angle of incoming particles (ie to exclude solar wind) has anyone studied what impact this shift would have on earth's climate?

      Yes.

      Danish astrophysicist Henrik Svensmark and Danish geophysicists Mads Knudsen and Peter Riisager say those shifts in the magnetic field that allow more charged particles to enter the atmosphere affect cloud formation in the upper atmosphere. They say the current alignment has been reducing cloud formation and precipitation at lower latitudes for the last hundred years, increasing temperatures.

      Knudsen, Mads F. and Peter Riisager. "Is there a link between Earth’s magnetic field and low-latitude prec [doi.org]

      • Ouch, that sort of conclusion would be enough to get you kicked out of, well, everything.

        Thanks for the link.

  • I thought GPS used satellites, and smartphones used both GPS and cell towers, not magnetic north. WTF is all that bullshit?

    • Have you ever noticed your phone can show your orientation on a map if you stand perfectly still and turn in a circle? That's not GPS. That's just a magnetic compass at work.

    • You would think so, but it's both, my phone one app points to magnetic north and is telling me that the magnetic field strength is 49.5 T, another can switch between magnetic, network or GPS direction.

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