Thisis one more attempt at explaining the nature of the Earth’s magneticfield. The presumption is that a deepplume moving slowly will twist and distort the magnetic field.
Howsuch movements may be produced in the high pressure and heat of the deep mantleescapes me or even to describe a motive force that would not be reflected inmassive surface movements which are clearly missing.
Besidesa mapping of the Earth’s magnetic field fails to conform to the implied internalgeometry. We instead get a clear lack ofsymmetry and shifts back and forth over the Earth’s surface.
Ihave made the conjecture of a thin layer at the appropriate transition zonearound a hundred miles deep at least and plausibly much deeper consisting of ahundred meters or more of molten carbon having a near zero viscosity. This is particularly evidenced by diamondpipes that rocket to the surface at close to seventy miles per hour accordingto sources.
Sucha layer provides a guide for powerful electron flows able to produce thenecessary magnetic fields that we encounter. It also provides for the necessary mobility we also observe in the timeframes presented. Just as obviously, sucha layer easily allows pole reversal already known but not explained in any waythat is not nonsense.
Thelevel of movement presently observed is also confirmed in the geologicalrecord. It is our good fortune to see itsped up.
Why is the north magnetic pole racing toward Siberia ?
By John Matson | Dec 24, 2010
Finding Santa Claus's home at the North Pole is easyon a globe—just look for the point on top where all the lines of longitudemeet. But that is just the "geographic" North Pole; there are several other definitions for the poles,all useful in different scientific or navigational contexts. Among the manynorth poles, let us rejoice that Santa Claus did not choose the magnetic polefor his home, for he would have to spend as much time moving as deliveringpresents.
The north magnetic pole (NMP), also known as the dip pole, is the point onEarth where the planet's magnetic field points straight down into the ground.Scottish explorer James Clark Ross first located the NMP in 1831 on the BoothiaPeninsula in what is now northern
But the NMP drifts from year to year as geophysical processes within Earthchange. For more than 150 years after Ross's measurement its movement wasgradual, generally less than 15 kilometers per year. But then, in the 1990s, itpicked up speed in a big way, bolting north–northwest into the
One compelling explanation appears in the December 21 Eos, theweekly transactions of the American Geophysical Union. In their Eos article(subscription required), and in alonger paper published earlier in 2010 in the Journalof Geophysical Research–Solid Earth, ArnaudChulliat of the Institute of Earth Physics of Paris and hiscolleagues venture that a twisting molten plume beneath the Artic could be thecause:
Accordingto some recent models, plumes of less dense fluid form at the inner coreboundary and subsequently rise within [a cylinder] whose central axis is theEarth’s rotation axis. Such plumes undergo a strong helical motion due to theEarth’s rapid rotation, a phenomenon also observed in laboratory experimentswith water. In the core, helical plumes advect and twist the magnetic fieldlines, forming what scientists call "polar magnetic upwellings."
Those upwellings, unloaded into the Arcticmantle, could produce intense patches of magnetic activity on the sort ofdecade-long timescales needed to explain the NMP's sudden acceleration. (Theauthors compare these patches to a kind of terrestrial version of sunspots.)And magnetic field measurements show dramatic shifts near the New Siberian Islands that seem to fit the bill.
"What happened under the New Siberian Islands at the core surface is that the rateof change of the magnetic field changed by a large amount during the1990s," Chulliat says. That activity, he and his colleagues have found,could account for a large portion of the NMP's acceleration. But whethermagnetic field changes under the New Siberian Islands and the speeding north magnetic pole ultimately arise from a twisted plume offluid rising through the core remains unproved, Chulliat and his co-authorsnote. A resolution of the mystery will await better modeling, along with moredata from satellites monitoring the Arctic 'smagnetic environment. The necessity of satellites, interestingly enough, is aconsequence of the pole's recent movement—as the NMP drifts farther out to sea,it becomes harder and harder to reach the region with magnetometer-equippedaircraft.
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