This
is one more attempt at explaining the nature of the Earth’s magnetic
field. The presumption is that a deep
plume moving slowly will twist and distort the magnetic field.
How
such movements may be produced in the high pressure and heat of the deep mantle
escapes me or even to describe a motive force that would not be reflected in
massive surface movements which are clearly missing.
Besides
a mapping of the Earth’s magnetic field fails to conform to the implied internal
geometry. We instead get a clear lack of
symmetry and shifts back and forth over the Earth’s surface.
I
have made the conjecture of a thin layer at the appropriate transition zone
around a hundred miles deep at least and plausibly much deeper consisting of a
hundred meters or more of molten carbon having a near zero viscosity. This is particularly evidenced by diamond
pipes that rocket to the surface at close to seventy miles per hour according
to sources.
Such
a layer provides a guide for powerful electron flows able to produce the
necessary magnetic fields that we encounter.
It also provides for the necessary mobility we also observe in the time
frames presented. Just as obviously, such
a layer easily allows pole reversal already known but not explained in any way
that is not nonsense.
The
level of movement presently observed is also confirmed in the geological
record. It is our good fortune to see it
sped 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 easy
on a globe—just look for the point on top where all the lines of longitude
meet. 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 many
north poles, let us rejoice that Santa Claus did not choose the magnetic pole
for his home, for he would have to spend as much time moving as delivering
presents.
The north magnetic pole (NMP), also known as the dip pole, is the point on Earth 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 Boothia Peninsula in what is now northern
But the NMP drifts from year to year as geophysical processes within Earth change. For more than 150 years after Ross's measurement its movement was gradual, generally less than 15 kilometers per year. But then, in the 1990s, it picked up speed in a big way, bolting north–northwest into the
One compelling explanation appears in the December 21 Eos, the weekly transactions of the American Geophysical Union. In their Eos article (subscription required), and in a longer paper published earlier in 2010 in the Journal of Geophysical Research–Solid Earth, Arnaud Chulliat of the Institute of Earth Physics of Paris and his colleagues venture that a twisting molten plume beneath the Artic could be the cause:
According
to some recent models, plumes of less dense fluid form at the inner core
boundary and subsequently rise within [a cylinder] whose central axis is the
Earth’s rotation axis. Such plumes undergo a strong helical motion due to the
Earth’s rapid rotation, a phenomenon also observed in laboratory experiments
with water. In the core, helical plumes advect and twist the magnetic field
lines, forming what scientists call "polar magnetic upwellings."
Those upwellings, unloaded into the Arctic
mantle, could produce intense patches of magnetic activity on the sort of
decade-long timescales needed to explain the NMP's sudden acceleration. (The
authors 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 rate
of change of the magnetic field changed by a large amount during the
1990s," Chulliat says. That activity, he and his colleagues have found,
could account for a large portion of the NMP's acceleration. But whether
magnetic field changes under the New Siberian Islands
and the speeding north magnetic pole ultimately arise from a twisted plume of
fluid rising through the core remains unproved, Chulliat and his co-authors
note. A resolution of the mystery will await better modeling, along with more
data from satellites monitoring the Arctic 's
magnetic environment. The necessity of satellites, interestingly enough, is a
consequence 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-equipped
aircraft.
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