Has the Earth’s Magnetic Core Stopped Rotating? By Brian Simpson
It has been said that science scares people; and it does indeed. Consider; the claim made by scientists recently that the Earth’s magnetic core has stopped rotating, and could reverse itself. The claim is based upon research published in the top-ranking journal Nature Geoscience. There is apparently a hot debate about what this means in the geoscience community, which for such a radical claim is natural enough. We don’t go into the science here, but the human significance of such events. Some internet sites are predicting a magnetic disaster, with dire effects upon animals, due to effects upon the Earth’s magnetic field, and our protection against cosmic radiation. That sounds plausible, only thing is, there is an argument that the core does not produce a magnetic field at all, and may not be moving in the first place. For those interested, there is material by a dissent geologist below. We will simply have to wait and see how this one goes, because there is absolutely nothing you and I can do to influence the Earth’s core, that’s for sure!
Former Geologist and Professor Sep 26
Earth's “core” doesn't produce any magnetic field at all. The Earth's deep interior still holds many mysteries that scientists are trying to unravel. The Earth’s core and its alleged composition are hypothetical constructs, NOT facts. The proposed mineral models for the inner core have always shown a faster wave speed than that observed in seismic data. This mismatch has given rise to several complex “theories” about the state and evolution of the Earth's core. Therefore, the unobservable processes in the alleged liquid iron core, where the magnetic field is apparently generated by a hydromagnetic dynamo are baseless. However, dynamo theories still attempt to explain planetary magnetic fields positing metal-rich molten material, swirling round and round deep inside a planet.
The only possibility of having a dynamo in the Earth's core requires motion of fluid in the core of the Earth; that such motion cannot be a simple rotation, or any other symmetric motion; and that all proposed motions have been unreasonably complex motions. Bear in mind that a manmade dynamo is carefully constructed to create electrical currents as efficiently as possible; the “naturally” occurring dynamo in the Earth operates in an almost spherical body of nearly homogeneous electrical conductor, where short-circuiting of electrical currents is severe. The very different character of man-made and naturally occurring dynamos became apparent in 1933, when Cowling published his famous theorem, that a dynamo cannot maintain an axisymmetric magnetic field, like Earth does.
As of now there is no physical evidence, seismic or otherwise, that there is any motion within the core. Also, numerical modelling of the self sustaining “dynamo,” that allegedly generates Earth's magnetic field, has not been successfully demonstrated. Two geoscientists who try to simulate dynamo action in the Earth with supercomputers summarized the generalized results of "Cowling's theorem" very simply (Roberts and Glatzmaier, 2000, their italics): “…an axisymmetric B [magnetic field] cannot be sustained by dynamo action”. Dynamo theory has fared poorly in the Solar system, particularly with the strong former fields of the Moon and Mars, and the presently fast-decaying field of Mercury. It cannot account the phenomenon of field polarity reversals.
The magnetic field on Earth is originated by its rotation, as a whole body around the polar axis. In fact, the observed correlation of the angular momenta L and magnetic moments μ of celestial bodies (the Sun, planets and stars) have been discussed by several authors. Recent observations show that the
correlation exists for planets and for other celestial bodies. This offers a clue of the origin of magnetic fields in rotating celestial bodies, including Earth. However, this finding as been ignored by the mainstream geoscientist community. If Earth as a whole stops spinning, no magnetic field would exist and therefore, no life could survive. Without the Earth’s magnetic field (magnetosphere), the stream of energetic charged particles emanating from the Sun, could strip the Earth of its protective layers, which shield us from the Sun’s ultraviolet radiation, harmful to lifeforms.
After nearly a century of hard work, scientists have failed to prove that a dynamo is actually working, or even could work in the Earth's core today. Analytic theory, numerical simulations, laboratory experiments, and planetary observations all weigh against it.”
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