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Earth's Magnetic Anomalies -
Could the Poles Flip?
by Linda Moulton Howe
April 27, 2002 Cambridge, Massachusetts - Deep beneath our feet as we walk around in fact, 4,000 miles down is the center of the earth where an iron core is so hot it is liquid and boils around like cooking porridge. That moving, melted iron also produces the magnetic fields that surround the earth and upon which much of earth's surface life, satellites and space technology depend upon for orientation, and for protection. If magnetic fields did not trap highly energetic particles racing from the sun, all kinds of damage could be done to living organisms and space technologies. For nearly a million years, magnetic field lines have been coming out of the south pole and entering the north pole of the earth. That is called the magnetic dipole.
Now a science team from Paris, France led by Gauthier Hulot at the Institute of Earth Sciences in Paris - working with other scientists such as Harvard University's magnetic field expert, Dr. Jeremy Bloxham - have compared satellite measurements of the earth's magnetic field strengths 25 years ago and today. Their discovery was published in the April 2002 science journal Nature and it boils down to this: there are strange and not very well understood variations now in the earth's magnetic field. In fact, down in South Africa there is a large region that already has a magnetic field pointing in the opposite direction from the rest of the earth's field and is getting stronger all the time, according to new satellite data.
Further, the north and south pole magnetic fields have weakened in strength by about 10% of what they were. If the South African region continues to get stronger and the poles keep weakening, scientists think that within the next millennia, the pole magnetic fields could disappear altogether, or flip so the magnetic field lines would leave the north pole and enter the south pole. Meanwhile, could magnetic field anomalies and changes in strengths and geographical locations persist during a transition period to an unknown outcome?
Based on ancient rock studies, geophysicists can say that such a situation happens three or four times every million years. There can even be a period when there are many magnetic poles all over the planet, not just at the poles. But no one knows for certain what the implications are for earth life and technology because it hasn't happened since 780,000 years ago.
Recently, I talked with Dr. Bloxham's graduate assistant, Mathieu Dumberry from Canada, who specializes in the dynamics of the earth's iron core. I asked him if the last time a pole reversal occurred was nearly a million years ago, wouldn't that mean current surface life, including humans and geophysicists, have no idea what actually happens if the poles reverse?
Interviews Mathieu Dumberry, Graduate Assistant to Prof. Jeremy Bloxham, Department of Earth and Planetary Sciences, Harvard University, Cambridge, Massachusetts: "That's correct. The consequences for human life, in terms of what the actual exact sort of strength decrease in the overall magnetic field is and in terms of what the consequences are for the solar particles that are trapped in the magnetic field of the earth is, we don't really have a good idea on that.
The magnetosphere plays such a strange and mysterious, but important role between the ionosphere, outer space and here on the earth. There are aurora borealis and all kinds of magnetic field effects. If the North and South poles suddenly changed and the magnetic fields were coming out of the North Pole and entering the South Pole, wouldn't you think there might be some dramatic effects on earth life?
I think the most dramatic effects might occur during the reversal that is when the strength of the dipole field is going to be the weakest. Because if the dipole is oriented one way or another in terms I'm thinking in terms of the solar particles that are trapped in the magnetic field therefore, don't reach the surface of the earth. These sort of high energy particles could be damaging to life on the earth. If these particles are trapped by the fields, they don't reach the surface.
However, if the strength of the dipole field decreases, then the ability of the magnetic field to stop these highly energetic particles is weakened. And so this might have an affect on life.
But, as I said earlier, 780,000 years ago when it happened, of course, we did not have human society as we have now today, but the creatures that lived then in terms of humans and other animals have survived.
Some have. But there have been periods of unexplained extinctions in the history of the earth. If I understand what you are saying, strong solar particles could be able to reach the surface of the earth uninterrupted by strong magnetic fields as they are deflected today. Such energetic particles reaching the surface of the earth unimpeded