Earth Magnetic Field Decline

The earth's geomagnetic magnetic field strength was first measured in the 1830's. Since that time it has declined almost ten percent. That decline rate is about twenty times faster than the natural decline rate would have been if the power source creating the earth's magnetic field had completely stopped, so there obviously must be some other cause. It is known that the polarity of earth's magnetic field has flipped from north to south and back again hundreds of times in the past. A popular current theory is that it may be in the process of flipping again. However, the flips are thought to be caused by a complexity of chaotic process in earth's outer core, so instead of reversing, the field strength could quickly rise again with its current polarity and the next reversal could be far in the future. ©2005 Tigertek, Inc. All rights reserved.

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