Sunday, June 23, 2013

Magnetic Pole Reversal NOT a Sign of Doomsday

EarthSky Magazine has an article on magnetic pole reversals:

Reversals are the rule, not the exception. Earth has settled in the last 20 million years into a pattern of a pole reversal about every 200,000 to 300,000 years, although it has been more than twice that long since the last reversal. A reversal happens over hundreds or thousands of years, and it is not exactly a clean back flip. Magnetic fields morph and push and pull at one another, with multiple poles emerging at odd latitudes throughout the process. Scientists estimate reversals have happened at least hundreds of times over the past three billion years. And while reversals have happened more frequently in “recent” years, when dinosaurs walked Earth a reversal was more likely to happen only about every one million years.
Of course, that doesn't mean that bad things might not happen. At a minimum it will mess with any navigation, by man or animal, that relies on magnetism.

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