> (3) We also seem to be overdue for polar magnetic reversal, where the Magnetic North Pole becomes South Pole, in a colossal 'flip-flop'. The earth's magnetic field has reversed approximately 170 times over the last 100 million years. I don't know how much of our modern technologies are still dependant on the location of Magnetic North; but it's possible that it will create mass extinctions in species who have developed sensitivity to magnetic flux flows (used as guidelines in migratory patterns).

If this happens, wouldn't we also see dramatically increased levels of solar radiation reaching the earth? It probably depends on how long a reversal requires.

And then, to needlessly complicate matters, the draining of lakes has been known to produce alternating magnetic bands almost identical to those found around rifts in the ocean floor, the single best evidence for pole reversals. So maybe we aren't due for a reversal.

gab"Better stock up on our sunblock..."by