Now, maybe 6 or 7 years later, I've just rediscovered my childhood fear while reading about the magnetic poles in my textbook. I tried to find the same documentary that scared me all those years ago, but all that I could find was a documentary broadcasted by PBS called Magnetic Storm and an episode of "The Nature of Things" called When North Goes South. I've learned many things from both of these documentaries, but the gist of this whole idea is that scientists have deduced from the direction of magnetism of older rocks that in Earth's history, the poles have flipped roughly every 200,000 to 300,000 years. The ominous part however, is that we are long overdue for a pole reversal; they haven't flipped for 780,000 years [source].
Before a reversal, the magnetic field's strength usually weakens very slowly, but our field seems to be weakening a lot faster than usual: at about 5 percent per decade rather than 5 percent per century [source].
The Earth's magnetic field protects us from solar wind, which is essentially just radiation from the sun. Without the protective magnetic field, cancer rates would increase and genetic mutations are possible, however it's debatable whether the increase in cancer rates will be enough to even be noticeable [source].[gif source]
Most likely the worst affect that we'll get from the reversal of the poles is an interruption in our
electric grid. Okay, so that seems like no big deal, but with our growing dependence on technology, the human race will likely be heavily impacted by the solar storms that can now get close enough to affect satellites. Most of the problems thus far have been in the northern hemisphere, where the field is weakest, but with the wandering pole, the effects could easily spread [source].
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It is highly unlikely that the field would disappear completely (if that happened, we really would be in trouble) because it's formed by the convection currents of molten iron in Earth's core. The iron will cool down eventually, which is exactly what happened to Mars billions of years ago, but not for a very very long time [source]. The convection creates electrical currents which then create the magnetic field that protects us from the dangerous radiation from the sun.
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Both documentaries suggested that during the process of the polar flip, there will likely be not only two, but several different north and south poles around the globe. It would probably mean a lot of confusion with navigation, and maybe some electrical problems, but nothing more serious than that.
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Just as every magnet has a positive pole, every problem has a bright side! During the magnetic flip, the Aurora Borealis/Australis will be visible all around the world, almost every night. So when your satellite TV isn't working because the satellite has been damaged by some pretty harsh solar storms, you'll have something to look at!
*All gifs made by me from this video
What Will Happen When the Earth's Magnetic Field Switches. (2014, April 17). Retrieved October 20, 2014, from http://gizmodo.com/what-will-happen-when-the-earth-s-magnetic-field-switch-1564164183
Dickerson, K. (2014, July 9). Earth's Magnetic Field Flip Could Happen Sooner Than Expected. Retrieved October 20, 2014, from http://www.scientificamerican.com/article/earth-s-magnetic-field-flip-could-happen-sooner-than-expected/
What Happens When The Poles Flip? (2014, March 20). Retrieved October 20, 2014, from http://www.universetoday.com/110475/what-happens-when-the-poles-flip/
Dunbar, B. (2011, December 5). 2012: Magnetic Pole Reversal Happens All The (Geologic) Time. Retrieved October 20, 2014, from http://www.nasa.gov/topics/earth/features/2012-poleReversal.html
Earth's magnetic field can flip in less than 100 years, new study. (2014, October 25). Retrieved October 20, 2014, from http://thewatchers.adorraeli.com/2014/10/15/earths-magnetic-field-can-flip-in-less-than-100-years-study/
Nova - Magnetic Storm - Earth's Invisible Shield. Retrieved October 20, 2014, from http://www.youtube.com/watch?v=NJUTUFAWfEY
When North Goes South - The Nature of Things. (2013, April 10). Retrieved October 20, 2014, from http://www.cbc.ca/natureofthings/episodes/when-north-goes-south
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