
Pole reversal estimate, less than 100 years - ChuckMcM
http://gji.oxfordjournals.org/content/199/2/1110
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ChuckMcM
This has been something that fascinated me the first time I heard of it, the
North and South poles of the planet shifting. Recent work on sediments in a
lake have given a much better estimate of the time it took and reduced it from
"less than 1000 years" to "less than 100". Further, the lack of sediment
showing inter-pole positions means it might have been practically
instantaneous. That would be a pretty wild thing to live through.

~~~
Igglyboo
How would it affect daily life other than compasses being wrong? Would
humanity even survive it?

~~~
gus_massa
The standard answer is that the magnetic field protects us from part of the
radiation that comes from the space. I tried to find a good source with more
information. I'm still not sure, perhaps it's only a myth.

This page says that if there were no magnetic field, the atmosphere would
absorb the radiation anyway. (I vote for this, but I'd like to see more info.)
[http://www.sciencebits.com/NotReallyAProtection](http://www.sciencebits.com/NotReallyAProtection)

These two pages say that the magnetic field provides protection:
[http://www.windows2universe.org/glossary/plasmaspheric_gain....](http://www.windows2universe.org/glossary/plasmaspheric_gain.html)
[http://www.askamathematician.com/2014/07/q-how-does-
earths-m...](http://www.askamathematician.com/2014/07/q-how-does-earths-
magnetic-field-protect-us/)

~~~
fataliss
But a shift in polarisation wouldn't include the field to disappear at any
time, would it?

~~~
gus_massa
From:
[http://en.wikipedia.org/wiki/Geomagnetic_reversal](http://en.wikipedia.org/wiki/Geomagnetic_reversal)

> _During this change the strength of the magnetic field dropped to 5% of its
> present strength._

> _The magnetic field will not vanish completely, but many poles might form
> chaotically in different places during reversal, until it stabilizes
> again.[_

