--- In firstname.lastname@example.org
, XK SAZ <group@s...> wrote:
> What makes the earth's magnetic field suddenly shift from south to
> north? Anything specific?
> It's as if a person standing with their face to the wind turns and
> walks backwards so they won't get so much dust in their eyes.
I think you're getting the Earth's magnetic field confused with the
Interplanetary Magnetic Field. Earth's magnetic field does indeed
swap ends occasionally, but it only happens every few hundred thousand
years. Einstein said that how the Earth's magnetic field is generated
is one of the greatest mysteries of modern physics. Nobody is certain
of exactly how it works. It's presumed that it has something to do
with motion of liquid iron in the Earth's outer core, but beyond that,
not much else is known. The occasional polarity shifts are equally
The Interplanetary Magnetic Field (IMF) originates at the sun, is
carried along by the solar wind. It shifts polarity frequently. A
north-pointing IMF will reinforce Earth's magnetic field and tend to
suppress geomagnetic activity. A south-pointing IMF has exactly the
Believe it or not, the sun's magnetic field also reverses every 11
years at the peak of the sunspot cycle.