The North Magnetic Pole
is a spot on the top
of the planet where the
Earth’s magnetic field lines
converge and drive
straight into its core.
Since scientists
have been tracking this,
the North Magnetic Pole
has been shifting
towards Russia.
The planet’s inner core
is made of solid iron,
while surrounding that
is a molten metallic
outer core.
From there, heat escapes,
creating electric currents
in the conductive iron alloys
in the core.
THE DYNAMO EFFECT
The Earth
itself spins
on its axis.
The inner core spins
at a different rate
than the outer core.
This creates
a dynamo effect
that enables the
Earth’s magnetic field.
Satellite data tracking
the Earth’s magnetic field
show the pole is moving
faster across the Arctic
than previously recorded.
The rate
of movement
has increased
in recent history:
This is happening because
of a push and pull between
two unusually strong magnetic
patches in the Earth’s outer core.
One patch under Canada.
One patch under Siberia.
The North Magnetic Pole
has historically been
within Canadian borders
because of stronger pull
of the Canadian magnetic
patch, but that is changing.
Scientists can study
the moving poles
by examining
the rocks lying on
the ocean floor
that captured
magnetic traces
of previous
orientations
of the Earth’s
magnetic field.
The last time
the poles switched
( aka "flipped" ) was
~780,000 years ago,
and it has happened
about 400 times
in 330 million years.
Each reversal takes
one thousand years
to complete.
The magnetic field
has weakened 10%
in the last 150 years.
Some scientists think
that's a sign of a "flip"
in progress.
In 2013, the European Space
Agency (ESA) launched
the SWARM mission to study
the Earth’s magnetic field
using satellites.