Proactive disclosure Print version ![Print version Print version](/web/20061103053756im_/http://www.gsc.nrcan.gc.ca/esst_images/_printversion2.gif) ![ÿ](/web/20061103053756im_/http://www.gsc.nrcan.gc.ca/esst_images/_spacer.gif) | ![ÿ](/web/20061103053756im_/http://www.gsc.nrcan.gc.ca/esst_images/_spacer.gif) | ![Geological Survey of Canada Geological Survey of Canada](/web/20061103053756im_/http://www.gsc.nrcan.gc.ca/esst_images/gsc_e.jpeg) Natural Resources Canada > Earth Sciences Sector > Geological Survey of Canada > Geomagnetism
Geomagnetism Daily Movement of the North Magnetic Pole
It is important to realize that the position of the North Magnetic
Pole given for a particular year is an average position. The Magnetic
Pole wanders daily around this average position and, on days when the
magnetic field is disturbed, may be displaced by 80 km or more. Although
the North Magnetic Pole's motion on any given day is irregular, the
average path forms a well-defined oval. The diagram shows the average
path on disturbed days.
![the average path on disturbed days](/web/20061103053756im_/http://www.gsc.nrcan.gc.ca/geomag/nmp/images/nmpoval2001d_e.gif)
The cause of the North Magnetic Pole's diurnal motion is quite different
than that of its secular motion. If we measure the Earth's magnetic
field continually, such as is done at a magnetic
observatory, we will see that it
changes during the course of a day
- sometimes slowly, sometime rapidly.
The ultimate cause of these fluctuations is the Sun. The Sun constantly
emits charged particles that, on encountering the Earth's magnetic field,
cause electric currents to flow in the ionosphere and magnetosphere.
These electric currents disturb the magnetic field, resulting in a temporary
shift in the North Magnetic Pole's position. The size and direction
of this shift varies with time, in step with the magnetic field fluctuations.
Since such fluctuations occur constantly, the Magnetic Pole is seldom
to be found at its "official" position, which is the position
in the absence of magnetic field fluctuations.
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