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The pole mystery.

A article published recently speculates that the poles have been in different spots at various points in Earths History. The poles have been shifting for awhile and they are drifting south west if I remember correctly.

 

New work from Peter Driscoll, a staff scientist at DTM, suggests Earth’s ancient magnetic field was significantly different than the present day field, originating from several poles rather than the familiar two. It is published in Geophysical Research Letters.

Earth generates a strong magnetic field extending from the core out into space that shields the atmosphere and deflects harmful high-energy particles from the Sun and the cosmos. Without it, our planet would be bombarded by cosmic radiation, and life on Earth’s surface might not exist. The motion of liquid iron in Earth’s outer core drives a phenomenon called the geodynamo, which creates Earth’s magnetic field. This motion is driven by the loss of heat from the core and the solidification of the inner core.

Ancient Earth poles

Furthermore.

Wandering of the Geomagnetic poles

Geomagnetic poles

Magnetic poles are defined in different ways. They are commonly understood as positions on the Earth’s surface where the geomagnetic field is vertical (i.e., perpendicular) to the ellipsoid. These north and south positions, called dip poles, do not need to be (and are not currently) antipodal. In principle the dip poles can be found by conducting a magnetic survey to determine where the field is vertical. Other definitions of geomagnetic poles depend on the way the poles are computed from a geomagnetic model. In practice the geomagnetic field is vertical on oval-shaped loci traced on a daily basis, with considerable variation from one day to the next.

Experimental observations of dip poles

It has been long understood that dip poles migrate over time. In 1831, James Clark Ross located the north dip pole position in northern Canada. Natural Resources Canada (NRCan) tracked the North Magnetic Pole, which is slowly drifting across the Canadian Arctic, by periodically carrying out magnetic surveys to reestablish the Pole’s location from 1948 to 1994. An international collaboration, led by a French fundraising association, Poly-Arctique, and involving NRCan, Institut de Physique du Globe de Paris and Bureau de Recherche Geologique et Miniere, added two locations of the North Magnetic Pole in 2001 and 2007. The most recent survey determined that the Pole is moving approximately north-northwest at 55 km per year.A web based portal is available to view both the experimental and modeled pole locations here.

 

 

Pole Shift

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About dgarnold

More interests than I can count.. enjoy Foreign Policy, Current events, Books, Game theory,Sports (both watching and participating) and of course my Labradors. Love Mountain Biking! World class backgammon player.

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