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Polar drift

From Wikipedia, the free encyclopedia
The North Magnetic Pole's drift

Polar drift is a geological phenomenon caused by variations in the flow of molten iron in Earth's outer core, resulting in changes in the orientation of Earth's magnetic field, and hence the position of the magnetic north- and south poles.

The North magnetic pole is approximately 965 kilometres (600 mi) from the geographic North Pole. The pole drifts considerably each day, which results in a change of 5-60 km per year. The speed of the change was around 10 km/year for the majority of the 20th century, then increased in the 1990s to over 50 km/year, but slowed down slightly after 2020.[1] [2]

The South magnetic pole is constantly shifting due to changes in the Earth's magnetic field. As of 2005 it was calculated to lie at 64°31′48″S 137°51′36″E / 64.53000°S 137.86000°E / -64.53000; 137.86000,[3] placing it off the coast of Antarctica, between Adélie Land and Wilkes Land.

In 2015, it lay at 64°17′S 136°35′E / 64.28°S 136.59°E / -64.28; 136.59 (est).[4] That point lies outside the Antarctic Circle and it is moving northwest by about 10 to 15 km (6 to 9 mi) per year. Its current distance from the actual Geographic South Pole is approximately 2,860 kilometres (1,780 mi).[5] The nearest permanent science station is Dumont d'Urville Station. Wilkes Land contains a large gravitational mass concentration.

See also

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References

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  1. ^ North Magnetic Pole Moving Due to Core Flux, National Geographic News, December 24, 2009
  2. ^ International Geomagnetic Reference Field: the thirteenth generation (2021) Retrieved 2024-11-24
  3. ^ "Geomagnetism Frequently Asked Questions". NGDC. Retrieved 11 January 2009.
  4. ^ a b c British Geological Survey – Magnetic Poles
  5. ^ NOAA National Geophysical Data Center. "Wandering of the Geomagnetic Poles". Retrieved October 10, 2011.
  6. ^ "Geomagnetism, North Magnetic Pole". Geological Survey of Canada. Natural Resources Canada. Archived from the original on 26 March 2010. Retrieved 12 January 2019.
  7. ^ World Data Center for Geomagnetism, Kyoto. "Magnetic North, Geomagnetic and Magnetic Poles". Retrieved 2019-01-12.
  8. ^ "Poles and Directions". Australian Antarctic Division. 2011. Retrieved October 11, 2011.
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