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Scientists caught flatfooted by an increasingly "capricious" Magnetic North

Source: Xinhua| 2019-01-13 14:24:01|Editor: xuxin
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WASHINGTON, Jan. 13 (Xinhua) -- The geomagnetic field makes lives possible by deflecting harmful radiation and keeping water and atmosphere in place. But now it's acting up, with increasingly unpredictable bipolar course change which renders compasses redundant.

Unlike previous anomalies recorded at intervals averaging several hundred thousand years, recent movements of the magnetic poles have been alarmingly "erratic" -- frequent and faster -- from around 15 km per year before the mid-1990s to around 55 km right now, skittering away from Canada and towards Siberia, according to science journal Nature.

The Earth's magnetic field is generated in the fluid outer core of sloshing molten iron by a self-exciting dynamo process. However, abrupt and irregular changes within the core has prompted scientists to update the World Magnetic Model, which describes the the planet's magnetic field and underlies all modern navigation, from the systems steering ships at sea to Google Maps on smartphones.

The Clock is ticking right now for geomagnetists to release the updated model by the Jan. 15 deadline, the most recent of which issued in 2015 and supposed to last until 2020, according to Nature.

Researchers from the U.S.-based National Oceanic and Atmospheric Administration and the British Geological Survey in Edinburgh has been checking annually to see if the model is able to capture all the variations in Earth's magnetic field.

Starting 2018, the World Magnetic Model was not functioning well, its precision close to exceeding "the acceptable (safe) limit for navigational errors," Nature reported.

Besides such errors, a disrupted geomagnetic field may also leave living beings on the planet vulnerable to an increased dosage of solar radiation.

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