News & Press: Natural world

New World Magnetic Model released

24 December 2019   (0 Comments)
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The British Geological Survey (BGS) and US National Oceanic and Atmospheric Administration (NOAA) have published a new magnetic model for the period 2020-25.

The WMM is a standard model of the core and large-scale crustal magnetic field.  Due to changes in the Earth’s core field, it is updated every 5 years and constantly checked against data from 160 ground-based magnetic observatories and ESA’s Swarm magnetic-field mapping satellites. The measurements are used to construct a complex representation of the many different sources of Earth's magnetic field and its time variation.

The 2020 model shows magnetic north crossing the Northern Hemisphere at ~50 km per year, moving from the Canadian Arctic towards Siberia. BGS geophysicist Ciaran Beggan comments:
’It’s the fastest recorded shift seen since the mid 16th-century. Magnetic records show the magnetic North Pole has been meandering about Canada from 1590 until 1990, when it suddenly accelerated to gain speed over the past 30 years, going from less than 10 km per year to almost 60 km per year. However, on the other side of the planet, the South Magnetic Pole has moved very slowly, drifting around the coast of Antarctica in the same period.’

To discover 14 parameters on declination (variation), inclination and their rates-of-change, enter lat/long,  altitude and date into the Model found at the BGS

Image from BGS