NOAA releases early update for World Magnetic Model

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For example, airport runway names are based on their direction toward magnetic north and their names change when the poles move.

There have been a few theories about why the pole's movement has increased in recent years - from around 6 miles a year between 1900 and 1980 before accelerating to around 24 to 31 miles a year in the past two decades.

The World Magnetic Model (WMM) enables compasses to point north and is used in navigation systems and was updated to keep it accurate.

The Earth's northern magnetic pole is on the move, scientists say, drifting from the Canadian Arctic towards Siberia. Scientists this week have updated the location of magnetic north a year ahead of schedule.

At the moment, the northern magnetic pole is moving away from the Canadian Arctic and toward Siberia.

The military depends on where magnetic north is for navigation and parachute drops, while NASA, the Federal Aviation Administration and US Forest Service also use it. Global Positioning System is not affected because it's satellite-based.

The U.S. National Oceanic and Atmospheric Administration and United Kingdom tend to update the location of the magnetic north pole every five years in December, but this update came early because of the pole's faster movement.

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More than anything, the shift of the Magnetic North Pole affects navigation systems containing magnetic compasses. Its speed jumped from about 9 miles per year (15 kilometers per year) to 34 miles per year (55 kilometers per year) since 2000.

"The difficulty is that we don't have a way to directly observe what is happening in the Earth's core so we have to make a lot of assumptions", Arnaud Chulliat, a geomagnetist at the University of Colorado Boulder and NOA, who works on the WMM, told Motherboard. Earth's magnetic field is created in its liquid outer core, which is made of liquid iron and nickel.

For most civilian purposes in Western Europe and North America, British Geological Survey geophysicist Ciaran Beggan says the changes would be relatively minor.

Since the model is created and released by the National Oceanic and Atmospheric Administration, the USA government shutdown delayed the release of the latest data set. And unlike the geographic north pole, which is fixed, the north magnetic pole has been slowly migrating over time - moving across the Canadian Arctic toward Russian Federation since 1831. Research into rock signatures has shown that this can happen about every 250,000 years, except for the last one - that happened around 780,000 years ago.

'It's not a question of if it's going to reverse, the question is when it's going to reverse, ' Mr Lathrop said. And while most scientists believe this shift will not lead to any catastrophic mass extinctions, the scenes may be frightening, looking something like the pictures of thousands of dead birds and fish in Arkansas in 2011, which some scientists thought may have been related to animals' sensitivity to changes in the Earth's magnetic field.

This pole is defined as the point at which magnetic field lines point vertically down.

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