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Is Earth's magnetic field a quick trigger?



The North Magnetic Field of Earth is so overwhelming that scientists need to update the global magnetic field model that they published just four years ago. Can this be a sign that the magnetic field will soon turn?

It is expected that the World Magnetic Model (WMM) – the name of the updated Earth Earth Magnetic Display – will be released early January 30th. It is about two weeks later than planned, with a delay due to the government's closure, according to Nature's report.

The magnetic pole is unpredictably moving beyond the Canadian Arctic and towards Siberia so unpredictable that scientists are surprised. This update for 2015 should remain in place by 2020, Nature Arnaud Chulliat, geomagnetist from Colorado Boulder University and the National Oceanic and Atmospheric Administration National Environmental Information Center (NOAA) said. [Earth’s Colorful Atmospheric Layers Photographed from Space]

There is no news that the stick moves; Long-lasting records from London and Paris (held from 1580) show that the northern magnetic pole is irregularly moving around the rotating north pole for several hundred years or longer, Ciaran Beggan, a geophysicist with the British Geological Survey involved in WMM updates, said Space.com in email. He quoted a 1981 study from the Philosophical Transactions of the Royal Society of London.

But what really attracted attention is acceleration on the move. In the middle of the 1990s, a half had suddenly accelerated its movements from just over 15 kilometers per year to 55 kilometers per year. Since last year, the poles have stretched over the international date line towards the eastern halfway.

The main cause of the movement comes from the Earth's outer core iron-iron, also called the "central field". Fewer factors also affect the movement. These impacts include magnetic burial minerals and upper cladding (especially for local magnetic fields) and electricity generated by seawater moving through the "ambience magnetic field," according to WMM's 2015 report.

"One of the reasons we can update the map is that the European Space Agency in 2013 launched a set of highly accurate satellite magnetic fields," Beggan said, thinking of Swarm.

"We have an outstanding data set from which we can make very good maps of magnetic fields and update them every six to 12 months," Beggan added. "We noticed that the WMM specification was not met in the area of ​​a high latitude of about half, as the error averaged an average of 1 degree, which prompted us to investigate whether it was worth updating."

Moreover, it seems that the central field weakens – which may be a sign that the magnetic field of the planet will turn. To better understand how this will happen, here's how the core field works, says Ronald Merrill, professor emeritus of Earth and Space Science at Washington University, who spoke with Space.com's sister site Live Science.

One easy way to imagine a field is to think of a magnet that goes through the Earth's center and has the north and south poles, Merrill said, who was not involved in new WMM research. This magnet is strong, representing about 75 percent of the intensity of the Earth's magnetic field on the surface.

Of course, the rod magnet is not a perfect representation – it's actually electricity generated by the Earth's magnetic field – but the model makes it easier to imagine what is happening on Earth, Merrill added. Namely, "bar magnet" not only moves, but becomes weaker, roughly 7 percent every 100 years.

As for the other 25 percent of the magnetic field, Merrill said that it was generated from another field, which you could imagine as another moving magnet. Here's one interesting bit: As the central magnetic rod loses its intensity, this second, weaker magnetic field creates a greater impact on the global magnetism of the Earth. "And that is what causes this field to move in the direction [of Siberia], "Merrill said Live Science.

The North and South poles of the Earth occasionally replace locations, and the last flip occurs about 780,000 years ago. (The poles also temporarily and quickly weakened roughly 41,000 years ago, Begun added, but he has never had a full swing.) The 2018 study in the Proceedings of the National Academy of Sciences showed that the Earth's magnetic field weakened before major changes .

While any magnetic field overlap has still been remote for thousands of years, the effects could be profound on technology if it is similar to today's technology. The reason is that the weaker magnetic field would be somewhat weaker than Earth's solar wind protection (constant flow of charged sun-bearing particles) and cosmic air (deep-space radiation explosion). Magnetic compasses would not be accurate, and satellites that observe weather conditions or carry telecommunication signals could be disrupted, said Monica Korte, GFZ Potsdam's leader of the geomagnetic field evolution in Germany.

"With regard to increased radiation, this would be in line with reduced protection, [but] it seems that the atmosphere still provides enough protection on Earth's surface that people and animals would not be significantly affected, "she said.

"However, all the effects we currently see only during strong solar / geomagnetic storms will likely increase and appear … during moderate solar activity," she added. "This includes satellite breaks or satellite damage, increased radiation doses at large distances and ISS [International Space Station]. [and] distortion of telecommunication and GPS signals. "

Continuous monitoring of the Earth's geomagnetic field (including half) will continue after the release of WMM, primarily through the mission of the European Space Agency, said Korte. However, he noticed that measuring the position of the northern magnetic pole is a challenge. This is because the pole is located in the remote area and all magnetic field sources – including the magnetic fields found in the Earth's atmosphere (ionosphere and magnetosphere) – are influenced by Earth's magnetic field.

"This will depend on future magnetic field changes, which we can not foresee if it would be necessary to update the template from the normal schedule," she added.

The next update of WMM after this year is expected in early 2020, Beggan said. You can read more about WMM here.

Follow us on Twitter @Spacedotcom and on Facebook. A source article on Space.com.


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