Home / Science / Will Earth's magnetic field be reversed soon?

Will Earth's magnetic field be reversed soon?

Earth's northern magnetic pole is so messed up that scientists need to update the global magnetic field model they released four years ago. Could this be a sign that the magnetic pole will soon topple?

The World Magnetic Model (WMM) – the name of the updated Earth's magnetic field – is not expected to be released before January 30. This is about two weeks later than planned, with the delay due to the government shutdown, according to a report in Nature.

The magnetic pole moves unpredictably from the Canadian Arctic and towards Siberia, so unpredictably that it surprised scientists. The 2015 update should remain valid until 2020, said Arnaud Chulliat, a geomagnetist at the University of Colorado Boulder and the National Centers for Environmental Information (NOAA) of the National Oceanic and Atmospheric Administration (NOAA), told Nature. [Earth̵

7;s Colorful Atmospheric Layers Photographed from Space]

There is no news that the rod is moving; Long-term records from London and Paris (kept since 1580) show that the northern magnetic pole is irregularly moving around the rotating North Pole over a period of several hundred years or more, with WMI updates being shared by Ciaran Beggan, a British Geological Survey geophysicist Space.com said via email. He cited a study from 1981 from the journal Philosophical Transactions of the Royal Society of London.

But what attracts attention is the acceleration of the movement. Around the mid-1990s, the pole suddenly accelerated its movements from just over 15 km per year to 55 km per year. Since last year, the pole has turned over the international date line towards the eastern hemisphere.

The main cause of the movement is the liquid iron core of the Earth, also called the "core field". Smaller factors also influence the movement. These influences include magnetic minerals in the crust and upper mantle (especially for local magnetic fields) and electrical currents caused by the "circulating magnetic field" of seawater, as described in WMM's 2015 report.

"One of the reasons We can update the map: The European Space Agency introduced a set of highly accurate magnetic field satellites in 2013," said Beggan, referring to Swarm.

"We have an excellent record that allows us to magnetize very well-field maps and update them every six to twelve months," Beggan added. "We found that the specification of the WMM in the high latitude around the pole was not respected because the error averaged over a 1 degree screen angle, which led us to consider whether it would be worthwhile issuing a new update."

In addition, the core field seems to be weakening – which could be a sign that the magnetic field of the planet is going to tip over. To better understand how this would happen, Ronald Merrill, Emeritus Professor of Earth and Space Sciences at the University of Washington, explains how he spoke with the headquarters of Space.com, the Space.com live site.

A Simple Thing The field can only be imagined when one thinks of a bar magnet that runs through the center of the earth and has a north and a south pole, said Merrill, who was not involved in the new WMM research. This magnet is strong and represents about 75 percent of the Earth's magnetic field at the surface.

Of course, a bar magnet is not a perfect representation – it's actually electric currents that create the earth's magnetic field – but the model makes it easier Imagine what happens to the earth, Merrill added. In fact, the "bar magnet" does not only move, but also gets weaker by about 7% every 100 years.

Like the other 25% of the magnetic field, so Merrill, this is generated from another field that you can image as another moving bar magnet. Here is an interesting piece: As the central bar magnet loses intensity, this second, weaker magnetic field has more influence on the global magnetism of the earth. "And that's why this field is moving in the direction [of Siberia]," Merrill told Live Science.

The north and south poles of the earth regularly swap locations, with the last flip occurring about 780,000 years ago. (Also, the poles were temporarily and rapidly weakened about 41,000 years ago, Beggan added, but never underwent a full turnaround.)) A 2018 study in the Proceedings journal of the National Academy of Sciences suggested that the magnetic field Earth became weaker before the big changeover.

Although a magnetic field flip would be thousands of years away, the impact on technology could be profound if it resembles today's technology. This is because the weaker magnetic field in shielding the earth from the solar wind (the constant stream of charged particles emanating from the sun) and the cosmic rays (radiation rays from deep space) would be slightly worse. Magnetic compasses would not be so accurate, and satellites that monitor the weather or transmit telecommunications signals could be disturbed, said Monika Korte, head of the GFZ Potsdam working group on the development of geomagnetic fields in Germany.

"In terms of increased radiation, which would be accompanied by reduced shielding [but]the atmosphere at the surface of the earth still seems to provide sufficient shielding so that humans and animals are not significantly affected," she said in an interview with Space.com Email.

"All the effects we currently experience only in severe solar / geomagnetic storms would likely increase and occur … with moderate solar activity," she added. "These include satellite failures or damage to satellites, increased radiation doses in long – haul aircraft and the distortion of telecommunications and GPS signals by ISS [International Space Station][and].

Ongoing monitoring of the Earth's geomagnetic field (including the Pole) will continue after the WMM release, mainly due to the European Space Agency's swarm mission, Korte said. She noted, however, that measuring the position of the North Magnetic Pole is a challenge. This is because the pole is located in a remote area and the measurement of the Earth's magnetic field is affected by all magnetic field sources – including the magnetic fields in the Earth's atmosphere (ionosphere and magnetosphere).

"It will depend on the future magnetic field change that we can not predict if another update of the model is needed," she added.

The next WMM update after this year is expected in early 2020, Beggan said. Find out more about the WMM here. Follow

@Spacedotcom and on Facebook. Original article on Space.com

Source link