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The mysterious anomaly that weakened the Earth’s magnetic field seems to be shared

New satellite data from the European Space Agency (ESA) reveals that the mysterious deviation weakening the Earth’s magnetic field continues to evolve, with the latest observations showing that we could soon deal with more than one of these strange phenomena.

The South Atlantic anomaly is a large expanse of decreased magnetic intensity in the Earth’s magnetic field and extends all the way from South America to southwest Africa.

Since our planetary magnetic field acts as a kind of shield – protecting the earth from solar winds and cosmic radiation, in addition to determining the position of the magnetic poles, any decrease in its strength is an important event that we must follow closely, as these changes can ultimately have significant consequences for our planet. planet.

At present, there is nothing to be worried about. ESA notes that the most significant effects right now are largely limited to technical disruptions aboard satellites and spacecraft, which may be exposed to a larger amount of charged particles in low Earth orbit as they pass through South Atlantic Anomaly in the skies above South America and the South Atlantic.

But not that the size of the anomaly should be reduced. Over the past two centuries, the Earth’s magnetic field has lost about 9 percent of its power on average, says ESA, with a reduction in the minimum field strength of South Atlantic Anomaly from about 24,000 nanotlases to 22,000 nanotlases over the past 50 years.

Exactly why this happens remains a mystery. The Earth’s magnetic field is generated by electric currents produced by a swirling mass of liquid iron in our outer core, but even though this phenomenon seems stable at a certain point in time, over large time scales, it is never really quiet.

Research has shown that the Earth’s magnetic field is constantly in a state of flow, and that every hundred thousand years (give or take) the Earth’s magnetic field turns with the northern and southern magnetic poles that change place.

That process may actually happen more often than people think, but while scientists are constantly debating when we next testify of such an event, we even guess the regular, wandering movements of the earth’s magnetic poles.

In any case, it is not entirely clear how these twists and turns can be linked to what is currently happening with South Atlantic Anomaly – which some have suggested could be caused by a huge dense rock reservoir under Africa called the African Large Low Shear Velocity Province.

But what is certain is that South Atlantic Anomaly is not sitting still. Since 1970, the anomaly has increased in size and moved west at a rate of about 20 kilometers per year. But that’s not all.

010 esa south Atlantic anomaly 1(Division of Geomagnetism, DTU Space)

Above: Satellite data revealing the new, eastern center of least intensity emerging alongside Africa.

New readings from ESA’s Swarm satellites show that within the last five years, a second center of minimum intensity has begun to open in the anomaly.

This suggests that the whole thing could even be divided into two separate cells – with the original just above South America, and the new, emerging cell emerging in the east, hovering outside southwest Africa.

“The new eastern minimum of South Atlantic Anomaly has emerged in the last decade and in recent years is developing strongly,” says geophysicist Jürgen Matzka of the German Geosciences Research Center.

“The challenge now is to understand the processes in the earth’s core that drive these changes.”

How the anomaly will develop from here is unknown, but previous research has suggested disturbances in the magnetic field as this may be recurring events that occur every hundred years.

Whether that is what we are witnessing now is not entirely clear – or how a split deviation may come into play – but researchers are keeping a close eye, as we are.

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