Is the Earth’s magnetic field about to reverse?

The Earth’s magnetic field is an important physical aspect of our planet, protecting us from radiation and geomagnetic activity that can affect satellite communications and the planet’s power grid. Scientists have studied and observed this magnetic field for centuries, and they already know one important aspect: it moves and changes the planet’s poles.

This movement does not usually cause problems, which will only happen in the event of a pole shift, which affects the climate and modern technology. But this only happens over thousands of years. But how is the planetary magnetic field formed?

How do magnetic fields arise?

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Magnetic fields are generally formed as a result of moving electrical charges, and materials that allow the movement of these charges are called conductors. They transfer electrical currents from one place to another, and these currents are negative charges (electrons) moving along conductive metals. This current generates a magnetic field.

There are layers of conductive materials in the Earth’s core from iron magma. Watch the example in the video below (in English):

At the center of the planet, currents of charge move, just like liquid iron, and these circular movements generate the entire Earth’s magnetic field. It’s not just our Earth that has this property. Gas giant planets, like Jupiter, have a layer of conductive metallic hydrogen that generates their own magnetic fields.

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The motion of conductive layers generates two types of fields: larger fields, such as large-scale planetary rotation, generate north-south symmetrical fields, like small magnets, and smaller fields, which can arise when there are anomalies in a larger field due to flows that do not follow the pattern Large-scale magnetic or local disturbance. These irregularities also arise in places where the magnetic field deviates from an ideal dipole.

Over time, these anomalies can generate significant changes in the primary magnetic field, even reversing it, putting north in south and vice versa. This definition is even reflected on our planet, where magnetic north is located at the South Pole (Antarctica) and magnetic south is located at the North Pole (Arctic).

Will the magnetic field be reversed?

The Earth’s magnetic field creates a kind of bubble above the ionosphere, the outer part of the atmosphere, called the magnetosphere. It protects the planet by reflecting high-energy cosmic radiation resulting from star explosions throughout the universe, in addition to interacting with the solar wind and magnetic gases emitted by the sun, and in the video below we can see very illustratively how this protection works:

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When large clouds of gas are emitted from the star, their interaction with the magnetosphere can generate geomagnetic storms, which can generate aurora borealis. However, when there is too much radiation, “cosmic weather” can negatively affect astronauts, satellites and Earth’s conducting networks, such as power and gas.

According to the scientists’ analysis, the Earth’s magnetic north pole has moved about 965 kilometers since the first measurement in 1831. The speed of this migration has increased since then, from 16 kilometers per year to 54 kilometers per year, which may indicate an imminent reversal. But they are difficult to predict using less than 200 years of data.

From records of volcanic rocks in the sea, we know that polar reversals occurred at intervals of 100,000 to 1,000,000 years. On a geological level, reversals are fast, but from a human perspective, they are very slow, occurring over thousands of years.

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A change in the position of the magnetosphere during the event could expose the Earth to more cosmic radiation, as well as change the concentration of ozone in the atmosphere. We don’t know when the next reversal might happen, but according to scientific observation, our generation can still sleep easy about it.

source: Noah, nature, European Journal of Physics, US Geological Survey, PTotSA Mathematical, physical and engineering sciences via Conversation