Earth’s magnetic field is build in the heart of the planet which helps in navigation and solar wind. But what protects us from the dangerous radiation is not stable. The magnetic field changes its direction by exchanging the position of north pole and south pole.
It is not that it is only happening now, scientist says in the distant past, the magnetic field changed it direction every 5 million years. But now it does more often, like every 200,000 years. This proves that the magnetic field is losing its stability. According to a BBC news article, there have 170 magnetic pole reversals in 100 million years and the major one was 781,000 years ago.
Magnetic field is generated by interaction in planet’s core and electrical currents. The bottommost part of the core is the hottest. By means of convection current, the hot iron rises within the core, then sinks by cooling. This is the reason for the variation of magnetic strength and poles reversals.
Swarm constellation’s study with three satellites shows that the magnetic field is getting weakened by 5% every 10 years. They also said that this could be a sign for some major reversal in the future. As the field is weakening ten times faster than predicted, they indicated that even will come very soon.
Evidence of this poles reverse lies in rocks. When the molten rocks cools, its moves towards the field. Geologists observe these and determine the direction of magnetic field.
Although it is unconfirmed by experts what will be the consequences if the magnetic field gets really weak or disappears, it is still not unhighlighted. Magnetic poles’ reversal do interfere with the habit and understanding of migratory animals like sea turtles and birds and they can end up in different places than expected. Furthermore, there are still risk to power grids and communication.