ESA observes 15% decline in Earth’s magnetic field, poles are switching gradually
European Space Agency, in a new research, found that our planet is gradually switching its magnetic poles gradually. Studying the reported data, scientists from ESA observed 15 percent decline in Earth’s magnetic field in last 200 years and is shifting at a rate of 5 percent which indicates that a polar flip is on the cards. The flipping of magnetic poles has occurred regularly throughout the Earth’s history. As per the calculations, the last time the magnetic poles flipped was almost 780,000 years ago. The magnetic poles are due for a flip, and this flip occurs within the next 2000 years.
The Earth has two magnetic poles (North pole and South pole) tilted at nearly 22 degrees. These poles are essential as magnetic field lines run between them from north to south outside the Earth and south to north inside the Earth which prevents our planet from harmful cosmic rays. Hence, they have been worried whether this rapid decline could be followed by a flip which could expose us to the devastating radiations from space.
Usually, shifting of the magnetic poles of the earth occurs every 200,000 to 300,000 years, as per ASA. So, it can be said that the full reversal of the earth’s poles is near. This swapping of poles occurs for a temporary basis, and magnetic poles return to their original position. According to ESA, the Earth’s magnetic poles are preparing for a shift and the consequences could be devastating.
When earth’s poles flip, it alters the climate and can also lead to failure of power grids. Also, the flipping of magnetic poles weakens the magnetic field of Earth and this lead to the entry of solar winds as well as electromagnetic radiations into Earth. The scientists have said that over the past 200 years, the earth’s magnetic field has weakened 15 percent. Our earth has actually four poles. Two poles are situated at the top, and the bottom portion of earth, called as North and South Pole. These are called geographic poles. There are other two poles that come from inside the earth’s core known as the geomagnetic poles. The two geomagnetic poles generate the magnetic field for Earth and extend more than 10 Earth radii, or 63.7 million meters, out into space.
As per the ESA, Most of the field is produced at depths greater than 3000 km by the movement of molten iron in the outer core. The rest 6 percent is s partly due to electrical currents in space surrounding Earth, and partly due to magnetised rocks in the upper lithosphere When the scientists looked at the information and satellite imageries collected by ESA’s Swarm Rio satellite they got to know that the north magnetic pole of Earth has shifted in the last 50 years and has caused damage to satellites orbiting right above the South Atlantic owing to the entry of charged particles from Sun and interstellar space. When poles flip or attempt to flip, the earth’s magnetic field weakens, and hence the solar radiations easily reach the earth’s surface. Also, the weakened magnetic field leads to power failure and also affects orbiting satellite.
NASA in a post previously noted, “Scientists understand that Earth’s magnetic field has flipped its polarity many times over the millennia. In other words, if you were alive about 800,000 years ago, and facing what we call north with a magnetic compass in your hand, the needle would point to ‘south.’ This is because a magnetic compass is calibrated based on Earth’s poles.”
“The N-S markings of a compass would be 180 degrees wrong if the polarity of today’s magnetic field were reversed. Many doomsday theorists have tried to take this natural geological occurrence and suggest it could lead to Earth’s destruction. But would there be any dramatic effects? The answer, from the geologic and fossil records we have from hundreds of past magnetic polarity reversals, seems to be NO,” it further noted.
Interesting point to know
In a study appeared in the Geographical research letters, researchers have claimed that Earth was not dipolar in the past and it had more than two magnetic poles, in fact, it had several pairs of magnetic poles.
Earth’s magnetism is due to its core which is made of molten iron. Earth’s core was not solid from the start but it was once molten and later it started to solidify. Researchers from the Carnegie Institution of Science believe that Ancient Earth had multiple poles for some time during the transition.
Scientists wanted to test the magnetic properties of Earth when it had molten core. For the study, researchers examined rocks that had magnetic properties since their formation. Scientists know that Earth was dipolar for nearly 4 billion years, but something happened to its dipolar nature between 0.5 and 1 billion years ago (also known as Neoproterozoic Era).
It was also found that Earth’s core was changing from molten to solid state that created havoc to magnetic field nearly a billion years ago and our planet got several pairs of magnetic poles. However, things started to settle down as the transition phase of core got over and Earth again became dipolar in nature.
“These findings could offer an explanation for the bizarre fluctuations in magnetic field direction seen in the geologic record around 600 to 700 million years ago,” Driscoll added. “And there are widespread implications for such dramatic field changes.”