Research that shows, Earth’s magnetic field weakening between Africa and South America for no apparent reason and this causing problem for satellites and spacecraft have left scientists perplexed.
Role of the magnetic field
Earth’s field of force is important to life on our planet. It is a mind-boggling and dynamic force that shields us from cosmic radiation and charged particles from the Sun. The magnetic field is generally produced by an expanse of super-heated, whirling fluid iron that makes up the external centre around 3000 km underneath our feet. Earth’s magnetic flux deflects most of the radiations from the sun. These highly charged particles would otherwise rip away the ozonosphere that protects the planet from harmful UV.
Strength dropped by over 8% over the last 5 decades
Scientists studying this phenomenon observed that in recent years, a part referred to as ‘South Atlantic Anomaly’ has grown considerably, though the explanation for this is not entirely clear. Scientists say the area has significantly widened over the past few years at around 20 km per year. What is worrying scientists is that the second area of minimum intensity has emerged southwest of Africa. It is a sign that the South Atlantic Anomaly could break up into two separate cells.
Using data collected by the European Space Agency (ESA) Swarm satellites, scientists state that the area of the anomaly dropped in strength by over 8% between 1970 and 2020 from around 24 000 nanoteslas to 22 000 nanoteslas. ESA mused that chance for the weakening field may be a sign that Earth’s magnetic field is close to reverse. The reversal will cause the North Pole and therefore the South Pole to switch places.
The previous reversal of poles called ‘geomagnetic reversal’ took place 780,000 years ago. Scientists have claimed that such a reversal takes place every 250,000 years and is due since long. Repercussions of such reversal are going to be significant for Earth.
“We are very lucky to possess the Swarm satellites in orbit to research the development of the South Atlantic Anomaly. The challenge now’s to know the processes in Earth’s core driving these changes,” said Jürgen Matzka, German Research Centre for Geosciences.
What will happen if magnetic pole reverses?
Such an event could bring about a significant change. The magnetic field protects Earth from solar winds and harmful cosmic radiations. The magnetic field would also affect Telecommunication and satellite systems and a reversal will disrupt computer systems and mobile phones. The ESA has already warned spacecraft flying in the area ‘South Atlantic Anomaly’ to experience “technical malfunctions”. Also, satellites orbiting the Earth are already facing issues.
A study published in the scientific journal Proceedings of the National Academy of Sciences in 2018, explained that though the process is not instantaneous, it could take many thousands of years to take place.
ESA says it might continue to monitor the weakening field with its constellation of Swarm satellite since the mystery of the origin South Atlantic Anomaly is yet to be solved.
Sources: Independent and thehindubusinessline