Speculations are rife on the magnetic field reversal of the Earth in the coming years. The planet's magnetic field that acts like an unseen force shields life from harmful solar radiation by shooing away charged particles from the sun has become crucially important for human survival.
Any change in the quantum and location of the magnetic field is expected to unleash many events that may be ecologically and economically costly to human life.
History is replete with events of Earth's magnetic reversals with north and south magnetic poles exchanging places. The anxiety is on how an unfolding polar swap will be affecting life on Earth.
There had been the big ticket and small time reversals of magnetic fields. One type is called excursions, marked by transient and incomplete reversals in which the magnetic poles drift away from the geographic poles, cross the equator only to get back to the previous locations
Reversal In Next 2000 Years?
According to a study, the Earth's field is depleting by 5 percent in a century, suggesting that a reversal is due in another 2,000 years. An exact date is, however, hard to speculate.
Reversals of geomagnetism have occurred a few times with gaps of millions of years though time intervals are hard to trace.
The basic source of Earth's magnetic field is the molten iron boiling down at the core of the planet. The electrons flowing from that fluid lets a magnetic field originate from the electric current as in a giant electromagnet dynamo.
Consequences Of Reversal
The concerns over the consequences of magnetic pole change are compounded by the speculation that such a reversal will reduce the total magnetic power by 10 percent from the current strength. Other scenarios include magnetic poles migrating to the equator and multiple north and south magnetic poles shaping up.
When a heavy alteration in the magnetic field happens under a reversal, the shielding power will suffer and pave way for a surge in radiation at the upper atmosphere of Earth with consequences felt at all levels.
When the magnetic shield weakens, the shower of charged particles on Earth from outer solar regions will intensify and pose high risks to satellites, aviation, and electrical grids at the ground.
Geomagnetic storms are initiated by outbursts of solar energy, which a weakened magnetic field may find hard to resist.
Impact On Modern Life
The consequences of a reversed magnetic field with its corrosion in power can impact the electronic infrastructure on Earth. A bleak scenario can unfold when essential services like electricity, GPS, and the internet go bust and blackouts exasperate economic activity leading to the loss of billions of dollars every day.
There were no modern humans during the full reversal last time. However, mass extinctions have been reported with incidents of high volcanic activity.
Early Stage Of Reversal
Scientists have already observed that Earth's dipole field is declining in terms of its strength as noted in the field intensity surveys held in the mid-nineteenth century. That was deemed a signal that a magnetic reversal is on the anvil.
Nearly 780,000 years have rolled off since the Brunhes-Matuyama reversal. The Laschamp event has been a temporary reversal and took place 41,000 years ago. The change in polarity it induced lasted for around 250 years.
The reversal will hit non-human animal species as well which perceive the gravity through a magnetoreception while supporting themselves in long-distance navigation.
There is still hope as early humans have survived the Laschamp event and life sustained despite reversals as had been recorded in the geological data.