A switch in the magnetic poles could affect technology
Scientists say so-called geometric reversals happen a few times every million years or so, and with the last one taking place some 780,000 years ago, researchers fear that the next could be imminent.
When it finally does happen again, the magnetic shield will fail by at least 10 per cent.
With a weakened magnetic shield, the Earth is more vulnerable to solar storms.
Solar storms are caused by radiation which pummels our planet heats up the outer atmosphere, causing it to expand.
The magnetic poles are long overdue a switch
Solar storms: Sun's solar flares light up space
Tue, November 29, 2016
A solar flare is an intense burst of radiation coming from the release of magnetic energy associated with sunspots. Flares are our solar system's largest explosive events. They are seen as bright areas on the sun and last from mere minutes to several hours.
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This means satellite signals would struggle to penetrate the atmosphere, leading to a lack of internet service, GPS navigation, satellite TV such as Sky and mobile phone signal.
Additionally, increased currents in the Earth’s magnetic field – or magnetosphere – could theoretically lead to a surge of electricity in power lines, which can blow out electrical transformers and power stations leading to a temporary loss of electricity in a region.
Phil Livermore, Associate Professor of geophysics, and Jon Mound, Associate Professor of Geophysics, both of the University of Leeds, wrote in an article for the Conversation: “Were this to happen today, the increase in charged particles reaching Earth would result in increased risks for satellites, aviation, and ground-based electrical infrastructure.
Birds use the magnetic poles to navigate
“Geomagnetic storms, driven by the interaction of anomalously large eruptions of solar energy with our magnetic field, give us a foretaste of what we can expect with a weakened magnetic shield.”
Many species of animals, most notably birds, have a sense for the magnetic poles which allow them to successfully navigate the globe during periods of mass-migration, leading experts to fear that it could cause confusion, although as humans were not about during the last switch, it is impossible to accurately predict.
The Earth will be more vulnerable to solar storms
The duo continue: “The simple fact that we are 'overdue' for a full reversal and the fact that Earth’s field is currently decreasing at a rate of 5 per cent per century, has led to suggestions that the field may reverse within the next 2,000 years.
“But pinning down an exact date – at least for now – will be difficult.”
Explaining how it occurs, they add: “Earth’s magnetic field is generated within the liquid core of our planet, by the slow churning of molten iron. Like the atmosphere and oceans, the way in which it moves is governed by the laws of physics.
“A reversal can then be likened to a particular type of storm in the core, where the dynamics – and magnetic field – go haywire (at least for a short while), before settling down again.”