This sounds like the plot for a disaster movie: an invisible magnetic force-field that defends life on Earth against killer rays from space goes awry. Blasts of radiation destroy our satellite communications and bring the world’s electricity supplies crashing down.
Chaos reigns. Human cancer cases multiply as unshielded radiation from the sun devastates people’s DNA. Billions of creatures the world over die because their ability to migrate becomes fatally confused by changes in our planet’s magnetic field.
Ultimately, Earth’s atmosphere itself could be blown away by fierce solar winds, as happened long ago to our sister planet Mars when its magnetic field dissipated.
But hold the popcorn. This is not a sci-fi movie. Leading scientists warn that this may really happen, because of an imminent revolution at the Earth’s core.
High-tech monitoring equipment is showing multiple signs that the Earth’s magnetic poles are about to flip, thanks to changes in the swirling iron core at the heart of our planet.
If this happens, Earth’s magnetic field will literally turn upside down.
During the thousand years it will take for this change to complete, our vital protective magnetic shield will become significantly weaker — with potentially disastrous consequences.
Scientists predict that it could wither to as little as a tenth of its usual force, radically diminishing Earth’s defence against radiation and streams of charged energy particles called the solar wind.
Evidence from ancient rocks indicates that this reversal in the world’s magnetic field has occurred hundreds of times in our planet’s long history. Beneath Earth’s solid crust is a rolling layer of liquid iron kept molten by heat escaping from the planet’s core. The swirling currents of this mass of metal act as a gigantic electromagnet.
This creates a force field that expands tens of thousands of miles into space and acts as an energy shield against viciously powerful radiation from the sun. All life on Earth depends on this shield. Without it, solar rays would simply rip apart the fragile DNA that creates animals and plants.
These liquid-iron currents beneath our feet are not stable.
Over millennia the electromagnetic field they create can completely reverse itself.
The process is believed to take several centuries — an age in human terms, but the blink of an eye in cosmic time.
Evidence indicates that the next reversal is already under way. Earth’s magnetic shield is currently weakening ten times faster than previously thought, at 5 per cent per decade, according to satellite data gathered by the European Space Agency (ESA).
The magnetic field is particularly weakening over South America, an area that scientists call the South Atlantic anomaly. Satellites flying over this area have already had their circuits frazzled by localised radiation spikes.
Data from ESA monitoring has also revealed ‘restless activity’ in the liquid iron currents beneath Earth’s surface, which suggests the field could be about to flip.
SOURCE: JOHN NAISH