The Earth has a fierce molten core that generates a magnetic field capable of defending our planet against devastating solar winds.
The protective field extends thousands of miles into space and its magnetism affects everything from global communication to power grids.
But this magnetic field, so important to life on Earth, has weakened by 15 per cent over the last 200 years.
And this, scientists claim, could be a sign that the Earth’s poles are about to flip.
In a new report, Daniel Baker, director of the Laboratory for Atmospheric and Space Physics at the University of Colorado, Boulder, claims there are signs of a reversal.
He says if this reversal happens, it is likely to render some areas of the planet ‘uninhabitable’ by knocking out power grids.
His comments were made in an in-depth Undark report written by Alanna Mitchell, who has a new book about the topic titled ‘The Spinning Magnet: The Electromagnetic Force that Created the Modern World and Could Destroy It’,
Mitchell writes: ‘The dangers: devastating streams of particles from the sun, galactic cosmic rays, and enhanced ultraviolet B rays from a radiation-damaged ozone layer, to name just a few of the invisible forces that could harm or kill living creatures.’
Historically, Earth’s North and South magnetic poles have flipped every 200,000 or 300,000 years.
However a flip is currently overdue as the last one was about 780,000 year ago.
The latest satellite data, from the European Space Agency’s Swarm trio which monitors the Earth’s magnetic field, suggests a flip may be imminent.
The satellites allow researchers to study changes building at the Earth’s core, where the magnetic field is generated.
Their observations suggest molten iron and nickel are draining energy out of the Earth’s core near where the magnetic field is generated.
While scientists aren’t sure why exactly this happens, they describe it as a ‘restless activity’ that suggests the magnetic field is preparing to flip.
If a switch happens, we would be exposed to solar winds capable of punching holes into the ozone layer.
The impact could be devastating for mankind, knocking out power grids, radically changing Earth’s climate and driving up rates of cancer.
‘This is serious business’, Richard Holme, Professor of Earth, Ocean and Ecological Sciences at Liverpool University told MailOnline.
‘Imagine for a moment your electrical power supply was knocked out for a few months – very little works without electricity these days.’
The Earth’s climate would change drastically. In fact, a Danish study believes global warming is directly related to the magnetic field rather than CO2 emissions.
The study claimed that the planet is experiencing a natural period of low cloud cover due to fewer cosmic rays entering the atmosphere.
Radiation at ground level would also increase, with some estimates suggesting overall exposure to cosmic radiation would double causing more deaths from cancer.
Researchers predict that in the event of a flip, every year a hundred thousand people would die from the increased levels of space radiation.
‘Radiation could be 3-5 times greater than that from the man-made ozone holes. Furthermore, the ozone holes would be larger and longer-lived,’ said Dr Colin Forsyth from the Mullard Space Science Laboratory at UCL.
The magnetosphere is a large area around the Earth produced by the planet’s magnetic field.
Its presence means that charged particles of the solar wind are unable to cross the magnetic field lines and are deflected around the Earth.
Scientists have discovered that ancient pots can act as a magnetic time capsule.
This is because they contain an iron-based mineral called magnetite. When pots form, the magnetite minerals align with the Earth’s magnetic field, just like compass needles.
By examining pottery from prehistory to modern times, scientists have discovered just how dramatically the field has changed in the last few centuries.
They’ve found that Earth’s magnetic field is in a permanent state of flux.
Magnetic north drifts and every few hundred thousand years the polarity flips so a compass would point south instead of north.
If the magnetic field continues to decline, over billions of years, Earth could end up like Mars – a once oceanic world that has become a dry, barren planet incapable of supporting life.
But scientists claim the rate of decline is too fast for the Earth’s core to simply burn out.
Instead, the story told by ancient pottery suggests the Earth’s poles could be about to undergo another flip.
According to the British Geological Survey, the Earth’s magnetic field has on average four or five reversals in polarity every million years and we’re now overdue a similar event.
‘At the moment, we cannot accurately determine whether or not the Earth’s field is about to flip,’ said Dr Forsyth. ‘We have only been recording the Earth’s field for around 170 years; about 1-15 per cent of the time a flip is expected to take.’
If a flip occurs, it would cause the Earth’s magnetic shield to be weakened for thousands of years, opening up our defences and causing cosmic radiation to get through.
‘We have a double layer defence shield,’ said Jim Wild a space scientists at Lancaster University.
‘Space is full ofstuff that’s not great for biological tissue. If we didn’t have an atmosphere,that stuff would be hitting us. It’s the magnetic field protects atmospherefrom the solar wind.’
