Compasses are pointing north ‘for the first time in about 360 years’ in a once-in-a-lifetime event

The Earth’s magnetic field is in a permanent state of change. 

Magnetic north drifts around and every few hundred thousand years the polarity flips so a compass would point south instead of north. 

The strength of the magnetic field also constantly changes and currently it is showing signs of significant weakening. 

Life has existed on the Earth for billions of years, during which there have been many reversals. 

There is no obvious correlation between animal extinctions and those reversals. Likewise, reversal patterns do not have any correlation with human development and evolution.

It appears that some animals, such as whales and some birds use Earth’s magnetic field for migration and direction finding.

Since geomagnetic reversal takes a number of thousands of years, they could well adapt to the changing magnetic environment or develop different methods of navigation.

Radiation at ground level would increase, however, with some estimates suggesting that overall exposure to cosmic radiation would double causing more deaths from cancer. ‘But only slightly,’ said Professor Richard Holme.

‘And much less than lying on the beach in Florida for a day. So if it happened, the protection method would probably be to wear a big floppy hat.’

The movement of the Earth’s magnetic poles are shown in this animation at 10-year intervals from 1970 to 2020. The red and blue lines sjpw the difference between magnetic north and true north depending on where you are standing. On the green line, a compass would point to true north. Credit: NOAA National Centers for Environmental Information

Electric grid collapse from severe solar storms is a major risk. As the magnetic field continues to weaken, scientists are highlighting the importance off-the grid energy systems using renewable energy sources to protect the Earth against a black out. 

‘The very highly charged particles can have a deleterious effect on the satellites and astronauts,’ added Dr Mona Kessel, a Magnetosphere discipline scientist at Nasa.

In one area, there is evidence that a flip is already occurring. ‘The increasing strength of the South Atlantic anomaly, an area of weak field over Brazil, is already a problem,’ said Professor Richard Holme. 

The Earth’s climate could also change. A recent Danish study has found that the earth’s weather has been significantly affected by the planet’s magnetic field.

They claimed that fluctuations in the number of cosmic rays hitting the atmosphere directly alter the amount of cloud covering the planet.

Henrik Svensmark, a weather scientist at the Danish National Space Centre who led the team behind the research, believes that the planet is experiencing a natural period of low cloud cover due to fewer cosmic rays entering the atmosphere.