What happens if a polar shift occurs

Some people believe global cataclysm will occur when Earth's magnetic poles reverse. When north goes south, they say, the continents will lurch in one direction or the other, triggering massive earthquakes, rapid climate change and species extinctions. The geologic record shows that hundreds of pole reversals have occurred throughout Earth's history; they happen when patches of iron atoms in Earth's liquid outer core become reverse-aligned, like tiny magnets oriented in the opposite direction from those around them.

When the reversed patches grow to the point that they dominate the rest of the core, Earth's overall magnetic field flips. The last reversal happened , years ago during the Stone Age, and indeed there's evidence to suggest the planet may be in the early stages of a pole reversal right now. But should we really fear this event? What will actually happen when north-pointing compasses make a degree turn toward Antarctica?

Will the continents tear themselves apart, or are we in store for much more mundane changes? Earth's magnetic field takes between 1, and 10, years to reverse, and in the process, it greatly diminishes before it re-aligns. According to John Tarduno, professor of geophysics at the University of Rochester, a strong magnetic field helps protect Earth from blasts of radiation from the sun.

With a weak field, this shielding is less efficient. The charged particles bombarding Earth's atmosphere during solar storms would punch holes in Earth's atmosphere, and this could hurt humans. But will they invade your privacy? Go Further. Animals Wild Cities This wild African cat has adapted to life in a big city.

Animals This frog mysteriously re-evolved a full set of teeth. Animals Wild Cities Wild parakeets have taken a liking to London. Animals Wild Cities Morocco has 3 million stray dogs. Meet the people trying to help. Animals Whales eat three times more than previously thought. Environment Planet Possible India bets its energy future on solar—in ways both small and big. Environment As the EU targets emissions cuts, this country has a coal problem.

Paid Content How Hong Kong protects its sea sanctuaries. History Magazine These 3,year-old giants watched over the cemeteries of Sardinia. Magazine How one image captures 21 hours of a volcanic eruption. Science Why it's so hard to treat pain in infants. Science The controversial sale of 'Big John,' the world's largest Triceratops. Science Coronavirus Coverage How antivirals may change the course of the pandemic.

Science Coronavirus Coverage U. Travel A road trip in Burgundy reveals far more than fine wine. The weakened magnetic field allowed more ionising radiation from solar flares and cosmic rays from space to reach Earth. This would have caused extreme weather conditions, including lightning, high temperatures and lots of sunlight — which may have been difficult for organisms to adapt to. Megafauna across Australia and Tasmania — prehistoric giant mammals that existed in the Late Pleistocene — and Neanderthals in Europe went extinct around the same time as the magnetic pole reversal, 42, years ago.

The north pole has been moving spasmodically over the past century, drifting around a kilometre per year, says Cooper. Journal reference: Science , DOI: