A reversal in Earth’s magnetic field thousands of years ago plunged the planet into an environmental crisis that may have resembled “a disaster movie,” scientists recently discovered.
Our planet’s magnetic field is dynamic and, numerous times, it has flipped — when the magnetic North and South Poles swap places. In our electronics-dependent world, such a reversal could seriously disrupt communication networks.
But the impact could be even more serious than that, according to the new study. For the first time, scientists have found evidence that a polar flip could have serious ecological repercussions. Their investigation connects a magnetic field reversal about 42,000 years ago to climate upheaval on a global scale, which caused extinctions and reshaped human behavior.
Earth’s magnetosphere — the magnetic barrier surrounding the planet — originates from the churning of hot, molten metal around its iron core. This perpetually sloshing liquid flow generates electricity that in turn produces magnetic field lines, which curve around the planet from pole to pole, according to NASA.