Is it really true that ... ... the Poles Change Places?
The magnetic poles have changed places many times. Over the past 20 million years, pole reversal typically took place every 2-300,000 years, but lately, the reversal has been long in coming. Scientists know that about 786,000 years have passed since the most recent pole reversal. If it were possible to travel 800,000 years back in time, the red end of the compass needle would point at the geographic south pole instead of north.
Earth’s magnetic field is believed to be produced around the outer core which consists of molten iron. Due to tiny temperature deviations in the molten mass, convection currents occur, which keep the molten iron in constant motion along with Earth’s rotation. The motion generates an electric current, which induces a magnetic field that sets more of the charged iron moving – a process known as the geodynamo.
In the past 160 years, the magnetic field has been waning, which could indicate that pole reversal is coming up. According to scientists Carlo Laj and Catherine Kissel, it will be in 500 years.