What causes the Earth’s magnetic poles to shift?

The Earth’s magnetic poles shift due to changes in the flow of molten iron and other metals in the Earth’s outer core. These movements create electric currents that generate the planet’s magnetic field. Over time, the magnetic field undergoes gradual changes, and the magnetic poles can wander, a phenomenon known as geomagnetic secular variation. In some cases, the magnetic poles can even reverse, with the north and south poles swapping places, although such reversals occur over long geological timescales, typically every several hundred thousand years.