What actually moves Earth's magnetic north pole?
Show answer & explanation
Answer: Churning liquid iron in the outer core
The Sun's magnetic field tugging on it — Not quite. The Sun's magnetic field, carried by the solar wind, compresses Earth's magnetosphere on the dayside and stretches it into a long tail on the nightside. Those interactions shape the field's outer edge, but they don't reach the deep core where the field is actually generated.
Churning liquid iron in the outer core ✓ — Correct! Earth's magnetic field is generated by convection in the outer core — molten iron swirling about 2,900 km below the surface. When those flows shift, the magnetic pole shifts. The north pole is currently racing from Canada toward Siberia at ~35 km/year, driven by a tug-of-war between field-generating patches deep beneath each region.
Melting polar ice shifting Earth's mass — Not quite. Ice melt does redistribute mass and nudges Earth's rotation axis — the GEOGRAPHIC pole — by centimeters per year. But that's independent of the MAGNETIC pole, which lives thousands of kilometers down in the liquid iron core.
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