Geomagnetic Pole Reversal

Abstract

Earth's magnetic field is weakening, the north magnetic pole has migrated more than 2,200 kilometers since 1831 and now sits closer to Siberia than Canada, and the South Atlantic Anomaly is deepening and splitting in two — a set of facts that reliably gets misread as the prelude to an imminent flip. This paper develops the physics of the geodynamo, reads the paleomagnetic record, distinguishes excursions from full reversals, and works through the real, debated, and largely fictional consequences of a low-field interval. Its candid probability assessment lands on a deliberately unalarming conclusion: the geodynamo is doing what geodynamos do, the unusual feature of the present moment is our ability to watch it in real time, and resolution sometimes looks like alarm.