Sentences with phrase «magnetic reversals since»

Not exact matches

Earth's dipole magnetic field strength has decreased 16 percent since 1840 — with most of the decay related to the weakening field in the South Atlantic Anomaly — leading to much speculation that the planet is in the early stages of a field reversal.

And since both sets of rocks contained palaeo - magnetic evidence of the north and south poles» periodical reversals, researchers were able to calibrate the evidence and arrive at an accurate calendar of changing climate conditions, every 405 millennia.