I just dug this out of the "This Week in SCIENCE" emails from
AAAS, from May 12 2006, 312 (5775). The AAAS says: "Not So Fast...The strength of the Earth's magnetic field has decayed since accurate measurements began in 1840, and these changes have led to speculation that the field will disappear or reverse within this millennium."
Which would be pretty scary. We'd either have no north/south poles or our north would become south and vice versa. You can imagine how confusing and dangerous that alone would be... but whjat of electronic gizmos in general and the potential for not just pole reversals but concomitant electromagnetic field disturbance?
Anyway (this was back in May, 2006 remember)they (the researchers, Gubbins et al) have devised a method to use paleointensity measurements in conjunction
with directional information to extend the record of the Earth's magnetic
field back to 1590. Contrary to the recent steep decline, they find that
the dipole moment fell hardly at all until around 1800. So there. It may not be moving so fast after all. Still, it's something to watch.
Labels: dipole decline, environment, magnetic poles