Quick flip of Earth’s magnetic field revealed

April 8, 2004 | Source: NewScientist.com News

The Earth’s magnetic field takes an average of only 7000 years to reverse its polarity, but the switch happens much more quickly near the equator, says study author Bradford Clement of Florida International University in Nature (vol 428, p 637).

Studies of ocean sediments and lava flows show the Earth has undergone several hundred field reversals; the most recent confirmed flip occurred about 780,000 years ago. Evidence published in 2002 suggests that the Earth is now in the first stages of a polarity flip.