North Magnetic Spurt?

We really are confronted with twoquestions.  The first is that it appearsthat the North Magnetic Pole (NMP) is now clipping along at forty miles peryear.  Sustained this means it istravelling at four thousand miles per century and able to swap poles in a millennia.  This is much faster than indicated in thegeological record.  Does such movementhappen in spurts?

The second question is whether weare able to discern such spurts in the geological record by carefulmeasurement?  It seems we should be ableto do so with deep sea cores.

At least we now have a clearindication of how fast the process actually is, and it is certainly within thecorrect parameters.

Once again we get the doubtfultheory about the iron core causing all this. See my posting on the topic by googling this blog under Earth’s MagneticField.  Even without my alternativeexplanation, the iron core idea is rubbish.

Magnetic north shifting by 40 miles a year, might signal pole reversal

The magnetic pole is moving faster than at any time in human history,causing major problems for navigation and migratory wildlife.

By Bryan NelsonMon,Mar 07 2011

POLE POSITION: Magnetic north is moving so fast that it is hamperingnavigation. (Photo:Calsidyrose/Flickr)

The magnetic north pole is currently shifting at a faster rate than atany time in human history — almost 40 miles a year — and some experts believethat it may be the beginning of a complete pole reversal, according to the Independent.

The changes are already beginning to cause major problems for aviation,navigation and migratory animals which use the Earth's magnetic field to orientthemselves. Some airports have even had to change the names of their runways tobetter correspond to their current direction relative to magnetic north.

Ever since the magnetic north pole was first discovered in 1831,geologists have been tracking its progress. Unlike true north (which is markedby the Earth's axis), magnetic north is constantly on the move due to changesin the planet's molten core, which contains iron. Throughout most of recordedhistory, the pole has been positioned at or around Canada'sicy Ellesmere Island, but if it keeps moving at its current rate, it won't belong before it sits above Russiainstead. 

The thing that really makes the pole's current movement so unusual,however, is the speed that it is shifting. In the last decade alone, movementhas increased by a third, throwing off compasses by roughly one degree everyfive years.

Changes that fast have already caused major headaches for the U.S. FederalAviation Administration. Tampa International Airport in Florida has just spenta month renaming all of its runways, which are named after the degree at whichthey point on a compass. Similar changes were recently made to runways at Fort Lauderdale and Palm Beach, and across the country runways now need to berenamed at least once every five years.

The shifting pole may also become a grave concern for migratorywildlife, such asbirds,turtles and other sea creatures which use Earth's magnetic field to navigateover great distances. It's unclear how capable these animals are ofrecalibrating their navigational instincts to compensate for the changes.

The rapid shifting of the pole's position has even prompted someexperts to speculate that the Earth's entire magnetic field may be preparing to"flip," whereby all compasses completely invert and point southinstead of north. It may sound radical, but in geological time, pole reversalsare actually quite common. Though they typically occur once every 400,000 yearsor so, it's been 780,000 years since the last flip.

Scientists disagree about how a pole reversal would effect ecosystemsaround the world, but some alarmists warn of a planet-altering catastrophe,whereby earthquakes and monumental tsunamis threaten the Earth fordecades. Though such radical doomsday prophecies cannot be completelyruled out, the vast majority of scientists are tempered by calmer predictions.

"Reversals typically take about 10,000 years to happen," saidJeffrey Love of the U.S.Geological Survey. "And 10,000 years ago civilisation did not exist. Theseprocesses are slow, and therefore we don't have anything to worry about."

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