Magnetic north shifting towards Russia

Polar Shift Inevitable
Sun Mar 6, 2011

Scientists say the magnetic pole, which has been in the icy wilderness of Canada for two centuries, is relocating towards Russia at 40 miles per year.

Surveys show the magnetic north pole is moving faster, threatening everything from the safety of modern transportation systems to the traditional navigation routes of migrating animals.

Scientists say that magnetic north, which for two centuries has been in the icy wilderness of Canada, is currently relocating towards Russia at a rate of about 40 miles a year, reported The Independent.

The speed of its movement has increased by one-third in the past decade, prompting speculation that the field could be about to "flip," causing compasses to invert and point south rather than north, something that happens between three and seven times every million years.

The phenomenon is already causing problems in the field of aviation, added the British daily.

The current rate of the magnetic north's movement away from Canada's Ellesmere Island is throwing out compasses by roughly one degree every five years.

Geologists believe that magnetic north pole (which is different from the true North Pole, the axis on which the Earth spins) moves around due to changes in the planet's molten core, which contains liquid iron. They first located it in 1831, and have been trying to follow its progress ever since.

Records indicate that the pole's location barely moved in the early decades, but in about 1904, it began tracking north-east at a rate of about nine miles a year.

That speed increased significantly from about 1989, possibly because of a "plume" of magnetism deep below ground.

The pole is now believed to be heading towards Siberia at about 37 miles each year.

“Earth's magnetic field is changing in time. And as far as we know, it has always been changing in time," geophysicist Jeffrey Love of the US Geological Survey in Colorado was quoted by the British daily as saying.

Shift of Earth's magnetic north pole affects Tampa airport

(what?--jef)

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 The Tampa Tribune

Published: January 5, 2011

TAMPA - Scientists say the magnetic north pole is moving toward Russia and the fallout has reached -- of all places -- Tampa International Airport.

The airport has closed its primary runway until Jan. 13 to repaint the numeric designators at each end and change taxiway signage to account for the shift in location of the Earth's magnetic north pole.

The closure of the west parallel runway will result in more activity on the east parallel runway and more noise for residential areas of South Tampa.

The busiest runway will be re-designated 19R/1L on aviation charts. It's been 18R/36L, indicating its alignment along the 180-degree approach from the north and the 360-degree approach from the south.

Later this month, the airport's east parallel runway and the seldom used east-west runway will be closed to change signage to their new designations.

The Federal Aviation Administration required the runway designation change to account for what a National Geographic News report described as a gradual shift of the Earth's magnetic pole at nearly 40 miles a year toward Russia because of magnetic changes in the core of the planet.

Earth’s Magnetic Field Flipped Superfast

(there is a school of thought that says it's about to happen again.--jef) 

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* By Alexandra Witze, WIRED Science News
* September 2, 2010 |

Just north of a truck stop along Interstate 80 in Battle Mountain, Nevada, lies evidence that the Earth’s magnetic field once went haywire.

Magnetic minerals in 15-million-year-old rocks appear to preserve a moment when the magnetic north pole was rapidly on its way to becoming the south pole, and vice versa. Such “geomagnetic field reversals” occur every couple hundred thousand years, normally taking about 4,000 years to make the change. The Nevada rocks suggest that this particular switch happened at a remarkably fast clip.

Anyone carrying a compass would have seen its measurements skew by about a degree a week — a flash in geologic time. A paper describing the discovery is slated to appear in Geophysical Research Letters.

It is only the second report of such a speedy change in geomagnetic direction. The first, described in 1995 based on rocks at Steens Mountain, Oregon, has never gained widespread acceptance in the paleomagnetism community. A second example could bolster the theory that reversals really can happen quickly, over the course of years or centuries instead of millennia.

“We’re trying to make the case that [the new work] is another record of a superfast magnetic change,” says lead author Scott Bogue, a geologist at Occidental College in Los Angeles.

Researchers aren’t sure why the geomagnetic field reverses itself. Many think it must have something to do with what creates the field in the first place — convective motions of liquid iron in the planet’s spinning outer core.

Bogue and his colleague, Jonathan Glen of the U.S. Geological Survey in Menlo Park, California, went to Nevada to study a series of well-preserved lava flows. As each flow cooled, it preserved the orientation of the magnetic field at the time, frozen like a tiny compass needle in the rock’s magnetic crystals.

One particular flow caught the scientists’ attention because it seemed to carry a complex magnetic history. This lava, Bogue says, initially started to cool and then was heated again within a year as a fresh lava flow buried it. The fresh lava re-magnetized the crystals within the rock below, causing them to reorient themselves a whopping 53 degrees. At the rate the lava would have cooled, says Bogue, that would mean the magnetic field was changing direction at approximately 1 degree per week.

The Steens Mountain rocks have been reported to preserve a change of 6 degrees per day. That rate was so high — imagine trying to navigate when a compass changes by multiple degrees per day — that many scientists challenged the report. One line of argument held that the liquid outer core simply can’t generate magnetic field changes that rapidly. Another held that, even if the changes were happening, they wouldn’t be observable at the surface because the Earth’s internal electrical conductivity would screen the signals out.

The Nevada rocks bolster the idea that such changes could be happening, says Bogue — even if scientists still can’t explain why.

Not all experts are convinced by the new paper. Dennis Kent, a paleomagnetist at Rutgers University in Piscataway, New Jersey, says it would be “a curious coincidence” to have two brief lava flows just happen to cool and capture a 53-degree change in direction, when reversals happen only a few times per million years.

The last stable reversal occurred 780,000 years ago. Some geologists argue the Earth is overdue for a reversal and might even be entering one now, as the geomagnetic field has been getting weaker over the past 150 years or more.

But apocalyptic SyFy channel movies to the contrary, nobody should worry about waking up one morning to geomagnetic havoc, says Bogue. “To geologists a polarity reversal is a nearly instantaneous thing that changes a global feature of the Earth — it’s really a spectacular phenomenon,” he says. “But if you were alive when it was happening, it probably wouldn’t be that big a deal.”