| | Aurora Borealis in Salten, Norway,,,,,,,Link for video included*****could it be a pole flip?
| Monarch
User ID: 613673
 United States
2/12/2009 5:09 PM
Report abusive post | Aurora Borealis in Salten, Norway,,,,,,,Link for video included*****could it be a pole flip?
| Quote |
[link to video.msn.com]
Enjoy :)!
John 3:16 (Amplified Bible)
“For God so greatly loved and dearly prized the world that He [even] gave up His only begotten ([a]unique) Son, so that whoever believes in (trusts in, clings to, relies on) Him shall not perish (come to destruction, be lost) but have eternal (everlasting) life.”
------------------------------------
"They who can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety."-Ben Franklin
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Matthew 7:6
Proverbs 22:3 |
| Anonymous Coward
User ID: 613673 (OP)
United States
2/12/2009 6:00 PM | | Re: Aurora Borealis in Salten, Norway,,,,,,,Link for video included*****could it be a pole flip? | Quote |
[link to news.nationalgeographic.com]
North Magnetic Pole Is Shifting Rapidly Toward Russia
Brian Vastag
for National Geographic News
December 15, 2005
Santa better check his compass, because the North Pole is shifting—the north magnetic pole, that is, not the geographical one.
New research shows the pole moving at rapid clip—25 miles (40 kilometers) a year.
Why Does Earth's Magnetic Field Flip?
Over the past century the pole has moved 685 miles (1,100 kilometers) from Arctic Canada toward Siberia, says Joe Stoner, a paleomagnetist at Oregon State University.
At its current rate the pole could move to Siberia within the next half-century, Stoner said.
"It's moving really fast," he said. "We're seeing something that hasn't happened for at least 500 years."
Stoner presented his team's research at the American Geophysical Union's meeting last week in San Francisco.
Lorne McKee, a geomagnetic scientist at Natural Resources Canada, says that Stoner's data fits his own readings.
"The movement of the pole definitely appears to be accelerating," he said.
Not a Reversal
The shift is likely a normal oscillation of the Earth's magnetic field, Stoner said, and not the beginning of a flip-flop of the north and south magnetic poles, a phenomenon that last occurred 780,000 years ago.
Such reversals have taken place 400 times in the last 330 million years, according to magnetic clues sealed in rocks around the world. Each reversal takes a thousand years or more to complete.
"People like to think something special is happening in their lifetimes, but despite the dramatic changes, I don't see any evidence of it," Stoner said. "It's probably just a normal wandering of the pole."
The north magnetic pole shifts constantly, in loops up to 80 kilometers (50 miles) wide each day.
The recorded location of the pole is really an average of its daily treks, which are driven by fluctuations in solar radiation.
The pole is currently at about 80º north latitude and 104º west longitude, in the Canadian territory of Nunavut.
Importance of the Pole
Pinpointing the precise location of the north magnetic pole is important for navigation: As you move closer to the pole, the direction north indicated by your compass becomes less accurate.
The pole also plays a role in the Northern Lights, which form when solar radiation bounces across the magnetic field in the upper atmosphere. As the north magnetic pole drifts, it will take the Northern Lights with it.
But for scientists, studying the field provides a tantalizing glimpse into the fiery center of the Earth.
The planet's outer core of molten iron spins constantly, acting as a giant dynamo, or electromagnet.
This energy interacts with the rocky mantle of the Earth, which is also shifting, resulting in a complex, ever-changing magnetic field.
"We're close to having a much better understanding on how the field fluxes," Stoner said.
First Reading
The first readings of the north magnetic pole date to 1831, when Sir John Ross and his ship searching for the Northwest Passage became ice-bound.
To pass the time he sent out a team with a compass to take readings, and the team soon found a dipole—an area with compass readings pointing both north and south—in what is now Nunavut. It was the north magnetic pole.
While historical readings date back almost two centuries, Stoner's team wanted to take a deeper look into the past.
They went to the Arctic and pulled 4.5-meter-long (15-foot-long) cores of mud and clay from the bottom of frigid lakes.
Each year, snowmelt deposits a layer of silt at the bottom of the lakes, which is then covered with a layer of clay. "There are these distinct couplets every year," Stoner said. "It's a lot like counting rings in a tree."
Back at his laboratory at Oregon State University, Stoner and his team sliced the cores into thin sections.
They then ran each section through an instrument that reads tiny magnetic particles in the silt to reveal both the direction and intensity of the magnetic field.
Each section comprises five to ten layers, or five to ten year's worth of magnetic readings.
"We can't get down to the yearly scale yet," Stoner said, "but that's getting to be a pretty tight resolution."
In contrast, similar techniques used to measure magnetism in rock have yielded much coarser resolutions of thousands to tens of thousands of years.
Besides recording the movement of the pole, the silt cores also show a recent drop in the strength of the magnetic field, Stoner said, a phenomenon that often accompanies north-south reversals.
But research by French scientists published in 2003 suggests that such "jerks" in the magnetic field—abrupt shifts in intensity and direction—occur often, not just during reversals. |
| Monarch
User ID: 613673
United States
2/12/2009 6:07 PM | | Re: Aurora Borealis in Salten, Norway,,,,,,,Link for video included*****could it be a pole flip? | Quote |
Why Does Earth's Magnetic Field Flip?John Roach
for National Geographic News
September 27, 2004
Earth's magnetic field has flipped many times over the last billion years, according to the geologic record. But only in the past decade have scientists developed and evolved a computer model to demonstrate how these reversals occur.
"We can see reversals in the rocks, but they don't tell us how it happens," said Gary Glatzmaier, an earth scientist and magnetic field expert at the University of California, Santa Cruz.
Based on a set of physics equations that describe what scientists believe are the forces that create and maintain the magnetic field, Glatzmaier and colleague Paul Roberts at the University of California, Los Angeles, created a computer model to simulate the conditions in the Earth's interior.
The computer-generated magnetic field even reverses itself, allowing scientists to examine the process.
Computer Model
Scientists believe Earth's magnetic field is generated deep inside our planet. There, the heat of the Earth's solid inner core churns a liquid outer core composed of iron and nickel. The churning acts like convection, which generates electric currents and, as a result, a magnetic field.
This magnetic field shields most of the habited parts of our planet from charged particles that emanate from space, mainly from the sun. The field deflects the speeding particles toward Earth's Poles.
Our planet's magnetic field reverses about once every 200,000 years on average. However, the time between reversals is highly variable. The last time Earth's magnetic field flipped was 780,000 years ago, according to the geologic record of Earth's polarity.
The information is captured when molten lava erupts onto Earth's crust and hardens, much in the way that iron filings on a piece of cardboard align themselves to the field of a magnet held beneath it.
Most scientists believe our planet's magnetic field is sustained by what's known as the geodynamo. The term describes the theoretical phenomenon believed to generate and maintain Earth's magnetic field. However, there is no way to peer 4,000 miles (6,400 kilometers) into Earth's center to observe the process in action.
That inability spurred Glatzmaier and Roberts to develop their computer model in 1995. Since then, they have continued to refine and evolve the model using ever more sophisticated and faster computers.
The model is essentially a set of equations that describe the physics of the geodynamo. The equations are continually solved, each solution advancing the clock forward about a week. At its longest stretch, the model ran the equivalent of 500,000 years, Glatzmaier said.
By studying the model, the scientists discovered that, as the geodynamo generates new magnetic fields, the new fields usually line up in the direction of the existing magnetic field.
"But once in a while a disturbance will twist the magnetic field in a different direction and induce a little bit of a pole reversal," Glatzmaier said.
These bits of a pole reversal are referred to as instabilities. They constantly occur in the fluid flow of the core, tracking through it like little hurricanes, though at a much slower pace—about one degree of latitude per year.
Typically, instabilities are temporary. But on very rare occasions, conditions are favorable enough that the reversed polarity gets bigger and bigger as the original polarity decays. If this new polarity takes over the entire core, it causes a pole reversal.
"It's a very complicated, chaotic system, and it has a life of its own," Glatzmaier said.
Weak Spot
Peter Olson, a geophysicist at Johns Hopkins University in Baltimore, Maryland, said scientists can now pinpoint the core-mantle boundary where these instabilities in the magnetic field are happening.
One such disturbance Olson has been observing recently formed over the east-central Atlantic Ocean. Like a little hurricane, the anomaly swept toward the Caribbean and is moving up in the direction of North America.
"It's a new one, a little thing," Olson said. "Time will tell whether it develops into something significant. But it is here in the North Atlantic, moving towards the Pentagon. We can track it over the next couple of decades."
Instabilities such as this, Olson added, are causing Earth's magnetic field to weaken. Today the field is about 10 percent weaker than it was when German mathematician Carl Friedrich Gauss first began measuring it in 1845. Some scientists speculate the field is headed for a reversal.
John 3:16 (Amplified Bible)
“For God so greatly loved and dearly prized the world that He [even] gave up His only begotten ([a]unique) Son, so that whoever believes in (trusts in, clings to, relies on) Him shall not perish (come to destruction, be lost) but have eternal (everlasting) life.”
------------------------------------
"They who can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety."-Ben Franklin
------------------------------------
Matthew 7:6
Proverbs 22:3 |
| BadMoonRising
User ID: 611638
 United Kingdom
2/12/2009 6:23 PM | | Re: Aurora Borealis in Salten, Norway,,,,,,,Link for video included*****could it be a pole flip? | Quote |
That's normal for Scandanavia. |
| Anonymous Coward
User ID: 606059
 Sweden
2/12/2009 6:58 PM | | Re: Aurora Borealis in Salten, Norway,,,,,,,Link for video included*****could it be a pole flip? | Quote |
yeah we have them all the time when its cold |
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