Reversal of Earth's Magnetic Field-(Hey Algore read this)

Projects in Scientific Computing ^ | N/A | Gary Glatzmaier, Los Alamos National Laboratory

[ThreePuttinDude]

Rush made mentioned this week of a core sample that showed evidence of tropical remains from an Arctic sample. Here are the results of a similar study done by a federally funded organization that claims this has been happening for........ever.

Simulated three-dimensional structure of Earth's magnetic field, with inward (blue) and outward (yellow) directed field lines. Field lines extend two Earth radii from the core. The location of the core-mantle boundary is evident where the structure becomes complex

[gondramB]

>>What bullshit. Magnetic compasses have been in use for 600 years and in that time the Earth's magnetic north pole has barely moved. By this "reasoning," magnetic north would have by now moved to Korea.<<

This is established science that the poles reverse. The frequency is in debate.

[RhoTheta]

What bullshit. Magnetic compasses have been in use for 600 years and in that time the Earth's magnetic north pole has barely moved. By this "reasoning," magnetic north would have by now moved to Korea.

My reaction too. We do have to correct Magnetic North to True North (and visa versa), and the correction factor changes enough so that charts don't print the correction factor on them lest they become obsolete. So the field is changing, but massive projections as to when the field will reverse, when the change seems slow, irregular, and un-uniform seems unwise.

[metmom]

Impending doom inded....when the Van Allen belts collapse we will all be fried by intense solar radiation.....enjoy the sun-tan.

Well, according to the medical profession, we'll all be OK if we just use enough sunscreen. SPF 45,000?

[Dog Gone]

See posts 10 and 11.

[Danae]

Nope. This is a real theory. that's why there is a TRUE north and MAGNTEIC north. It's called the Angle of Declination, and it most DEFINATELY changes.


From : http://science.nasa.gov/headlines/y2003/29dec_magneticfield.htm

"Scientists have long known that the magnetic pole moves. James Ross located the pole for the first time in 1831 after an exhausting arctic journey during which his ship got stuck in the ice for four years. No one returned until the next century. In 1904, Roald Amundsen found the pole again and discovered that it had moved--at least 50 km since the days of Ross.


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The pole kept going during the 20th century, north at an average speed of 10 km per year, lately accelerating "to 40 km per year," says Newitt. At this rate it will exit North America and reach Siberia in a few decades.

Keeping track of the north magnetic pole is Newitt's job. "We usually go out and check its location once every few years," he says. "We'll have to make more trips now that it is moving so quickly."

Earth's magnetic field is changing in other ways, too: Compass needles in Africa, for instance, are drifting about 1 degree per decade. And globally the magnetic field has weakened 10% since the 19th century. When this was mentioned by researchers at a recent meeting of the American Geophysical Union, many newspapers carried the story. A typical headline: "Is Earth's magnetic field collapsing?"

Probably not. As remarkable as these changes sound, "they're mild compared to what Earth's magnetic field has done in the past," says University of California professor Gary Glatzmaier.

Sometimes the field completely flips. The north and the south poles swap places. Such reversals, recorded in the magnetism of ancient rocks, are unpredictable. They come at irregular intervals averaging about 300,000 years; the last one was 780,000 years ago. Are we overdue for another? No one knows. "

The magnetic pole is shifting all the time. For my location, in Oregon it is : Declination = 17° 7' E changing by 0° 9' W/year. From the site : http://www.ngdc.noaa.gov/seg/geomag/jsp/struts/calcDeclination
The Field DOES flip. It will happen again. We just have no idea of when it will happen again.

[trickyricky]

"Impending doom inded....when the Van Allen belts collapse
we will all be fried by intense solar radiation.....enjoy the sun-tan"

Calling Admiral Nelson!!!

[ovrtaxt]

Maybe if Michael Moore moved to Tierra Del Fuego, this 1200 year thing would speed up?

[RightWhale]

The compass needle was in use during the Trojan war.

[Strategerist]

I believe during a reversal, worldwide you'd expect eventually several hundred thousand additional human deaths from cancer.

In the grand scheme of things, irrelevant, out of 5 billion people, though it obviously sucks if you're one of the unfortunate several hundred thousand.


There's no evidence of any animals...reptiles, birds, mammals...having mass die-offs during past reversals.

[beethovenfan]

It's that Karl Rove at it again!!

[Salamander]

That was a sarcastic joke.

I always post that pic on junk science/apocalyptic hysteria threads....:)

[Salamander]

"Well, according to the medical profession, we'll all be OK if we just use enough sunscreen. SPF 45,000?"

Oh God.
I'm gonna *really* freckle when it happens.

[Donald Rumsfeld Fan]

To the consternation of our desire to understand what's happening inside the planet we live on, Jules Verne's Journey to the Center of the Earth is still fiction. There's no way to penetrate 4,000 miles to Earth's center, nor to monitor fluid motions or magnetism in the outer core.

[mhx]

Well, according to the medical profession, we'll all be OK if we just use enough sunscreen. SPF 45,000?

I'm just planning to stay inside for the rest of my life.

[RightWhale]

How do we know if the dynamo theory is right?

Earth's mag field is produced by the atmosphere.

[Excellence]

This was the post I was looking for. I was trying to explain this to a guy who said "They have no way to prove the earth is more than 6000 years old." Actually, they do. Thank you so much for posting it.

[Nowhere Man]

Bump for later reading. Ping for possible GGG List

[expatpat]

BS yourself. The long-term changes in magnetic north have been well-documented for decades. Magnetic north is changing as we speak -- just compare some old aeronautical charts with the new versions.

[Veto!]

A year or so ago, PBS ran a very compelling special on the magnetic pole shift, how it happens, how possibilities increase....all with full-color charts and graphs and a very impressive retinue of bigtime scientists at various bigtime universities. I'll see if I cna find a link.

[caveat emptor]

Magnetic compasses have been in use for 600 years and in that time the Earth's magnetic north pole has barely moved.

Magnaetic declination is a phrase familiar to anyone depending on a magnetic compass for route finding or surveying before the advent of GPS. It's the difference between magnetic north and true north. It varies with location and time.

The declination as well as rate of change at point of use needs to be known to get an accurate direction of geographic north. The rate of change may also change. A straightforward explanation with examples can be found here if you're interested.

For more exotic possibilities of "North", see here, here, and here .