Magnetic north pole drifting fast

[Sticks]

The Earth's north magnetic pole is drifting away from North America so fast that it could end up in Siberia within 50 years, scientists have said.



As reported on the BBC website (http://news.bbc.co.uk/1/hi/sci/tech/4520982.stm)

[The Supreme Canuck]

Yep. It even moves a lot in one day (http://gsc.nrcan.gc.ca/geomag/nmp/daily_mvt_nmp_e.php).

Why would the BBC think this is a big deal, I wonder? We've been keeping an eye on it (http://gsc.nrcan.gc.ca/geomag/nmp/northpole_e.php). I think we've got it under control. Don't panic!

;)

[Ken G]

Wait, there's a serious discrepancy in what I get from the data in The Supreme Canuck's link and the BBC claim "The Earth's north magnetic pole is drifting away from North America so fast that it could end up in Siberia within 50 years, scientists have said." Simply put, the magnetic pole moves about a degree in longitude each year, but it is only 8 degrees in latitude away from the pole, and is moving poleward about 0.4 degrees a day! I don't know a lot about curvilinear coordinates, but I know enough to be able to conclude that it will reach the vicinity of the north pole within about half the timeframe they quote, at which point, its westward wander could easily wrap it right back around to our hemisphere. Perhaps the wander is viewed as random, or as part of a great circle, or as part of a much smaller circle whose size would require a long enough baseline to infer curvature. But given that I don't see how one would distinguish these possibilities, I hardly think it reasonable to predict it will ever be in Siberia in the foreseeable future. It is probably just a case of scientists being a little overly dramatic, and the media jumping all over it. Perhaps this is also the reason for The Supreme Canuck's caution that this is really any concern. Not that the magnetic field does all that much, but it does relate to power outages, auroras, and using compasses, so if it really went to Siberia, I think we'd care. Not to mention the international scandal of "stealing" Canada's magnetic pole!

[galacsi]

It is a little strange that the Pole is drifting so fast no ? I believed the earth magnetic filed was producted by convections movement in the nucleus. And these movements are very slow.

[The Supreme Canuck]

From Natural Resources Canada:


What is more, since about 1970 the NMP has accelerated and is now moving at more than 40 km per year. If the NMP maintains its present speed and direction it will reach Siberia in about 50 years. Such an extrapolation is, however, tenuous. It is quite possible that the Pole will veer from its present course, and it is also possible that the pole will slow down sometime in the next half century.

http://gsc.nrcan.gc.ca/geomag/nmp/long_mvt_nmp_e.php

Like I said, we're on top of it. It's just the media sensationalizing things again.

[01101001]

See topic Where is the North Pole Now? (http://www.bautforum.com/showthread.php?t=18898)

[The Supreme Canuck]

Yep. That's where I remembered the site from.

[cyswxman]

Is the magnetic south pole also drifting likewise??

[The Supreme Canuck]

With absolutely nothing but logical inference backing me up, I'm going to say yes. Stands to reason.

[01101001]

With absolutely nothing but supreme confidence in the Aussies, I'm going to say yes.

Australian Antarctic Division: Poles (http://www.aad.gov.au/default.asp?casid=1843)


South Magnetic Pole

The south magnetic pole is not fixed and its position moves about 5 kilometres a year presently in a north to northwesterly direction. The location of the south magnetic pole as at February 1998 was 64.59° S and 138.53° E.

But I bet it's not exactly 180 degrees from the north magnetic pole; it's drift would be similar but not a mirror image match. From a couple samples it looks like the south is moving slower than the north.

[The Supreme Canuck]

Ah, good to know we have someone keeping an eye on the other end of the shop, as it were. ;)

[Maddad]

One thing I find odd is that the first article says the change in magnetic pole position is caused by solar radiation. I had previously thought of it as being determined by geophysical processes within the Earth itself. I did not though have a clear idea of what they might be.

[01101001]

One thing I find odd is that the first article says the change in magnetic pole position is caused by solar radiation.

You mean Daily Movement of the North Magnetic Pole (http://gsc.nrcan.gc.ca/geomag/nmp/daily_mvt_nmp_e.php), I presume.


I had previously thought of it as being determined by geophysical processes within the Earth itself. I did not though have a clear idea of what they might be.

It's discussing the diurnal movement.


The cause of the North Magnetic Pole's diurnal motion is quite different than that of its secular motion.

Those are the little tweaks to the geomagnetic pole's position, from pushes on the field that cause the location of where the field lines are perpidicular to Earth's surface to move slightly.

[novaderrik]

why is this coming out in the "mainstream" media now?
is there a movie coming out next summer about the magnetic poles drifting, thus bringing in a new ice age? or causing the ozonel ayer to disappear, thus causing everyone to get skin cancer and thus causing the extinction of the human race, except for a few scattered survivors that battle over the remaining scraps of civilization?
and is it from the same people that brought us "The Core" or "the Day After Tomorrow"?

[hhEb09'1]

I don't know a lot about curvilinear coordinates, but I know enough to be able to conclude that it will reach the vicinity of the north pole within about half the timeframe they quote, at which point, its westward wander could easily wrap it right back around to our hemisphere. Perhaps the wander is viewed as random, or as part of a great circle, or as part of a much smaller circle whose size would require a long enough baseline to infer curvature. But given that I don't see how one would distinguish these possibilities, I hardly think it reasonable to predict it will ever be in Siberia in the foreseeable future.linear extrapolation :)

Motion on a sphere, given a rate and direction, would follow a great circle. I'm sure that is the approach they took. But there are other perturbations that make it more random. Still, Sticks quote says "it could end up in Siberia". Just look at where it was a hundred years ago, or two hundred.