North Pole is Leaving Canada

Effect on topo maps by wiredog · 2002-03-20 05:25 · Score: 5, Insightful

Most, if not all, topographic maps have the difference between True north and magnetic north noted on them. This is so that people navigating by compass don't get lost. If the magnetic pole is moving that fast, then the maps are going to have to be updated much more frequently.

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Re:Effect on topo maps by Boulder+Geek · 2002-03-20 05:47 · Score: 5, Informative

This is very old news. The NMP has been known to drift for pretty much as long as there have been compasses. The magnetic declination on topo maps has always been out of date, usually from the moment they've been printed. For example, I've had people tell me that the magnetic declination in the Rocky Mountain Front Range is 17 deg E (based on topos), when in fact it is currently close to 0 (I'm too lazy to look up current coordinates ;-). It may very well have been 17 deg in 1903, but the pole has drifted considerably since then!

The article also makes it clear that the odds are poor that it will actually end up in Siberia, as the pole has never followed a straight line, and the rate of movement has always been unpredictable.

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Re:Effect on topo maps by rehannan · 2002-03-20 06:09 · Score: 4, Insightful

I don't know about you, but I would never go out into the bush without a compass. True, I may also have a handheld GPS unit, but what if it's batteries run out or it falls 200 feet down a rocky slope or I drop it in a lake? For something as important as navigation, never rely on just one device.
Re:Effect on topo maps by Bonker · 2002-03-20 06:09 · Score: 5, Insightful

Who cares about geomagnetic north with the advent of GPS?

Those without electricity to run GPS devices.

Say that you are in a non-urban environment somewhere, either a Boyscout on a trip in the Southwest U.S., a U.S. serviceman in the mountains of Afghanistan, or a deep-sea fisherman off the coast of New England. If you're lucky, you have a GPS device that tells you exactly where you are and what route you should take to get to where you're going. It's certainly safer that way, idn't?

Suppose that your batteries run down, or your generator breaks down, or the GPS device you're using doesn't have a hand crank. I bet you'd really like to know the difference between true north and magnetic north right about then.

Suppose the U.S. goes to war in the near future with a country who is not vastly overwhelmed by our military might. If I was in charge of a war effort in such a country, (China for example, which may happen depending on how we handle the 'War on Terrorism'), I would make a point of using missiles to eliminate the network of GPS sattellites in order to confuse and confound my enemies.

U.S. soldiers, pilots, and ship captains would *have* to care about Magnetic vs. True north at that point. I'm almost certain that standard field gear for all U.S. servicemen still includes a magnetic compass. Any of the Military readers care to confirm or correct me?

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Re:Effect on topo maps by guyo26 · 2002-03-20 08:22 · Score: 4, Insightful

As a former light infantryman in the 10th Mountain Division [you may have heard of them recently] I can say with absoulte conviction that GPS is a hunk of crap.

Yes, we had them, no they were not accurate enough. Several times we took a GPS reading to a KNOWN location. Known as in to 8 digits. For those who don't know what that means, here's a link:
http://www.adtdl.army.mil/cgi-bin/atdl.dll/ fm/3-25 .26/toc.htm

The GPS was consistently off by at least 30 meters. That may not sound like a lot, but when you are calling for direct fire, 30 meters is the difference between wiping out the enemy and wiping out your squad or platoon.

Yes, the lensatic compass is still standard issue: http://www.rangerjoes.com/catalog/selection.cfm?ca tegory=main&id=795

The biggest reason why people wash out of military schools is LandNav [well, and PT I guess]. No combat soldier trusts his luck to a contraption that may/may not be accurate.

Of course this doesn't apply to helicopter pilots and others. And also it doesn't apply to desert regions like Iraq [see Bravo Two Zero for an example of a GPS must]. But for day to day use I'll take my lensatic compass over a GPS in a heartbeat.
Re:Effect on topo maps by GoRK · 2002-03-20 08:25 · Score: 3, Interesting

It should also be noted that the gps signal is fairly weak, and wouldn't be hard to interfere with.

This is a problem which has been all but solved. The military has developed vehicle-mounted gps recievers that can deal with inconceivable amounts of jamming (something about using multiple recievers to filter out the jamming signal - im not a radio expert), then relay the signal over some un-jammed frequency (software-based radio maybe?) to provide highly accurate positioning to weapons and personnel in the field who are unable to recieve the "native" gps signal.

Couple this with the military's ability to selectively introduce faulty data into the GPS signal (and remove it on the ground) and you have a pretty good system for getting you within 10 feet of where you want to go and disorienting your enemy besides.

And in response to the grandparent of this post, good luck hitting any LEO satellite with a missle. That's like trying to shoot a fly at 5000 yards with a .44. Talk about a feat! A more effective anti-satellite weapon would probably be a railgun (a real railgun) capable of hurling millions of particles of dust sized shrapnel at insane speeds in the general vacinity of the target satellite -- if they'd ever finish the development of the weapon..

All that fancy navigational equipment I have in my airplane doesn't come close to approaching the compass/stopwatch/map for reliability.

Ah yes but it certainly does for accuracy and detail!
Re:Effect on topo maps by payslee · 2002-03-20 12:54 · Score: 4, Insightful

To join the objections bandwagon: My biggest issue with GPS is that it doesn't work reliably under tree cover or in canyons, something most manufacturers don't go out of their way to advertise. In the Pacific Northwest, where I do most of my hiking, this means GPS isn't that useful. I mean, it can be sort of fun, and you can download maps and see a little "X marks the spot" right on the trail where you're standing, but I would *never* leave my compass at home.

My favorite example of this was a 4 day outing I did last summer. Two of my friends brought their new GPS toys to play with, and were placing bets on which was better. Due to terrain and heavy tree cover, they were only able to get a reading from one spot the first day. Two spots on the second, and from nowhere (except the parking lot) on the last two days.

Map and compass are easy to master, cheap, always reliable, and weigh less than two ounces. Sure, you can bring your GPS, but I'm still not leaving my compass at home.

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Re:Effect on topo maps by Alsee · 2002-03-21 05:23 · Score: 3, Insightful

The GPS was consistently off by at least 30 meters. That may not sound like a lot, but when you are calling for direct fire, 30 meters is the difference between wiping out the enemy and wiping out your squad or platoon.

...I'll take my lensatic compass over a GPS in a heartbeat.

I'm sure your squad will rest easy knowing you are calling for direct fire based on your compass with better than 30 meters precision.

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Hopefully it slows...... by Ryan_Terry · 2002-03-20 05:30 · Score: 3, Interesting

...or airport painting crews will be staffing up:

Magnetic North Keeps Moving

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that's not bad by laserjet · 2002-03-20 05:32 · Score: 5, Insightful

This is just a natural movement of the pole, that's what it does.

Does anyone else remember from college how the poles just flip every million years or so, and no one really knows why? That whay *I* am worried about. the poles moving just a little bit is fine with me.

but if the poles just flipped, imagine what chaos it would cause. Would we have to relabel all the maps that are made? Many airplanes could not fly (with older instrumentation). Thankfully, GPS should still work..

Here's the main point of the article for those too lazy to click and read:

If the pole follows its present course, it will pass north of Alaska and arrive in Siberia in a half century, but Newitt cautioned that such predictions could prove wrong. "Although it has been moving north or northwest for a hundred years, it is not going to continue in that direction forever. Its speed has increased considerably during the past 25 years, and it could just as easily decrease a few years from now," the geophysicist said. The erratic pole can jump around considerably each day, but migrates on average about 10 kilometers to 40 kilometers each year.

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Re:that's not bad by dattaway · 2002-03-20 05:35 · Score: 3, Funny

Don't worry about the navigational chaos drifting magnetic poles cause, just think what would happen if the North Magnetic Pole ended up on the Equator somewhere.

Would Santa and his elves relocate to Central America? Christmas in Bermuda?
Re:that's not bad by Fweeky · 2002-03-20 05:42 · Score: 4, Insightful

> Does anyone else remember from college how the poles just flip every million years or so

No, that was far too advanced for my college :)

I'm not so bothered by it flipping; I'm bothered by the suggestions that in the process of flipping the field weakens and practically disappears.

It's one thing to think "N is S, and S is now N", it's quite another to think "my compass is useless, and I'm probably going to get cancer from the next solar mass ejection because there's no magnetic field to offset all those high energy particles".
Re:that's not bad by laserjet · 2002-03-20 05:48 · Score: 4, Funny

Hey! I never said I went to a good college!

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Re:that's not bad by gilroy · 2002-03-20 05:50 · Score: 5, Interesting

Blockquoth the poster:

but if the poles just flipped, imagine what chaos it would cause

The orientation of the field doesn't really matter too much. I mean, we'd have to relabel compasses, etc., but no big deal.

But ... during the reversal, the magnetic field actually fades to (essentially) zero, and does so for a noticeable length of time. In that circumstance, the Van Allen Belts disappear and the surface no longer has its usual protection from solar wind, cosmic rays, etc. That's the time to worry.

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Re:that's not bad by Kombat · 2002-03-20 05:54 · Score: 5, Informative

Whoops, guess I should have used the "Preview" button. Corrected post follows:

but if the poles just flipped, imagine what chaos it would cause. Would we have to relabel all the maps that are made?

Aeronautical maps are re-issued every 4-5 years anyway, because of this natural drift. Pick up any aviation chart and look for the curving lines called "deviation lines." These are used by pilots to convert from magnetic heading to true heading. Since the poles move, the lines also move, and the charts are re-printed periodically. This isn't a big deal, since other things change over time too, as new airports are added, and airspace is re-classified.

Incidentally, if the poles flipped, older planes wouldn't have any trouble navigating. All planes have at least a basic instrument navigation system to direct them to fixed radio beacons. Even most older planes are fitted with relatively modern (<10 years old) instrument navigation systems (IFR).

A relatively more significant issue to worry about are the runways themselves. The numbers on the ends of runways are the first two digits of the magnetic heading corresponding to the runway direction. If the poles flipped, these numbers would all have to be updated.

The "chaos" that we'd have to worry about would actually be in relation to the radiation shielding provided by the Earth's magnetic field. If the poles were to switch, it's not the kind of thing that happens instantaneously. It could take years, even decades for the switch to complete, and in the interim, we would be vulnerable to harsh radiation from the Sun. Aside from the obvious effects to our health, this could disrupt power grids and disable magnetic storage media. THAT is what you should be worried about.

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Re:that's not bad by barawn · 2002-03-20 07:59 · Score: 5, Informative

The magnetic field of the Earth is due to a highly spinning core of liquid ferrous material (the "dynamo effect") - that is, sustained electric currents set up a magnetic field. Pole movement and pole reversal are two different things (and probably completely unrelated to each other). What causes pole reversal isn't very well understood - there're some good theories, but until we know more about the inner structure of the Earth, no good solid evidence (the dynamo effect, it should be noted, isn't well understood either! Mars wasn't supposed to have a magnetic field - no liquid core - and Mercury wasn't supposed to have one either - spinning too slow - but they both do, and Mercury's is quite noticeable) as far as I know.

There isn't really a good qualitative description of what's going on, but basically, the core of the Earth is a spinning liquid ferrous object which is highly conducting, and sets up huge currents which produce huge magnetic fields. These magnetic fields can get "trapped" in a convective layer above the core (and become "earthspots", in analogy to "sunspots"). The sunspots act to cancel out the conductive field (the dipole portion) which weakens the field. These perturbations can cause the conductive region to 'flip' to the other polarity (there are two spots of stability, one with + polarity, one with - polarity: if you 'push' the magnetic field enough away from the original, you can shove it to the opposite polarity) which then begins to cause sunspots of its own, and the cycle continues.

The field recovers basically because there are two magnetically generating 'layers' - the core, and the convective region. They, together, cancel each other out, but because the core generates the convective region, the magnetic field is only zero so long as the polarities of the convective region and the core are opposite and equal (which doesn't last 'long' on a cycle scale).

This is all assuming everything works like the Sun does, which is assumed, but not entirely sure. :) The Earth's period is roughly 250,000 years, and the Sun's is 22, so as you can guess, we have a lot of data about the Sun's, and virtually none about the Earth's. :)

I'm moving to Mexico... by Anonymous+Canadian · 2002-03-20 05:32 · Score: 3, Funny

First the Canadian dollar heads south, then the north pole heads north.

Soon enough our beer will start tasting like that weak, watery American beer.

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Take a reasonably uninteresting story... by fruey · 2002-03-20 05:35 · Score: 3, Interesting

...post comments about the conception part, and watch 50% or more of posts go on about their kids being conceived there, shagging in ice and all that.

The CNN article, apart from giving fodder to go on about Arctic Sex, is uninteresting. Nothing scientific about it, just pure, watered down, stretched out simple fact.

You could write it like this:
The North Pole is moving. People might go and look at it. Some even conceive there.

That's it.

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For some values of "many" by maggard · 2002-03-20 05:37 · Score: 4, Interesting

...many couples like to go to the magnetic North Pole to conceive their children

Many?

What - 5, 6? Perhaps a dozen a season? On a planet of 6 billion folks that's "many"? That isn't even a lot compared to any other notable location: How many kids have been conceived within a few km of Niagara Falls by honeymooners? Or what about all of the Asian folks intentionally born in supposedly "lucky" years?

By the way, for only having 200 fulltime inhabitants tourism is a major industry in Resolute Bay with 4 hotels, several charter airline services and a number of tour operators. That the occasional couple decides gave a go at it near the magnetic pole is hardly surprising nor are the numbers unexpected.

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My OnStar in 50 years... by switcha · 2002-03-20 05:39 · Score: 4, Funny

adjust your compass daily

"Hello OnStar, how may I help you Mr. Jones?"

"I think I'm lost. I need to get downtown. Can you tell me where I am?"

"It says you are 10 miles out in the Pacific, Mr. Jones. Do you need assistance?"

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Re:Hm... by gilroy · 2002-03-20 05:40 · Score: 5, Insightful

Blockquoth the poster:

I just wonder what makes people think that the pole is special enough so that they want to conceive their children there.

Magnetic fields, like electric fields, are the modern equivalent of leprechauns, fairies, and demons. For the typical layperson, they are invisible, subtle, and inexplicable. The people going to the North Pole to conceive are the spiritual descendants of those who waited on midsummer's eve in the sacred grove. Since it's something they can't see and don't understand, it must be powerful.

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Re:Moving Magnetic Pole? by Binky+The+Oracle · 2002-03-20 05:42 · Score: 5, Funny

How, exactly, can the North Pole drift northward?

Seems like it would be more accurate to say that Siberia is drifting northward and North America is drifting southward.

WE HAVE TO STOP THIS NOW! At this rate, North America will be South America, environmentalists will be warning about the dangers we face when the Jamaican ice sheets collapse, and Australia will be located somewhere near the moon.

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North Pole Moving? by athakur999 · 2002-03-20 05:56 · Score: 3, Funny

So what, does this mean "Rudolph the Red Nosed Reindeer" is now just "Rudolph the Red"?

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Re:can't blame it by Bob+McCown · 2002-03-20 06:00 · Score: 5, Funny

Maybe it's tired of Canada's 4 seasons:

Almost Winter, Winter, Still Winter, and Highway Construction

Where it's been by Wanker · 2002-03-20 06:01 · Score: 5, Informative

For the more visually inclined, I ran across this plot of the movement of magnetic north since 1831.

Conceived at the North Pole = bad idea by Caractacus+Potts · 2002-03-20 06:45 · Score: 3, Funny

many couples like to go to the magnetic North Pole to conceive their children.

I've met some people who were conceived at the North Pole. None of them seemed to have any direction in life.

Who is to blame? by toupsie · 2002-03-20 07:21 · Score: 4, Funny

This is an outrage! The movement of the magnetic North Pole is no doubt caused by the evil, big business policies of the US Republican Party. Their anti-magnetic stabilization agenda fueled by big time donations from "Special Interest Groups" is another reason that Congress should pass the Campaign Finance Reform bill currently pending. If we are not going to step up to the plate to protect the stability of the Earth's magnetic field, who will? President Bush? Please. We all know he hates the Earth and wants it destroyed today!!!

Join Greenpeace and save the Earth's fragile magnetic stability!!!

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Trying to avoid taxes? by iabervon · 2002-03-20 07:25 · Score: 5, Funny

What do they expect if they keep increasing taxes on magnetic media? The magnetic north pole is obviously going to want to move to somewhere cheaper, like Siberia.

Honk. Honk. by TheFlu · 2002-03-20 07:29 · Score: 3, Funny

So when are geese gonna start flying North for the Winter?

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Isn't it the magnetic south pole? by Florian+Weimer · 2002-03-20 08:07 · Score: 3, Interesting

The compass needle points with its north pole end to the geographic north pole. IIRC, you call this end of the needle its "north pole" and mark it with an "N". Therefore, the magnetic pole in the northern hemisphere has to be a south pole, magnetically speaking.

Re:Isn't it the magnetic south pole? by DunbarTheInept · 2002-03-20 12:42 · Score: 3, Interesting

Actually, the compass is just deliberately mislabelled, I think. It's "N" doesn't mean "this is this the needle's north end", but "this arrow is pointing to the earth's north pole" It's the compass that's labelled backwad. It's easy enough to test - get a magnet labelled as N and S, and hold it up to the compass and see how it gets affected.

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