Talk:North Pole
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[edit] Very very cold!
polar land are always cold because the place is far away from the sun so there is not enofe sun hear.
Not sure if I'm doing this right, but: 'instantaneous pole' is used in this article without being defined or linked to; I would link to it myself, but no such article exists. (and thus I have no idea what it means.)
Where are the editors??? "The North Pole, is very, very cold. It is just a giant piece of ice on top of the world" is just too colloquial! Kemet 13 Dec 2005.
I don't get this (unless there is some legerdemain involved, my compass points north, which is to the north of my current location--how can the pole to the north be a south pole?): Tokerboy
[edit] Magnetic pole
- 1. The north magnetic pole, being the magnetic pole of the Earth's magnetic field. It is so named due to its proximity to the geographic pole, but is in fact a south magnetic pole. (Either that, or every magnet is mislabelled. Magnetic opposites attract, and your magnet "N" points North!)
I saw on a Newton's Apple episode many years ago that what is called the north magnetic pole is in fact the south pole of the earth's magnetic field. This fact was later confirmed by one of my geology professors but I haven't been able to find a printed confirmation from a reputable source. A figure in one of my geology textbooks does show the lines of force for the earth's magnetic field go into the north magnetic pole as if it were actually the south pole of a magnet though. --mav
It was noticed that one end of bar magnets pointed northward long before the reason for this was understood. By convention, the end of the magnet that pointed toward the north was called the "north seeking pole", and over time this is shortened to "north pole". The north-seeking pole of the magnet is being attracted to the south-seeking pole of the earth (opposites poles attract) - which happens to be in the geographic north. Confusing, but there it is. And to make it worse, some magnets are labeled wrong.... -- Someone else 07:23 Dec 30, 2002 (UTC)
- Hm. Interesting. I just hope a magnetic pole shift happens soon to sort this all out. We are a couple hundred thousand years overdue. Just make sure you have plenty of sunscreen since the magnetosphere may not be able to protect us very well for some time afterward (but there is no evidence in the geologic record to suggest that mass extinctions occur during the transitions). --mav
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- I hope it's not as anticlimactic as the millenium...I'll have to order up some fireworks and some Biere de Miele to make the wait worthwhile.... :) --SE
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- It won't sort it out. The current situation is relatively simple. If the Earth's magnetic poles reverse, people will relabel their compasses so that they still point to geographic north. The confusion will be at least an order of magnitude larger :-)
Can someone please explain what the difference is between the magnetic pole and the geomagnetic pole, because they seem exactly the same to me. -- Daran 17:45, 27 Sep 2003 (UTC)
- Belatedly, you get your wish.
- Urhixidur 20:51, 2004 Dec 22 (UTC)
[edit] Astronomical north pole
We claim the following:
Astronomers define the north "geographic" pole of a planet in the solar system by the planetary pole that is in the same ecliptic hemisphere as the Earth's north pole.
This can't be right, because axial tilts greater than 90 degrees would be impossible. NASA defines north pole as follows here:
In astronomy, that end of the axis of rotation of a celestial body at which, when viewed from above, the body appears to rotate in a counter-clockwise direction.
This better matches what I thought the north pole was, and also explains why NASA would list the axial tilts of Uranus and Venus as 98 and 177 degrees, respectively. --P3d0 17:42, Dec 22, 2004 (UTC)
- NASA can do as it wishes, but the IAU definition wins any time. Just goes to show you must be careful to define what you mean when you say something.
- Urhixidur 20:22, 2004 Dec 22 (UTC)
Canadian Sovereignty of the North Pole
Removed this......
Nevertheless, the North Pole of the Earth may be said to be located in Canada. However, recently, Russia and Denmark are poised to contest this point. In the mid-20th Century, Canada made an official claim to the pole; if no compelling opposition is presented by the mid-21st Century, the pole will officially be considered part of Canada.
The sector principle that Canada uses to claim waters to the north pole is very controversial. The United States in particular refuses to accept it and this.
[edit] Santa Claus
About to remove this bit:
- In popular mythology, Santa Claus resides at the geographic North Pole. Canada Post has assigned postal code H0H 0H0 to the North Pole.
It doesn't really fit well with the rest of the article, unless there was enough other material for a proper section on "culture". The place for this information is in the Santa Claus article, but I note that in that article it actually says that "traditions vary".
80.229.160.150 06:57, 30 July 2005 (UTC)
[edit] Dip poles
I just read* that "dip poles" are where the magnetic vector is vertical, and that there are many such points on the Earth. Our article states more than once that magnetic north is where the magnetic vector is vertical. I think our article must be wrong, but I'm not sure yet.
*A Dictionary of Earth Sciences. Ed. Ailsa Allaby and Michael Allaby. Oxford University Press, 1999. Oxford Reference Online. Oxford University Press. --Heron 17:17, 30 August 2005 (UTC)
I suspect that the North and South magnetic poles are defined by fitting as multipole expansion to the magnetic field. The two primary poles would be along the axis of the dipole part. This can be researched in "The Explanatory Supplement to the Astronomical Almanac" [1] - not light reading, however. Pdn 05:16, 31 August 2005 (UTC)
- Thanks. After further reading, I think that the dictionary entry I quoted was too brief to be useful. It could have been trying to say that at any instant there is exactly one northern dip point, but that this point precesses diurnally and drifts on a longer timescale (as this article by a chap from the Canadian National Geomagnetism Program says). The GNP is apparently defined as the place at which the diurnal average dip is 90°. If this is true then it will save me from having to find out what a "multipole expansion" is ;-) --Heron 19:31, 31 August 2005 (UTC)
Good luck, but you piqued my curiosity. I actually am pretty familiar with the reference I cited and gave them many errata for the next edition. That concept from the Canadians may do OK - it may be a matter of opinion, too, and there is confusion between "dip pole" and "dipole!" Be warned that there may be several places of 90 degree dip, and as the Earth field weakens, there may be more. See [2]. But in any case here are a couple of references: [3] [4] which says: "In mid 2002, the average position of the modeled north magnetic dip pole (according to the IGRF-2000 geomagnetic model) is 81.5° N, and 111.4° W, in the Canadian Arctic Ocean. This position is 950 kilometers (590 miles) from the true (geographic) north pole."
Also see [5]
To understand a dipole, you do not really have to go into "multipole expansions". For electricity, the simplest quantity is charge, but if you put two opposite charges near each other you get a dipole. It is an ideal dipole only in the limit that the charges tend to infinity and their separation to zero, because othewise if you look very close, you will see the field of each charge separately, and that's not part of the game. With magnetism, no one has ever found an isolated pole, so the simplest thing (that is known) is a dipole. An example dipole field is shown in [6] although it is messed up with a bar magnet in the middle. The shape of the field lines is correct, though they ought to continue nearer the core. It is hard to find a decent picture because everybody seemingly has played with bar magnets. The material (steel, Alnico or whatever) channels the field to it emerges mostly from two opposite poles, giving an odd shape: [7] That's totally screwed up (because two separated poles are shown). I am getting frustrated trying to find a decent diagram, but you can look at [8]. The upper diagram is wrong, but the lower one (with the black backgound) was evidently drawn from data or by an intelligent person, and it shows the right shape. Out far away, the field lines are distorted by the solar wind, but close to Earth, they are OK - note how much rounder they are than the wrong lines of force shown everywhere. AHA - eureka - NASA got it right: [9]
Anyway, the concept is to fit (approximate) the earth's magnetic field with a dipole field, and then take what is left over and describe it in a more complicated way. That's what I believe the professionals do and your dip poles defined that way will be more stable, as well as there being only one in the southern hemisphere, one north. Pdn 21:46, 31 August 2005 (UTC)
- Thanks for all that! Perhaps our article (particularly the Geomagnetic North Pole section) does contain enough detail, and is correct as far as it goes. --Heron 20:37, 1 September 2005 (UTC)
[edit] Geographic North Pole
In the definition of the above, it states that as one moves away from the pole, one always travels southwards. Clearly this must be so, as the north pole is the earth's northernmost point. However, could it not also be said that one can travel westwards or eastwards from the pole into either the western or eastern hemisphere (defined by the intersection of the pole by the 0 & 180 degree meridians), albeit that there will be also a southwards ('downwards') direction of travel due to the earth's curvature towards the equator? Dillnutt
- No, I wouldn't say that. Leaving the North Pole along a meridian, you always cross lines of constant latitude (parallels) at right-angles, so there is no east-west component to your motion, regardless of which hemisphere you enter. Your direction is pure south. However, your location after your first step would have a longitude associated with it. --Heron 20:07, 7 September 2005 (UTC)
You can see from the entry for polar motion that it is common to refer to motion east or west, etc: (to quote) "The slow westward drift, about 20 m since 1900, is partly due to motions in the Earth's core and mantle, and partly to the redistribution of water mass as the Greenland ice sheet melts, as well as to isostatic rebound, i.e. the slow rise of land that was formerly burdened with ice sheets or glaciers (Munk, 2002). The drift is roughly along the 80th meridian west, towards the eastern part of North America." In this case, the drift is of the geographic pole in relation to the rotational pole, so the "west" is defined in a system aligned with the latter and the displacement westward is plainly visible on the diagrams referenced in the polar motion article. I suppose that if the drift were along a different meridian one might have to specify the meridian, however. Pdn 23:58, 7 September 2005 (UTC)
I corrected the verb-noun agreement in the following sentence: There is no land at this location, which is usually covered by sea ice. The theory under which Canada has claimed sovereignty to the North Pole is controversial as there is in fact 770 km of ocean between the pole and Canada's northernmost land point...
Before it said "there are in fact 770 km of ocean..." The verb is supposed to agree with ocean (singular) not kilometers (plural). You wouldn't say there are three feet of space between here and there, you'd say there is three feet of space. Just picky, I know...[And to please our Canadian friends, I guess I should say "kilometres" not "kilometers" and "one meter" not "three feet"].
[edit] How long is the daylight
Folk lore claims that the North and South poles experience 6 months of day followed by 6 months of night, but a simple experiment with a torch and a globe seems to deny this. What is the true case?
Describe the experiment? Ojw 12:55, 17 September 2005 (UTC)
- It's not folklore, it's fact. See the BBC Weather Centre [10] and the US National Oceanic and Atmospheric Academy [11], for example. Beware of simple experiments. --Heron 17:21, 17 September 2005 (UTC)
[edit] Our "North" Pole is actually the South Pole
Field lines, representing the magnetic flux and created by a magnetic body, travel in a northward direction. This means for a magnetic body the direction to which the field lines are leaving the body represents the magnetic north pole of that body. Our Earth's field lines, if we are correct about the location of our present north pole, should be leaving at the top of our earth and entering where we know our south pole to exist. However, this is not the case. Our field lines actually enter at the location we know as the north pole and leave at the location we know as our south pole. This is would definitely mean, in magnetic terminology, that our north pole is actually a south pole and our south pole, the rightful north pole. Hence, why do we say the wrong thing?
- Our article says that "the Earth's magnetic north is actually a south magnetic pole", which agrees with what you said and is correct. The reason for this is discussed on this talk page, above. --Heron 19:13, 25 April 2006 (UTC)
[edit] question i've always wanted to ask
i know this is kinda stupid but what is the time at the north pole?
i say this as all the time-zones (i assume) meet at the north pole. so if u took a step to the other side of the pole, it may be 6 o'clock, but then u take a couple of steps in another direction, and its 1 o'clock.
Pratj 17:42, 2 September 2006 (UTC)
- Google for "what time is it at the north pole" and you will get as many answers as you want. This post says that "By convention, researchers and others who visit the North Pole tend to use Greenwich Mean Time (GMT)". --Heron 20:17, 2 September 2006 (UTC)
kk, thx.
Pratj 22:10, 2 September 2006 (UTC)
[edit] Various problems with the section "Defining the North Pole of Earth"?
Before I start hacking this around, I'd like to run it past others.
- The article says "The Geographic North Pole, also known as True North, is the basis for the astronomic north pole, which is defined as the point at which the axis of rotation meets the surface of the earth..." I have never heard of the "astronomic north pole" (Google gives no hits other than Wikipedia.) Is there such a thing? I wonder if it is really talking about the Celestial North Pole, but then it's still wrong as this is certainly not "defined as the point at which the axis of rotation meets the surface of the earth".
- Then we have "The Magnetic North Pole is one of the two poles of the Earth's geomagnetic field's dipole moment, specifically the one that is closest to the geographic north pole." I suspect this is muddling with the Geomagnetic North Pole, and that the definition of the Magnetic North Pole later as "the point where the geomagnetic field points vertically downwards" is the correct one.
- Then there is a "definition" of the "Geophysical North Pole" which is apparently "designed to clarify the ambiguity caused by term magnetic north pole", but the explanation does nothing to dispel this ambiguity as it does not tell us what the "Geophysical North Pole" actually is. I have never heard of the "Geophysical North Pole", and again there are no Google hits other than Wikipedia. I wonder if this is another muddle and is supposed to be talking about the Geomagnetic North Pole.
- The definition of "Geomagnetic North Pole" says it is the is the "north end of the axis of the magnetosphere, the geomagnetic field that surrounds earth". While this gives a vague flavour of the meaning, my understanding is that this pole is actually the point of intersection of the earth's surface with the axis of an imaginary magnetic dipole (loosely speaking, a simple bar magnet) that provides a best-fit approximation to the earth's actual (more complex) magnetic field. This concurs with the explanation later. The text then says "Compasses are not affected significantly by this magnetic field" which reads very oddly - as if the earth has two magentic fields, one of which affects compasses and one of which doesn't. I'd be tempted to just remove that sentence.
Any thoughts welcome.
Matt 11:40, 6 September 2006 (UTC).
- I have reworked the intro to read according to my understanding of the definition of these various poles. Matt 21:41, 3 October 2006 (UTC).
[edit] Plaisted/Herbert confusion
In the "Expeditions" section, this article says of Wally Herbert's expedition: "In so doing the team became the first to reach the North Pole by surface travel without the assistance of airlifts." A variety of other sources (e.g. http://www.quarkexpeditions.com/arctic/exploration.shtml and http://members.tripod.com/90north/firstatnorthpole.htm) say that Herbert did rely on air support.
On this evidence I would normally just remove the statement, but now I'm totally confused about the Herbert/Plaisted claims to be the "first" to achieve whatever it was they achieved, and I'm not confident enough about the actual facts to change this stuff. Here are some examples of the confusion:
- http://members.tripod.com/90north/firstatnorthpole.htm says that Plaisted's 1968 claim is "confirmed".
- http://www.northpolewomen.com/History.htm disagrees and says that Herbert's 1969 visit was the "first surface traverse definitely to reach North Pole."
- http://www.thepoles.com/guide/guidenp/history.htm hedges its bets and says "it is believed that the first man reaching the North Pole on surface was instead the American Ralph Plaisted" (my italics).
- The Wally Herbert article says "he became the first man to walk undisputed to the North Pole"
- The Ralph Plaisted article says "Ralph Plaisted made the first confirmed trek to the Geographic North Pole.."
It's all a bit of a muddle. Matt 13:57, 7 October 2006 (UTC).
- See also the comment at Talk:Ralph Plaisted that cites a source claiming Plaisted's attempt to reach the North Pole "ended in failure.". Matt 10:37, 27 October 2006 (UTC).
