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Ship Logs Suggest Upcoming Polar Reversal 349

Posted by CowboyNeal from the straight-on-till-morning dept.
Nyerp writes "Researchers are using naval logs dating back as far as 1590 to arrive at better estimates of the decline of Earth's magnetic field. The results suggest that there may be a reversal of earth's magnetic field in about 2000 years." Also worth noting, our ancestors have lived through a number of polar reversals, and we're still here, so no need to fret!
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Ship Logs Suggest Upcoming Polar Reversal More

Ship Logs Suggest Upcoming Polar Reversal

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  • Global Warming? (Score:4, Funny)

    by Anonymous Coward on Saturday May 13, 2006 @11:28AM (#15325042)
    Retroactive due to Global Warming, I bet!

  • Duh. (Score:5, Funny)

    by TubeSteak ( 669689 ) on Saturday May 13, 2006 @11:28AM (#15325044) Journal
    This one's a no-brainer guys.

    Just turn your compass around 180 degrees, then it'll be pointing South instead of North.

    • Re:Duh. (Score:5, Insightful)

      by nsayer ( 86181 ) <nsayer@kfu.cQUOTEom minus punct> on Saturday May 13, 2006 @11:55AM (#15325191) Homepage
      Yes, except that's what you tell your descendents, a few generations after the compass becomes useless.

      While the flips may occur quickly on a geological timeframe, they take much longer than a human lifetime to occur and stabilize.

      A compass is a handy thing to have at sea, since without landmarks its the easiest way to keep pointing in the same direction. But there are other ways to navigate - with and without technology. We (or rather, "they," since we'll long be dust) will just have to make do with them.

      • Re:Duh. (Score:4, Insightful)

        by TubeSteak ( 669689 ) on Saturday May 13, 2006 @12:29PM (#15325385) Journal
        A compass is a handy thing to have at sea, since without landmarks its the easiest way to keep pointing in the same direction. But there are other ways to navigate - with and without technology.
        Like GPS (or the Euro version Galileo) and stars?

        While I doubt mariners will ever stop being taught compass and celestial navigation (tradition is important), I can't imagine either will be needed 100 years from now, much less a thousand.

        Unless those statellites fall out of the sky, GPS is here to stay.

        • GPS to stay? Not necessarily. (Score:4, Informative)

          by emarkp ( 67813 ) <slashdotNO@SPAMroadq.com> on Saturday May 13, 2006 @12:54PM (#15325515) Journal
          As the Earth's magnetic field fluctuates during transition (which we're already seeing), it affects more than the compasses. Our protection from solar radiation substantially decreases as well. Which means that cancers on Earth will go up, but also that satellites will be more likely to fail. So those satellites might just fall out of the sky sooner than you think. Nova had a really good special on the topic a while back, called Magnetic Storm [pbs.org].

        • Re:Duh. (Score:5, Insightful)

          by nsayer ( 86181 ) <nsayer@kfu.cQUOTEom minus punct> on Saturday May 13, 2006 @01:02PM (#15325558) Homepage
          Like GPS (or the Euro version Galileo) and stars?

          No. Neither of those will tell you which way you're pointing. Both of those tell you where you are (actually, the cellestial version will only tell you where you are with the aid of an accurate clock).

          Not quite the same thing.

          On land, it's easy to walk in a straight line. You pick a tree or a rock or a mountain, walk towards it, then check your GPS gizmo and it will tell you which direction you walked. But while you're walking, you simply walk in the direction of the landmark you've chosen.

          At sea, this is impossible. You can't just steer towards a landmark, because there are none. The best you can do is steer towards a particular star (the sun counts), but you'll probably have to make corrections for its motion. A compass serves the same purpose as a distant tree or mountain on land -- keeps you pointing in the same direction over the course of the present to near future. You need to be able to do that reliably before position fixes can help get you where you want to be.

          Position references can be finessed into giving you a bearing track, but that's like telling a day trader that because the stock went up yesterday it's going to go up again tomorrow - maybe, but maybe not. You need more data to be sure.

          • Re:Duh. (Score:5, Informative)

            by Mostly a lurker ( 634878 ) on Saturday May 13, 2006 @01:26PM (#15325668)
            Like GPS (or the Euro version Galileo) and stars?

            No. Neither of those will tell you which way you're pointing. Both of those tell you where you are (actually, the cellestial version will only tell you where you are with the aid of an accurate clock).

            The stars, with even a rudimentary timepiece, are sufficient to provide a good guide to general direction. Before compasses ever existed, navigation was done based on them.

            As for GPS (the most accurate versions) two appliances at opposite ends of a vessel together with suitable calculations would give you the orientation of the vessel. (I have no idea if this is ever done.)

            • Re:Duh. (Score:5, Informative)

              by Spy Hunter ( 317220 ) on Saturday May 13, 2006 @08:22PM (#15327428) Journal
              No need for two GPS receivers. If you are moving, the GPS can easily tell which direction you are going, which is more important than the direction you are facing anyway (especially on a boat or plane where they might be different without an easy way to tell).
          • Both of those tell you where you are (actually, the cellestial version will only tell you where you are with the aid of an accurate clock).

            Polar, or circumpolar stars can tell you the direction of the pole, and from there you can infer your approximate heading fairly easily.

            Polaris (in the northern hemisphere) and a small trick using the southern cross and pointers in the southern hemisphere do the job ok.
        • Kinda handy if your batteries go dead or you drop your GPS.

          Ask any pilot or sailor if they'd fly or leave sight of land with only GPS. You always have a compass, and should be able to at least find the north star if THAT breaks.

      • Re:Duh. (Score:3, Interesting)

        by rbochan ( 827946 )
        "I must go down to the seas again,
        to the lonely sea and the sky,
        And all I ask is a tallship,
        and a star to sail her by,..."
              --John Masefield

        There were sucessful sailors long before there were compasses...
        And there's always those new fangled gps thingies.

      • Compasses would still work during the actual flip. There will still be a residual magnetic field while the flip is happening (but only about 10% as strong it is today)it would only be when the new reversed magnetic firld strengthens to the point to eaqual the residual field that compasses will not work,however this period of time will be much shorter than the switch itself as the reverse field would continue to strengthen. (your looking at about 10-20 years with the total magnetic field at 1% of todays if

  • electronic dependence (Score:4, Insightful)

    by pilybaby ( 638883 ) on Saturday May 13, 2006 @11:29AM (#15325048)
    Our ancestors may have lived through this several times before but wont it affect us more as we are highly dependent on electricity and satalites etc?
    • Our ancestors may have lived through this several times before but wont it affect us more as we are highly dependent on electricity and satalites etc?

      And then they say movies have no bad effect on youth...

    • Re:electronic dependence (Score:5, Funny)

      by Sponge Bath ( 413667 ) on Saturday May 13, 2006 @12:00PM (#15325223)
      ...affect us more as we are highly dependent on electricity

      It won't affect my stereo because I'm using Monster
      brand cables with a special anti polar reversal coating.
      The extended warranty I was sold should keep it
      functional for the 2000 years it takes to complete the process.

      Man, Best Buy rocks!

      • I'm using Monster brand cables...

        It won't affect you because after you've paid the over-priced tariff for those cables you can't afford electricity at these rapidly rising rates anyway.

        Circuit City tried to sell my mother those $70 connectors with her new 37" Sharp TV, along with a $85 Super Surge Protector. Both, she was told, were essential to the full operation of her new television. Fortunately she said no to that, although the TV has HDMI sans HDCP - which they conveniently neglected to mention.

    • we are highly dependent on electricity and satalites etc?
      and not to forget spellcheckers

    • Affect US? (Score:2, Insightful)

      by skayell ( 921119 )
      I do not think it's going to affect me personally at all? Why are you worried?
    • Not only that, but probably many people *didn't* live through it due to the insane rates of skin cancer.
      • Call me crazy, but didn't people have a short enough expected life span back then that, on average, it wouldn't be a problem?

        Hmmm... Then again, could our thing about not going outside without clothing be a remnent of the last reversal? ;)

  • long term effects (Score:4, Insightful)

    by adolfojp ( 730818 ) on Saturday May 13, 2006 @11:29AM (#15325049)
    If this slow reversal is happening as we speak; what effect could it have on bird migration and magnetotactic bacteria?

    • Re:long term effects (Score:5, Funny)

      by BigCheese ( 47608 ) <dennis.hostetler@gmail.com> on Saturday May 13, 2006 @11:39AM (#15325098) Homepage Journal
      That will be interesting to see. They probably have a mechanism for handling it since it happens periodically.
      I'm sure the biggest result of magnetic field reversal will be the number of PhDs granted.
    • Not sure. But we do know that Earth First! will blame the problem on humanity.
    • Birds in the southern hemisphere already fly north for the winter.
      That should tell you more than anything about birds:

      They prefer to be warm and they don't give a damn about the magnetic pole.

      (actually, you would probably confuse some birds, but its the warmth they are seeking, not a compass bearing)

  • Yei! (Score:5, Funny)

    by suv4x4 ( 956391 ) on Saturday May 13, 2006 @11:30AM (#15325053)
    The results suggest that there may be a reversal of earth's magnetic field in about 2000 years.

    Let the War on Polar Reversal begin!

  • Imagine the customers.... (Score:5, Funny)

    by MindPrison ( 864299 ) on Saturday May 13, 2006 @11:33AM (#15325065) Journal
    ...faces when they return to the shop to complain about their compasses showing the wrong direction.
    • Compasses are broken now. The north pole of a magnet should point toward the south pole of the planet and vise-versa.
    • That's why it's called "Mother Earth"; it keeps changing it's mind about which way to go.
    • Remember we're talking about "geological time" not "web time", so big changes like this happen a lot slower. According to Wikipedia:
      "At present, the overall geomagnetic field is becoming weaker at a rate which would, if it continues, cause the dipole field to temporarily collapse by 3000-4000 AD."

      So it'll be a bit of time before that happens. If I understand it correctly, it'll slowly get weaker and weaker until it just disappears before slowly coming back on the flip side. Hopefully the slowness will give

  • north = ? (Score:3, Insightful)

    by novastar123 ( 540269 ) <chris.claus42@gmai l . c om> on Saturday May 13, 2006 @11:33AM (#15325068)
    Does this mean that for a while, depending on how long it takes for the field to reverse that there will be no north or south magnetic pole?

    • Re:north = ? (Score:5, Informative)

      by Anonymous Coward on Saturday May 13, 2006 @12:23PM (#15325348)
      Not entirely. There will actually be several poles.

      The Earth's magnetic field isn't just a dipole (2 pole) field. There are other components of the field, quadurpole (4 pole), octopole (8 pole), etc.. Normally, these components are at least on oder of magnitude weaker than the dipole component. During a magnetic field reversal, the dipole component is so weak that the other components become important. The Earth will then have several sets of weak magnetic poles, at various places around the Earth.

  • Slightly off... (Score:3, Interesting)

    by Justifiable_Delusion ( 759339 ) on Saturday May 13, 2006 @11:34AM (#15325070) Homepage
    To say just because our ancestors lived through it 780 million years ago does NOT mean that we will do just fine and shouldn't fret. Maybe something like this occuring leads to accelerated mutations and changes in the human genome (or all animals for that reason). I would like to see if there were any studies done looking at genetics before and after each of these flips in the general population of living things. The planets surface is BATHED is radiation. To think this would have no affect on us would be foolish. We will have to change the way we live. Skin cancer now a days is bad enough....imagine multiplying it by a factor of 10,000.

    SPF my ass.
    • That's a good point. Geomagnetic reversal is actually a relatively poorly understood phenomenon http://en.wikipedia.org/wiki/Geomagnetic_reversal [wikipedia.org] and it's hard to predict exactly what would happen.

      I suppose there are a lot of scientists who'd be delighted to see one take place - it'd be the first chance to study the phenomenon up close.

    • Re:Slightly off... (Score:5, Informative)

      by 4D6963 ( 933028 ) on Saturday May 13, 2006 @12:07PM (#15325276)
      To say just because our ancestors lived through it 780 million years

      780 million years ago, there was nothing close to a monkey on earth. There wasn't even any ammonites IIRC. I think you mean 780,000 years ago.

      As for your skin cancer concern, I saw a show about the very topic of magnetic field reversal on TV about one year ago. They explained basically what this article explains about the field weakening and all that, and they answered to the question of whether cancers due to the the lack of a magnetic field would wipe all of us out of the surface of us, and the answer was that the number of cancers due to that wouldn't be that significant, however I forgot the estimates.

      • seriously, there's only a few viable scenarios here:
        *we all kill ourselves off long before that through some kind of global warfare
        * we are reduced to a scattering of stone age civilizations from said warfare
        * we don't have said warfare, and aliens make contact in the meantime, and we're all enslaved or otherwise screwed (for anyone who doesn't think we'll be getting f'ed in the A if aliens show up, here's a quarter, buy a clue.)
        * we survive any or all of the above, and manage to colonize other worlds (prob
    • I guess what I'm curious about, is how animals (birds come to mind first) will deal with their reliance on magnetic fields. Has anyone done any studies on whether or not migratory bird can evolve quiclky enough to adapt to the modified magnetic fields. Is their "compass synchronization" that seens innate, a matter of what they cue into when they're born and growing up, or an evoluationary thing. It's hard to imagine evolution (which takes millions of years to adapt) keeping up with such a short term magn
    • You can do a google search for "Great lakes" "nuclear event",

      TERRESTRIAL EVIDENCE OF A NUCLEAR CATASTROPHE IN PALEOINDIAN TIMES [uga.edu]

      There seems to be a supernova event that actually managed to heat the atmosphere to 1000C, melt glaciers and possibly cook large mammals as well.

    • Re:Slightly off... (Score:5, Interesting)

      by ceoyoyo ( 59147 ) on Saturday May 13, 2006 @03:04PM (#15326106)
      Not quite. Skin cancer is believed to be caused by UV radiation. The magnetic field has absolutely no effect on UV. What the magnetic field DOES help to block is charged particles, particularly protons.

      People living at high latitudes and on the equator or flying planes for a living already get quite a bit more proton radiation than everybody else. British Airways has monitored their flight crews for a couple of decades and found that, despite the higher exposure, life expectancy was higher and cancer rates lower.

    • Re:Slightly off... (Score:3, Informative)

      by Decaff ( 42676 )
      Maybe something like this occuring leads to accelerated mutations and changes in the human genome (or all animals for that reason).

      This is extremely unlikely. We probably get most of our protection from solar and cosmic radiation from the atmosphere, not from the magnetic field. There may be minor ground-level radiation increases during a reveral, but probably nothing signficant. The most significant effect will be spectacular aurorae all the way to the equator!

      Significant areas around the poles are not
  • I hear the penguins call it the War of Northern Aggression.

  • Earths shielding? (Score:3, Insightful)

    by jupiter909 ( 786596 ) on Saturday May 13, 2006 @11:41AM (#15325109)
    How does all this relate to the Earths field saving us from being turned into toast from the Sun's and other harmful effects. Do we go into a stage of danger and then end up being safe again once the field is reversed? They do not make mention of this. I know that a few solar flares and computers and power grids can go down when Earth can't deflect it. With it growing weaker are we now at great risk?

    Lots of questions, I need answers.
    • How does all this relate to the Earths field saving us from being turned into toast from the Sun's and other harmful effects. Do we go into a stage of danger and then end up being safe again once the field is reversed? They do not make mention of this. I know that a few solar flares and computers and power grids can go down when Earth can't deflect it. With it growing weaker are we now at great risk?

      The Sun's magnetic field reverses every eleven years. It's the relative orientation of the solar and terrest

  • "No need to fret?" Like hell. (Score:5, Interesting)

    by gblues ( 90260 ) on Saturday May 13, 2006 @11:41AM (#15325113)
    Also worth noting, our ancestors have lived through a number of polar reversals, and we're still here, so no need to fret!

    Sure, no need to fret. It's not like we haven't invested hundreds of years worth of technology and research based on magnetic reference points. Oh, wait...

    Nathan

  • It's just... (Score:5, Funny)

    by Anonymous Coward on Saturday May 13, 2006 @11:41AM (#15325116)
    It's just the Earth's way of trying to degauss itself ... just not doing a very good job of it so far!

  • Commercials (Score:2, Insightful)

    by ericartman ( 955413 )
    How long till the first infomercial offering "Kits" to protect us from the upcoming polar reversal?

  • Have you seen maps from 1590? (Score:5, Funny)

    by Anonymous Coward on Saturday May 13, 2006 @12:06PM (#15325269)
    According to those maps, the world was a different shape, and had huge monsters in the oceans.
  • Why would I fret over returning to the state of civilization 780,000 years ago?

  • Cause for concern (Score:5, Funny)

    by cmeans ( 81143 ) * <chris DOT a DOT means AT gmail DOT com> on Saturday May 13, 2006 @12:14PM (#15325310) Journal
    I think it's safe to say that everyone that was alive during the last reversal, is dead now.

    I find it hard to believe that we shouldn't be concerned.

  • North will stay the same... (Score:5, Funny)

    by LinuxRulz ( 678500 ) on Saturday May 13, 2006 @12:14PM (#15325312)
    as long as the toilets in the northern hemisphere still flush clockwise.
  • "Antenna Web", so there "Compass Orientation" reflects the change in declination.

  • Need to Take Action Now (Score:4, Funny)

    by Nom du Keyboard ( 633989 ) on Saturday May 13, 2006 @12:34PM (#15325415)
    there may be a reversal of earth's magnetic field in about 2000 years.

    There's clearly a need to take action now. I'd better go clear my calendar, then I'll be prepared.

    Memo to Self: Get stick on "N" and "S" labels for compass.

  • I hope sailors and explorers remember how to use astrolabes and sextants.

  • reader grabbing (Score:2, Interesting)

    by suv4x4 ( 956391 )
    Did you notice how the title speaks about "upcoming" reversal and the article about "reversal in 2000 yr".. I don't know about you, but upcoming for me would mean at least while I'm ALIVE, no?
  • They also suggest a disturbing severe shortage of women, and a high increase in the consumption of 'hardtack.'
  • Does this mean Santa Claus will have to move?
  • We're already seeing a rapid shift from geomagnetic references to inertial and satellite references in navigation. 2,000 years from now, it's unlikely magnetic compasses will be anything but a novelty.
  • I would like to know what evidence there is that there ever was a magnetic reversal. Check out this page from a book by Walt Brown [creationscience.com]. There is a section about this a little over halfway down the page under the section called Magnetic Variations on the Ocean Floor. I think this is where people come up with the notion of past reversals, but there is no true evidence.
  • Think of all those poor Orienteers, wandering around but never finding the flag...

    2000 years, huh? Congress better get to work on this right away - that seems like about the right timeframe for them.

  • Less strange than fiction (Score:3, Interesting)

    by haelduksf ( 812679 ) on Saturday May 13, 2006 @02:27PM (#15325932)
    There's an excellent novel by N. Lee Wood called Faraday's Orphans [amazon.com] set in the apocalyptic aftermath of just such a reversal. Probably inaccurate, but interesting.

  • It's about time! (Score:3, Funny)

    by FridayBob ( 619244 ) on Saturday May 13, 2006 @02:59PM (#15326080)
    As far as I'm concerned, I've just about had it with the fact that the geographic north pole is where the magnetic south pole is. It's damned confusing! I say we change things right away: the sooner the poles are in the right place, the better!

  • Solution: Solar wind is going to create a new MF! (Score:3, Interesting)

    by mha ( 1305 ) on Saturday May 13, 2006 @03:35PM (#15326247) Homepage
    I read this story in a German magazine a few days ago (http://www.spiegel.de/wissenschaft/weltraum/0,151 8,300232,00.html). They pointed to a an article about a study (http://xxx.uni-augsburg.de/abs/astro-ph/0404580) that says simulations of a complete failure of the earths mag. field is going to lead to a complete replacement by a new mag. field - created by the charged particles of the solar wind when they encounter the upper parts of the earths atmposphere. They also point out that this simulation seems credible because nowhere could anyone find any signs of mass extinctions or even mass mutations the many times the earths m.f. reversed so far.

  • Global Warming (Score:3, Interesting)

    by cmarkn ( 31706 ) on Saturday May 13, 2006 @03:38PM (#15326264)
    The timing of these measurements is interesting, in that the date when the magnetic field began to fall is about the same time as the global temperature began to climb. Although I wouldn't dare suggest a mechanism for the relationship, it appears possible that there is one: and it is even mentioned in the article - as the magnetic field weakens, less solar radiation is deflected. What isn't mentioned is that as more radiation hits Earth, the warmer it gets. This relationship is certainly something worth investigating.

  • Yes we survived (Score:3, Interesting)

    by Danathar ( 267989 ) on Sunday May 14, 2006 @07:10AM (#15329098) Journal
    But the real question is what percentage of people DIED!

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