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Ship Logs Suggest Upcoming Polar Reversal

Posted by ryuzaki0 on 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!

35 of 349 comments (clear)

  1. Global Warming? by Anonymous Coward · · Score: 4, Funny

    Retroactive due to Global Warming, I bet!

    1. Re:Global Warming? by Jedi+Alec · · Score: 5, Funny

      Nah, this is just God's way of telling us to bring back Star Trek. Oh noes, something's broken, reverse the polarity!

      --

      People replying to my sig annoy me. That's why I change it all the time.
  2. Duh. by TubeSteak · · Score: 4, Funny

    This one's a no-brainer guys.

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

    --
    [Fuck Beta]
    o0t!
    1. Re:Duh. by nsayer · · Score: 4, Insightful

      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.

    2. Re:Duh. by TubeSteak · · Score: 3, Insightful
      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.
      --
      [Fuck Beta]
      o0t!
    3. Re:Duh. by nsayer · · Score: 4, Insightful
      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.

    4. Re:Duh. by Mostly+a+lurker · · Score: 4, Informative
      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.)

    5. Re:Duh. by Spy+Hunter · · Score: 4, Informative

      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).

      --
      main(c,r){for(r=32;r;) printf(++c>31?c=!r--,"\n":c<r?" ":~c&r?" `":" #");}
  3. electronic dependence by pilybaby · · Score: 4, Insightful

    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?

    1. Re:electronic dependence by Sponge+Bath · · Score: 5, Funny
      ...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!

  4. long term effects by adolfojp · · Score: 3, Insightful

    If this slow reversal is happening as we speak; what effect could it have on bird migration and magnetotactic bacteria?

    1. Re:long term effects by BigCheese · · Score: 5, Funny

      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.

      --
      The obscure we see eventually. The completely obvious, it seems, takes longer. - Edward R. Murrow
    2. Re:long term effects by ultranova · · Score: 3, Funny

      I'm sure many individual birds will get screwed, and we may lose a few species in the process.

      According to Wikipedia, magnetic reversals happen from 1 to 5 times per million years. That is not long enough time for a new species to evolve. Which in turn means that every currently existing bird species survived the last reversal. So why would they perish this time either ?

      Of course we might get lucky and the migrating flocks of bird-flu carrying birds who were about to wipe out the human species will all get lost and drown in the middle of the Atlantic. Once again, the day is saved, thanks to Geomagnetic Reversal !-)

      --

      Forget magic. Any technology distinguishable from divine power is insufficiently advanced.

  5. Yei! by suv4x4 · · Score: 5, Funny

    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!

  6. Imagine the customers.... by MindPrison · · Score: 4, Funny

    ...faces when they return to the shop to complain about their compasses showing the wrong direction.

    --
    What this world is coming to - is for you and me to decide.
  7. north = ? by novastar123 · · Score: 3, Insightful

    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?

    1. Re:north = ? by Anonymous Coward · · Score: 5, Informative

      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.

    2. Re:north = ? by 6ULDV8 · · Score: 5, Funny

      Offsite backup poles?

      --
      Pull my finger for my public key.
  8. Slightly off... by Justifiable_Delusion · · Score: 3, Interesting

    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.

    --
    Mad, adj : Affected with a high degree of intellectual independence. Ambrose Bierce - The Deveil's Dictionsary
    1. Re:Slightly off... by MadTinfoilHatter · · Score: 3, Insightful
      That's a good point. Geomagnetic reversal is actually a relatively poorly understood phenomenon http://en.wikipedia.org/wiki/Geomagnetic_reversal 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.

    2. Re:Slightly off... by 4D6963 · · Score: 4, Informative
      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.

      --
      You just got troll'd!
    3. Re:Slightly off... by ceoyoyo · · Score: 4, Interesting

      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.

  9. I think I saw this on the nature channel by Attrition_cp · · Score: 5, Funny

    I hear the penguins call it the War of Northern Aggression.

    --
    Touched By His Noodley Appendage.
  10. "No need to fret?" Like hell. by gblues · · Score: 4, Interesting
    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

  11. It's just... by Anonymous Coward · · Score: 5, Funny

    It's just the Earth's way of trying to degauss itself ... just not doing a very good job of it so far!

  12. Have you seen maps from 1590? by Anonymous Coward · · Score: 5, Funny

    According to those maps, the world was a different shape, and had huge monsters in the oceans.

  13. Cause for concern by cmeans · · Score: 5, Funny
    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.

    --
    Give a hand, not a hand-out.
  14. North will stay the same... by LinuxRulz · · Score: 5, Funny

    as long as the toilets in the northern hemisphere still flush clockwise.

  15. Need to Take Action Now by Nom+du+Keyboard · · Score: 3, Funny
    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.

    --
    "It's the height of ridiculousness to say for those 9 lines you get hundreds of millions."
  16. GPS to stay? Not necessarily. by emarkp · · Score: 3, Informative

    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.

  17. Re:Adverse effect on magnetic storage? by Valdrax · · Score: 3, Funny

    Clearly it will have a hideous effect on all hard drives, just like the way all your bits fall out when you accidentally rotate your laptop 90 degrees against the polar magnetic flux.

    --
    If it's for-profit but free, you're not the customer -- you're the product (e.g., the Slashdot Beta's "audience").
  18. Re:Adverse effect on magnetic storage? by Xtifr · · Score: 3, Interesting

    > is it at all possible that a switch in the earth's polarity would damage/erase any data

    No. The Earth's magnetic field is pervasive, but not very strong. And what there is has a negative/disruptive effect on magnetic media in any case. During the Earth's transition period, magnetically-stored data should be more safe, if anything. But probably not enough to measure.

    When I worked for a HD company, years ago, we did find that one of our magnetic-layer deposition machines had a very slightly higher failure rate than the others, and that one did happen to be at ninety degrees to the others, and someone once suggested that it might be being affected by geomagnetism, but most of the engineers thought that was nonsense, and it was never investigated further, as far as I know. Frankly, I think it was just a slightly more flaky machine--it was the first one the company had built, IIRC.

  19. Less strange than fiction by haelduksf · · Score: 3, Interesting

    There's an excellent novel by N. Lee Wood called Faraday's Orphans set in the apocalyptic aftermath of just such a reversal. Probably inaccurate, but interesting.

  20. Solution: Solar wind is going to create a new MF! by mha · · Score: 3, Interesting

    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.

  21. Re:Duh by Doc+Ruby · · Score: 3, Funny

    And you wouldn't survive the sabertooth tiger after I pushed you out of the cave, Anonymous troglodyte Coward.

    --

    --
    make install -not war