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Dispelling Myths About Geomagnetic Reversal

UniverseToday has an interesting look at geomagnetic reversal, the process in which the Earth's magnetic poles trade places. The article cites known trends and recent studies to debunk doomsday myths and unsubstantiated claims about the process. One such study is attempting to model the earth's core with a 26-ton ball of molten metal. Another recently found evidence that the Earth has a second, weaker magnetic field. "We do know that this magnetic pole flip-flop has occurred many times in the last few million years; the last occurred 780,000 years ago according to ferromagnetic sediment. A few scaremongering articles have said geomagnetic reversal occurs with 'clockwork regularity' — this is simply not true."

22 of 158 comments (clear)

  1. it switched last week... by AliasMarlowe · · Score: 4, Funny

    ...and the bankers flipped.

    --
    Those who can make you believe absurdities can make you commit atrocities. - Voltaire
  2. Lets see it... by alexborges · · Score: 3, Funny

    I wanna see it flip and take it all with it.

    Lets return to the earth, have half of us killed, and go back to hunting venison like we very well used to before some assholes started to chat about this "civilization" crap we are in right now.

    Fuck that.

    Back to the trees people, this stupid "modern society" thing didnt work.

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    NO SIG
    1. Re:Lets see it... by Daimanta · · Score: 4, Funny

      Says the guy posting to Slashdot.

      --
      Knowledge is power. Knowledge shared is power lost.
    2. Re:Lets see it... by meringuoid · · Score: 3, Informative
      Lets return to the earth, have half of us killed, and go back to hunting venison like we very well used to before some assholes started to chat about this "civilization" crap we are in right now.

      If we tried to live as hunter-gatherers, we'd need to kill off a whole lot more than half of us. World population is now something like 6.6 billion. We didn't reach 3 billion until 1961. In 4000 BC, about the time civilisation was really getting going in Egypt and Mesopotamia, the population of the world was more like 20 million. That's the kind of figure you're looking at for a world of hunter-gatherers. About the same as the population of New York city.

      --
      Real Daleks don't climb stairs - they level the building.
    3. Re:Lets see it... by Belial6 · · Score: 4, Funny

      Well, if we went through a phase of hunting people instead of venison for food, the plan just might work. Then not only do you get a reduced population due to food harvesting, but you also get a reduced population due to wide spread disease. Whoo Hoo! All our problems are solved!

  3. Get ready for it! by OrangeTide · · Score: 5, Funny

    "we'll be exposed to the vast quantities of radiation blasting from the Sun; with a reversing magnetic field comes a weakening in the Earth's ability to deflect cosmic rays."

    Finally, a use for our tinfoil hats!

    --
    “Common sense is not so common.” — Voltaire
  4. Unknown by Mortiss · · Score: 3, Informative

    AFAIK the process takes a very long time and would be very gradual and although it may begin soon it would take a long time and allow for everything to adjust, if required.
    However, one can never be really sure... any data on effects of previous switches?

  5. Re:Not really worried. by Anonymous Coward · · Score: 5, Insightful

    Doesn't rotating the device 180 degrees have the same effect? If it takes you 0.5 sec to turn a North-facing iPod into a South-facing iPod and it doesn't break it, just how fast a geomagnetic reversal do you have in mind?

  6. Comment removed by account_deleted · · Score: 4, Informative

    Comment removed based on user account deletion

  7. Love the look in his eyes by David+Gerard · · Score: 3, Funny

    The guy who runs the 26 ton ball of molten metal. That's a Mad Scientist gleam in the eyes if ever I saw one.

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    http://rocknerd.co.uk
  8. Best quote ever by e2d2 · · Score: 4, Insightful

    Without GPS, our airliners will also plough into the ground

    Goddamit man, we can't land without GPS!

    Good thing Lindberg had GPS, otherwise he would've gotten lost like Earhart did when her GPS failed.

    GPS approaches are actually relatively new and are just now in the past few years showing up on modern Jeppsen charts.

    That being said, modern GPS based navigation is so sweet. Nothing is sweeter than jumping into a plane with a G1000 GPS based system, complete with XM weather and traffic warning systems and seeing it all on configurable glass panels. But if it fails there is always backup "classic" gauges one can use. And even if that fails there is ye olde grey matter.

     

    1. Re:Best quote ever by Anonymous Coward · · Score: 5, Informative

      I build the navigation systems used in many commercial aircraft. Primary system is inertial, not GPS; input from multiple accelerometers is integrated to determine velocity and position.

    2. Re:Best quote ever by e2d2 · · Score: 3, Informative

      I'm a software developer and I once picked up a few college textbooks on aerospace navigation, specifically ones related to control system design (state methods, optimal filtering/control, etc). and I have to say one thing - you sir are a God amongst mere mortals. To say it's tough is an understatement.

  9. Listen by jayhawk88 · · Score: 4, Funny

    Just because I don't have a fancy "doctorate" or even "college education", doesn't mean you can just dismiss my theories! Einstein didn't go to college after all, look where he ended up!

    I'm telling you, my theory is solid. I saw this show on the History Channel the other day that was talking about what kind of propulsion UFO's might use, and it came to me: What would happen if the Earth's magnetic field happened every 780,000 years and 300 days, exactly? That would mean it would happen again in November! Our only hope is to align every source of magnetic material in the world along north-south magnetic lines! I've already done this with my stove, fridge, and just to be safe my wireless network. I encourage all of you to do the same!

    I am not crazy people! My scientific theories are backed up by some of the finest dramatization programs the Discovery Channel has to offer!

  10. Re:Not really worried. by jcorno · · Score: 4, Informative

    The only reason I'd really be worried about the magnetic field flipping is that a changing magnetic field induces a current in a conductor. This means every electronic and electrical device with a closed loop would experience a large current, likely destroying the smaller equipment.

    The earth's magnetic field is about half a gauss at the surface. It's weaker than the field generated by a refrigerator magnet. I think it's safe to say that the flip is not gonna destroy your electronics.

  11. Re:Not really worried. by Anonymous Coward · · Score: 3, Informative

    A more comprehensive chart at a variety of scales (zoomed in on the last ~1Ma (million years) the last 5Ma and over the last 160Ma is available on the relevant wikipedia page about geomagnetic reversals. The fluctuations are anything but "regular". Anyone who describes them that way doesn't know what they are talking about. Sure, like anything, you can calculate a mean duration, but the variance is very high, with durations from 10s of millions of years to 50000 years. "Clocklike regularity"? Sure, if your clock ticks 1 second one time, and 5 minutes the next.

    If these were bad events, there would be obvious correlation to major extinction events. There simply isn't, and people have looked really hard (because it would be interesting if there was).

  12. Re:It's all hopelessly out of date! by Anonymous Coward · · Score: 5, Informative

    That's utter nonsense. The magnetic field is continuously monitored from orbit by all sorts of satellites. One of many such satellites is Ørsted. There are papers all through the 1990s and 2000s that analyze the data from this and the others. People don't fund surface expeditions to study large-scale magnetic field variations because they've been largely superceded by satellite measurements. The only people interested in surface measurements are usually exploration geologists (e.g., looking for signs of sub-surface mineral deposits).

  13. Re:Ah, pay attention to the article ... by fyoder · · Score: 3, Informative

    If you've ever seen a small chunk of pure sodium tossed into a sink full of water in a high school chemistry class ... and then think how much this guy has ...

    Here's a blog post with a couple of vids of sodium water reactions. The US military's post WWII disposal of sodium in a lake is particularly impressive.

    --
    Loose lips lose spit.
  14. Don't worry by mangu · · Score: 4, Informative

    why is this a cataclysm?

    It really isn't. The problem itself is not the reversal itself, but the period inbetween, when the magnetic field will be very small or inexistent. The earth's magnetic field has the effect of diverting charged energetic particles emitted by the sun towards the poles. It's those particles entering the atmosphere that cause the northern lights. Without a magnetic field, they would penetrate more into the atmosphere, possibly causing harm to living beings.

    However, this reversal will happen several hundred years from now. By that time, I'm sure that, if I'm alive, it will be because we will have some pretty advanced medicine, capable of handling the increased radiation effects.

    1. Re:Don't worry by mangu · · Score: 5, Informative

      I still think cellphone antennas can affect more in this cancer matter than something that has happened before in Earth with no big impact at all

      Cell phones transmit at a relatively low frequency, which is called "non-ionizing".

      Electromagnetic radiation is transmitted by particles called photons, each of which carry a fixed amount of energy, proportional to its frequency. Therefore, to transmit a given amount of power, it takes more low-frequency photons than high-frequency ones. There is a certain frequency, higher than what cell phones use, where the energy of a single photon is enough to break the chemical bonds that keep molecules together, that's what is called "ionization".

      At lower, "non-ionizing" frequencies, you can send as much power as you want, you may cook the tissue, but the chemical bonds will not be broken in the same way, because the photons don't have the required energy.

      The sun emits particles in a very wide range of energies, including ionizing ones. The charged particles with ionizing energy which are diverted by the earth's magnetic field are certainly more dangerous than any cell phone antenna.

      The dangers of non-ionizing radiation have been the subject of debate, but one should be careful when judging the data. With high enough power, like in a microwave oven, there will be damage to living tissues, of course, but it's in an entirely different level from ionizing radiation, where a single photon is enough to break a molecule and, pick your worse nightmare, start a cancer or cause a mutation.

  15. 4 * 10-13 Hz by S-100 · · Score: 5, Informative

    I don't think a field change at .0000000000004 Hz is going to induce much current anywhere.

    TFA does little to debunk what may be the biggest danger, and that is the disruption of the Van Allen radiation belt, and the protection that it provides to the Earth from cosmic rays. While I'm sure that the radiation belt would re-establish itself to match the "flipped" magnetic poles, it may not do so during the transition period. And this pole flipping may be quick in geological terms, but it may take a number of years, and during that time, part or all of the Earth may be bombarded with cosmic rays. Or, the distorted field may actually concentrate cosmic rays upon parts of the Earth many times what you'd find in space outside the belt. These cosmic rays would cause massive increases in cancer and genetic mutations in all species of plants and animals, and even a stack of tinfoil hats won't help. Much.

    Increases in cancers would not be detected in the geological records, and periods of high radiation may explain things like the Cambrian Explosion, where many new species spontaneously appeared. If the field swaps by rotating from pole to pole, the radiation belt will probably just follow along, but if the poles swap by diminishing to zero and then building at the opposite pole, there will be a very dramatic change (and possible collapse) of the radiation belt that could very well affect life on the planet very dramatically (from our perspective). The scourge of AIDS killed 2.1 million people in 2007. That's .03% of the world population. Just a doubling of the current rate of death due to cancer would kill 7.9 million people - almost four times that of AIDS. And with sufficient radiation exposure, the cancer rate could well escalate way beyond 2X.

    Of course, ancient calendars not withstanding, there's no reason to believe any of this is likely to happen during our lifetimes.

  16. Debunking Doomsday Myths? by jvkjvk · · Score: 3, Interesting

    The article is actually a rant against the 2112 Millenialism of a particular strain of people that have imprinted the mayan great cycle myth at a precognitive level through the influence of McKenna (whether they know it or not). At best, the article says that it's not very probable that a reversal will happen in our lifetime and if it does, "satellites may malfunction and migrating birds may become confused" but that's about it. Without a shred of proof given to that. It could presumably be much worse, so we should probably at least look at it.

    though I do concur that the world probably won't end dec 21 2012.

    However it also makes reference to a type of potentially catastrophic type event, a 'polar shift', which is really rare. Of course, all that means is that it is eventually inevitable. So there's another ticking clock. Has anyone come up with a clock incorporating all the known doomsday events that are actually going to happen sooner or later? e.g. catastrophic asteroid, polar shift, super solar event, whatnot? Would be interesting.