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Dispelling Myths About Geomagnetic Reversal
Posted by
Soulskill
on Sun Oct 05, 2008 12:43 PM
from the exploring-our-polar-system dept.
from the exploring-our-polar-system dept.
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."
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it switched last week... (Score:5, Funny)
Twice a Year! No? (Score:3, Funny)
I thought this happened twice a year and Congress mandated it. Spring forward and fall back and all that.
Lets see it... (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.
Re:Lets see it... (Score:5, Funny)
Says the guy posting to Slashdot.
Parent
Re: (Score:2, Funny)
I bow in signal of respect.
Re:Lets see it... (Score:4, Informative)
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.
Parent
Re:Lets see it... (Score:5, Funny)
Parent
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Except for the problems of the victims, whose problems escalate rapidly before becoming completely irrelevant - they don't get solved!
Re: (Score:3, Interesting)
There's evidence that cannibalism leads to prion diseases (like http://en.wikipedia.org/wiki/Kuru_(disease) [wikipedia.org] ). So have a nice meal!
Re: (Score:3, Funny)
And face it, losing would still be less painful than actually watching reality tv.
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Yeah, I heard something like that.
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Then why let it take away the control over your happiness?
I know c11n doesn't work. It can't bring you anything but what you would have otherwise; neither will it bring you happiness nor stop you from being happy. It's your own choice to be happy or not, and your own choice to let someone else choose for you.
Get ready for it! (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!
Unknown (Score:4, Informative)
However, one can never be really sure... any data on effects of previous switches?
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Considering we have to look for evidence of the previous switches in three-quarter-of-a-million year old sediment, any data we have on effects is going to be open to interpretation. It's not like we had reporters back then.
Re: (Score:3, Funny)
Can we not just ask someone in the RIAA? After all, their business model was developed around then.
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The burst of solar wind, cosmic rays and all that crap might have no greater effect on the living beings themselves, but how about all our delicate electronic stuff that we are used to depend on?
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Lost, due to a hard drive failure, 780,000 years ago.
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Well, considering humans in almost modern form have lived through at least one pole reversal, and land live has lived through hundreds or thousands, cataclysm is pretty unlikely.
Love the look in his eyes (Score:4, 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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Re:Ah, pay attention to the article ... (Score:4, 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. [backofthebook.ca] The US military's post WWII disposal of sodium in a lake is particularly impressive.
Parent
Best quote ever (Score:5, 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.
Re:Best quote ever (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.
Parent
Re:Best quote ever (Score:4, 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.
Parent
Listen (Score:5, 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!
Re: (Score:3, Funny)
We might have listened to you, but the people at UniverseToday have been staying at a Holiday Inn Express, so they're much better informed...
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It's all hopelessly out of date! (Score:2, Interesting)
The fact is that the last serious efforts to measure the Earth's magnetic field in the South Atlantic were terminated in the mid-1980's when the British government pulled the funding for their geomagnetic programme in the South Atlantic. Everything that's been speculated upon since then is postulated on their measurements of rapid ans significant weakening of the magnetic field in the South Atlantic... but nobody's been watching since the mid-80's.
So we don't really know.
Last time anybody bothered to look,
Re:It's all hopelessly out of date! (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 [wikipedia.org]. 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).
Parent
Nature won't be the cause. (Score:2)
I guarantee you, when we have this conversation again in heaven or hell, it was some retarded human in a position of power that killed us all.
Never underestimate the stupidity of humanity. A huge killer EMP would perhaps be a welcome relief.
Hidden objectives. (Score:2, Funny)
All we need is a lvl 86 mage (Score:2)
And let him cast Dispell. Should work against any "geomagnetic reversal" buff cast on the earth.
Debunking Doomsday Myths? (Score:4, 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.
Re: (Score:3, Informative)
Re:Not really worried. (Score:5, Informative)
Basically, to track it they can look at the expanding mid-Atlantic ridge, and see how the poles were when the lava cooled over time. Neat stuff.
Parent
Re: (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 [wikipedia.org]. 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
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Re:Not really worried. (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?
Parent
Re:Not really worried. (Score:5, Informative)
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.
Parent
Re: (Score:2)
If that's the case, why is this a cataclysm?
Don't worry (Score:5, Informative)
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.
Parent
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Re: (Score:3, Funny)
Re:Don't worry (Score:5, Informative)
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.
Parent
Re: (Score:2)
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.
Really? And the fact that the Earth's magnetic field keeps us protected from extremely harmful cosmic radiation doesn't even register with you?
I am not saying the switch would cause a disruption of this field, but I guess that could happen. And if did happen, depending on how long it would last, it could have catastrophic consequences. It may not wipe out life as we know it, but something major would happen, something less than pleasant.
4 * 10-13 Hz (Score:5, Informative)
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
Of course, ancient calendars not withstanding, there's no reason to believe any of this is likely to happen during our lifetimes.
Parent
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He isn't making claims. He's disputing claims that other have made.
By your reasoning we're "due" to spontaneously lose our left index fingers in the next generation because it's technically possible there's no evidence to suggest that we're not.
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each individual iron atom was said to have its own tiny field in one lecture I had... I would think it would certainly be possible to have a "Secondary field" but how do we tell if it's pernament, or just an effect of the iron atoms lining up in large groups, without the "straightening" influence of the main field.. I have no clue. And I'm not sure we know how that all works yet either(why a secondary field, but no tertiary field? is the secondary field a mechanism that happens in the mantle, but just the