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Earth's Magnetic Field Weakens 10 Percent
caryw writes "Interesting story from the AP. 'The strength of the Earth's magnetic field has decreased 10 percent over the past 150 years, raising the remote possibility that it may collapse and later reverse, flipping the planet's poles for the first time in nearly a million years, scientists said Thursday. At that rate of decline, the field could vanish altogether in 1,500 to 2,000 years, said Jeremy Bloxham of Harvard University. Hundreds of years could pass before a flip-flopped field returned to where it was 780,000 years ago. But scientists at a meeting of the American Geophysical Union cautioned that scenario is an unlikely one. "The chances are it will not," Bloxham said. "Reversals are a rare event."'"
Now, when Magneto is weakest, it is the time for the X-Men to strike and remove the threat of the Brotherhood of Evil Mutants forever!
Don't blame Durga. I voted for Centauri.
Or was it Discovery channel?
Apparently this is supposed to happen every 600,000 years. During the flip everyone on Earth will be exposed to elevated levels of cosmic/solar radiation increasing the chances for cancer. The good news is we'll have multiple auroras all over the planet as the fields move around.
but we're overdue
A blog I run for the wealth
My TiVo captured it but I'm not going to let my kids watch it because it's pretty alarmist IMO (and, frankly, there's nothing we can do about it anyway).
Or maybe we can?
Yeah, I didn't feel like reading TFA. What will it do, aside from probably elevated exposure to radiation?
Those who can, do. Those who can't, consult.
As usual, I will probably be marked as flamebait, but sometimes people read rather than mod, so I'll post anyway. Creationists have done discussions on the earth's magnetic field before, which is one method that shows a young date for the earth: http://www.creationresearch.org/crsq/articles/39/3 9_1/GeoMag.htm
...the poles reverse...oh wait...
"The weakening -- if coupled with a subsequently large influx of radiation in the form of protons streaming from the sun -- can also affect the chemistry of the atmosphere, said Charles Jackman of NASA (news - web sites)'s Goddard Space Flight Center.
That can lead to significant but temporary losses of atmospheric ozone, he said.
Ozone Holes??
The north-south polarity may have weakened 10%. The totality of the field remains the same. The north-south polarity appears to be randomizing as it realigns into a south-north flip.
"The chances are it will not," Bloxham said. "Reversals are a rare event."'"
but overdue. these aren't governed by random chance like gambling; there _is_ a cycle
We've secretly replaced Slashdot with new Folgers Crystals - let's see if it notices.
This is just a hair-brained idea a-la "I Love Lucy" but would it be possible to generate a fake magnetosphere in the event that we are without one for a few hundred years?
IANAP but would it be possible to place a giant electromagnet at L1 and have it deflect incoming Solar wind and particles?
It would probably have to be very powerful and possibly large (nuclear powered, 100 KM long) but would that work?
Blaze a trail to the New World
Second, much of our electronic communications would be interrupted without this protection. For more information see this FAQ
Magnetic Poles May Be About To Flip.
;-)
So, all the discussions about end-of-the-world, and creating our own magnetic field are already available there.
J.
It was called "Magnetic Storms." A little sensationalistic, but it does appear that we are a few millennia overdue for a flip. A flip is preceded by just this kind of drop in magnetic force, as "islands" of positive polarity start appearing in the negative area and visa-versa. Already a big one near Antarctica.
Take a look at the website. It has a great video of a simulated flip. Scary stuff.
I, too, agree with those who have cited the period nature of these types of events.
The scientific tracking of this phenomenon - within the bounds of a burgeoning field called paleomegnetism - has shown that such events have been seen already.
If I remember correctly, the seafloor around the Mid-Altantic Ridge shows local magnetic field lines (embedded in rock) that exhibit directional reversal on a regular basis. The regular, gradual creation of new seafloor on both sides of this band of spreading magma locks in the direction of Earth's general magnetic field at the time of formation - showing, some think, that these occurrences are regular and repeatable.
And yes, we're definitely overdue. But, we're also overdue for a planet-killing asteroid impact, so I guess there's nothing to worry about. What's a little field instability among friends?
It should be noted, however, that there is some notion that periods during which magnetic shielding is lost probably does wonders for increasing evolutionary branching. Think of all the natural selection that gets done under such extreme environmental pressure...
Sorry for the ramble. IANAP, by the way, but IAAPT (teacher).
...is about to go on eBay.
My father is a blogger.
are we?
echo...
see, this is a great example of how 'left'/'right', 'up'/'down', 'positive'/'negative', 'clockwise'/'counterclockwise', and other conventions can be clung to and allowed to distort the truth.
for example, you care really badly which way compasses point, or more generally you care a lot about the polarity of magnetic fields staying how they are.
oh, really? well, do you care much at all about which way around the toilet your water swirls as it goes down the drain? of course you don't -- and it's a good thing because if you cross the equator and flush your toilet again, the water will go down the other direction.
the earth goes through a series of wobbles which lend its hemispheres 'seasons', while undergoing a process known as 'precession'. at the same time, the solar plane undergoes a bit of unsteadiness where it's located on the galaxy's arm, dipping over and under the galactic plane.
our solar system is heading toward the galactic plane, the denser part of the galaxy.
my intuition tells me that as we approach, we will notice changes in certain things that go 'one way around', either slowing or diminishing, and when we pass over -- ping? pong! -- even the magnetic field will be inverted.
but rest easy -- in this theory, you'll also be able to go to australia and experience the retro feeling of water going down the drain the way it used to in the united states.
also, magnetic pole flips aren't 'rare', they may have happened millions of times in the past at regular intervals, according to some geologists who have studied sedimentary rock layers and found that magnetically influenced particles in the sediment (settled over time,) pull this way, then that way, then this way again as they survey deeper.
"Stratigraphically the origin of agriculture and thermonuclear destruction will appear essentially simultaneous" -- Lee
As I recall from the Nova program, a field reversal was essentially caught in the act by a single layer of lava. The interior of the lava flow had frozen in it a magnetic field 6 degrees different from the field frozen in the top and bottom of the flow, which cool faster due to contact with the atmosphere and the ground. This happened in a short period of time (days or weeks?). So saying "at that rate of decline" is pointless, as the rate of change would probably increase during a reversal. To illustrate, I'd like to point out that the north magnetic pole has been migrating further north at an accelerating pace. Although the link's text claims the acceleration occurred around 1970, their map shows it started sometime between 1904 and 1948, with perhaps a brief deceleration in the '60s.
And the sun is becoming more active at the same time. Things could get quite interesting on our little planet.
"I'm so moist I'm sticking to the leather." -Kermit the Frog on The Late Late Show
The real reason for global warming!
oh my god, oh my god oh my GOD!
not the fall of rome, AGAIN??!!
it wasn't blasphemy! i said 'o me ga'. 'o-me-ga! omega-- fine, burn me at the stake.'
"Stratigraphically the origin of agriculture and thermonuclear destruction will appear essentially simultaneous" -- Lee
I think I saw a documentary on this. It's related to the centre of our planet stopping spinning or something like that, and they need to send some nukes down there to restart it.
I think the documentary was called 'The Middle', 'The Core', 'The Deep'... something like that.
You can accomplish anything you set your mind to. The impossible just takes a little longer.
So should I freak out or not -- it really doesn't say so (does it?)...
...we are from the government - we are here to help...
First, there is overwhelming evidence that the dipole component of the magnetic field has diminshed, reversed and strengthened only to diminish and reverse again many times.
Second, the measured dipole field strength is only one component of the total field strength. Extrapolating the age of the earth based on the dipole field strength alone is not based on any accepted science.
"Scientific" Creationists like to believe that they're using science to support their theist assertions, but that is just the problem. Science does not presuppose any conclusion and is effectively neutral any subject until logic, reason and experimentation point the way.
If Americans had elected in Al Gore in '00, we'd have the Kyoto Protocol in place and mans affect on the magnetic field would have returned to 1988 levels!
The Republicans are robbing us of our magnetic field!!!!!!!
At last, Australia will be on top of the world again!!
a world in progress...
I mean really, no matter how bad the radiation gets outside, it's not like we're gonna be feeling it. Hey, maybe with all the skin cancer, being pasty white will even be considered a sign of good health, and geeks will reign supreme.
Nah, wishfull thinking...
...we just let everone else THINK they are in control...
<DrEvil>MUHAHA... MUHAHAHA... MUHAHAHHAHAHAH!!!</DrEvil>
- sigs are stupid
Fact: Earth's magnetic field is dying
It is common knowledge that Earth's magnetic field is dying. Everyone knows that ever hapless Earth's magnetic field is mired in an irrecoverable and mortifying tangle of fatal trouble. It is perhaps anybody's guess as to which Earth's magnetic field is the worst off of an admittedly suffering Earth's magnetic field community. The numbers continue to decline for Windows but Earth's magnetic field may be hurting the most. Look at the numbers. The erosion of user base for Earth's magnetic field continues in a head spinning downward spiral.
All major marketing surveys show that Earth's magnetic field has steadily declined in market share. Earth's magnetic field is very sick and its long term survival prospects are very dim. If Earth's magnetic field is to survive at all it will be among hobbyist dilettante dabblers. In truth, for all practical purposes Earth's magnetic field is already dead. It is a dead man walking.
Fact: Earth's magnetic field is dying
"the field could vanish altogether in 1,500 to 2,000 years"
I'll cross that bridge when we get to it.
I just excreted .25 kg (just a wild guess; rounding to a fourth) into the toilet in the last 5 minutes, i.e., my body mass has decreased .15% over the past 5 minutes. At that rate of loss, my body could vanish altogether in 25 hours!
(I may not have done the math right (it's almost 4am), but you get the point.)
What about the current acceleration of the geomagnetic north pole towards the geographic north pole?
Could this be why big animals roam the earth in cycles? Less gravity... bigger animals? First big insects (dragonflies with two feet wingspans), big saurians, big mammals... what's next? Shaq?
A fool throws a stone into a well and a thousand sages can not remove it.
for global warming? more radiation = more heat in the atmosphere.
could it also be the reason for Ozone Holes and higher cancer rates?
I am the Alpha and the Omega-3
We're talkin' magnetic fields here, not gravity. Terran critters ain't got that much iron in their blood.
I'm presuming that gravity only fails if we don't meet the Kyoto Protocol targets by 2010.
Yes, I am joking. Sad that you need to think about both that and this, isn't it?
Here's an article on Earth's magnetic field which appears to say different stuff to the link referenced above. "Dr. Humphreys is an ICR Adjunct Professor of Physics and a physicist at Sandia National Laboratories, Albuquergue, New Mexico. The Laboratories have not supported this work."
Here's a (linked) article celebrating his straight-over-home-plate predictions about other planetary magnetic fields from when Voyager II validated his predictions. The Sandia footnote has this interesting appendix: "and they neither affirm nor deny its scientific validity.".
It's not linked above, but here's the CRSQ article which led to all of the fuss. The next Mercury flyby that measures magnetic fields should be interesting.
I'm fairly sure none of this includes direct mention of the Earth's core fields, so either the article I have in mind wasn't written by Humphries or I've missed it somewhere along the line.
Got time? Spend some of it coding or testing
Finally, a use for my tinfoil hat.
Of course, it says 1,500 to 2,000 years. By that time, Los Angeles will cover North America completely, so we won't have to navigate with devices. We can just follow the increasing street numbers... the former magnetic North Pole in Canada will be on 16,000,000 street and 2,000,000 avenue, or whatever.
I don't know where he went to college, but when I got my first STD I wised up fast. "Ohmigod! I'm mortal!"
Earth will be a complte mess if our poles shifted. Say goodbye to any type of satellite communication or gps system. Even your old fashioned compass would be 180 degrees off :)
I couldn't think of a sig.
Mate of mine must be immortal, then. (-:
He visited his doc because he felt a bit under the weather, and was told "Well, you had gonnorhea..." - his body had already flushed the disease, and the symptoms were it recovering from the effort.
Got time? Spend some of it coding or testing
Mercury should prove (or else support) his reasoning. We may get some answers there as early as October 2007.
Got time? Spend some of it coding or testing
The following quote is from here. But there are any other good resources out there.
"There have in fact been two periods in which mass extinction of a number of species, composed of a great number of individuals, occurred. One of these, at the close of Permian period, was characterized by the disappearance of nearly half of the species of animals then in existence, ranging from protozoans to land-dwelling tetrapods. At the end of the Cretaceous period a similar event occurred, in which a great variety of species again disappeared, including the dinosaurs and the flying and marine reptiles. In both instances the events coincided with the reestablishment of frequent magnetic field reversals following a long quiescent interval. The field reversal therefore seems to represent an evolutionary selective process of great importance."
Also note that we are believed to be in a "quiescent interval" at the moment, although all indications seem to be that it is soon to end.
I feel the analogy of the blind people each holding onto their part of the elephant is appropriate at this juncture.
Q.
Insert Signature Here
http://www.thecoremovie.com
-------- In Soviet Russia, "Soviet Russia" sigs hate Slashdot.
Perhaps I'm not making myself clear. Humphreys decides for no real reason to assume:
1. The universe is ~6000 years old.
2. The planets and sun were initially created out of water.
3. Some portion* of those water molecules had their dipoles aligned causing the initial magnetic field.
4. At some point, God transmuted the water into whatever complex mix of elements/compounds that sun or planet now has.
5. God left the inital magnetic field due to those water molecules intact after transmuting them.
6. The field decays exponentially** as those water molecules come out of alignment (even though those same water molecules are no longer there).
*Humphreys gets to decide exactly what fraction of water molecules were aligned in the beginning, without any possible idea of what it was other than that value when plugged into his equations produces the known current magnetic field of that body. He assumes/back calculates values of 25% for all the planets save Jupiter, which to quote Humphreys "So it looks as if God pulled out nearly all the organ stops when He orchestrated Jupiter. Not only did He create a larger mass of water, but He lined up more than 90 percent of the water's hydrogen nuclei." No reasoning for this is given!
**Now one of the many problems with Humphreys' idea is that there is only one check on his exponential decay times: the Earth. There have been measurements of the Earth's magnetic moments for about 150 years, using different methods with different sources of noise and systematic error. Humphreys makes yet another assumption that these data are taken at face value and for no real reason other than his need for an exponential fit applies an exponential fit, despite the fact that two straight lines probably fit the data much better as there is drop off from 1835-1935, but is essentially constant afterwards. It gets worse. An important parameter in Humpreys' calculations for determining the current magnetic moment is the decay time T, or the time it takes for the field to (exponentially) decrease to 36.8 percent of any given value...but "D2cay[sic] times are deduced front created and present moments." So in addition to the above assumptions (including exponential decay) we have circular reasoning! Besides, Humphreys has nothing to say about his wide range of "decay times," which range from less than 360 years to greater than 41,000 years. He also doesn't show how his magnetic moment at the moment of creation (Mc) is related to the current magnetic field.
Humphreys took the known value of the Earth and Saturn, and guessed that Neptune and Uranus would be somewhere in the middle...which gives a couple orders of magnitude to be "right" in. Nothing got burned across any plate, the best you can give him is he got a cow pie to stick to the broadside of a barn. If you want to believe in miracles that's your business, but you can't call your belief in Humphreys' theory of magnetic fields by divine intervention science.
about 7 years ago I was told to look out for the polar switch. The psuedo tribal folks that were predicting it figured it meant that Antartica (the land mass) would switch places with the North Pole. They were predicting that the insides of the earth were going to flip flop, so that it would in effect be upside down. They called this the 'earth changes', and that the earth's crust would be completely ravaged by earthquakes and lava flows, mountains would fall and new ones would rise, cities would be buried, only a handfull of living beings would survive. Sounds like classic armageddon, right? They said it had happened before, and that we are due for another one. I did not feel up to explaining what would and wouldn't be likely to happen in a polar shift, they always found a way of refuting science completely.
TallGreen CMS hosting
It's interesting to see that the majority opinion on the temporary loss of a net magnetic field (i.e., no magentosphere) would be nothing more than an inconvenience for satellite communication and herald the introduction of SPF 80.
IAAP. If we assume the Earth had no magnetosphere, and the soloar wind was not being routed to the poles, then the Earth would essentially be a very massive comet.
Solar wind has a lot of linear momentum (the proton density is small, but protons have lots of mass). Momentum is always conserved, but because of the field, the momentum is being transfered to the Earth through the coupling of the solar wind and the magnetic field (and since the solar wind impacts the atmosphere only at the poles, there is no net change). Now the Earth is pretty darn heavy, so the solar wind is like nothing at all.
Now consider the scenario if there is no field (or a bunch of randomly aligned fields). The solar wind hits the atmosphere everywhere on the day side. Wow! Aurora Universalis!! How pretty! That's true for a while. More importantly, momentum transfer is now occuring through interactions with the atmosphere. Ever see the tail of comet? That's the same thing, exepct in that case the solar wind is interacting with really cold water (solid ice). The atmospheric blanket that surrounds our planet is incrediblly light, and would essentially be blown off in a very short amount of time. (Comets survive since the tend to spend the majority of their existance out beyond pluto where the proton density is REALLY low, they only brighten up when the come visiting our neck of the solar system, which is many cases, is farther from the sun then we are). We could be talking a matter of decades, or even years until the Earth lacked an atmosphere.
This leads to the obvious question. If the Earth does lose its atmosphere every 1-2 million years. How does complex land dwelling life evolve?
This is the problem of knoing too much physics and staying up until 6 am.