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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.
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
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).
I didn't think it was too "alarmist" as towards the end they talk about the only major negative effects of a weakened magnetic field and eventual switch is a slight increase in cancer (compared with all the cancer in the world as we know it today.) It also presented the possibility of having more than 2 poles, and a positive effect of the was having the auroras being visible all over the Earth. I showed this in my Earth Science classes this weeek, as we just started talking about how magnetic reversals are recorded in igneous rock, and is one of the pieces of evidence for sea floor spreading and plate tectonic theory.
...is about to go on eBay.
My father is a blogger.
Time to panic!
Didn't you see the movie "The Core?" (It stars the lucious Hillary Swank and shows the devastation that awaits a loss of the magnetosphere. See http://www.imdb.com/title/tt0298814/)
People with pacemakers will all die! Pigeons will get confused and fly into buildings! Electrical Superstorms will destroy ancient Roman Colosseums!
READ the US Constitution, the Bill of Rights and the other amendments! http://lcweb2.loc.gov/const/const.html
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
I think there's a problem with those high energy protons destroying ozone (mentioned in TFA), so sunblock might be necessary. And even if the total field doesn't weaken, during the reversal the dipole moment of the field will, leaving quadrupoles or octopoles or something. A magnetic field parallel to the ground is a good shield against charged particles, but a perpendicular field (a pole) actually guides charged particles towards the ground, hence phenomena such as aurora. If a pole erupts in my neck of the woods, I'd seriously consider moving elsewhere. Or dust off the ol' tinfoil hat and put it on.
"I'm so moist I'm sticking to the leather." -Kermit the Frog on The Late Late Show
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.
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.
Um, no.
Serve Gonk.
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...
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