The New York Times On Earth's Magnetic Flip-Flop

TolkiEinstein writes "The New York Times reports that, relatively speaking, compasses may soon point South. It's long been known that Earth flips magnetically every half-million years or so, and, with the north pole's magnetic field at about 10-15 percent [less than] its strength of 150 years ago, many geologists feel a flip is coming up. Computer simulations also suggest that the current state of the magnetic field is indicative of an upcoming flip. Though it would take hundreds of years to complete, the impact on life may be significant but not catastrophic, including phenomena such as power-outages, satellite malfunctions and disruptions in the rhythmic functions of some animals such as loggerhead turtles. The EU plans to launch a trio of satellites in 2009 to assume polar orbits & monitor the field." (Cross your fingers for some nice solar wind.) Update: 07/13 17:02 GMT by T : Note: the summary here originally misstated the Times' article; the field 's strength has decreased 10-15 percent, rather than to 10-15 percent.

Re:Worldwide Aurora

[JosKarith]

"since the magnetic field will be weakened"
You better pray not. The magnetic field is what keeps some of the nasty radiation in space out of our safe(ish) little bubble. If the magnetic field does weaken signifigantly, may I suggest investing in some Factor 3000 sunblock...

Time for the editor to RTFA

[johnmig]

It has to be pointed out that there is a significant difference between "The field's strength has waned 10 to 15 percent." which is what the article says; and "the north pole's magnetic field at about 10-15 percent it's strength of 150 years ago" which is what Timothy says. The former means that the field strength is still 85 to 90 percent of the original value (still nearly intact), while the latter means that it is only 10-15 percent of that value (nearly gone). This distiction not insignificant. That being said, it's still neat to follow (even though I don't think that I'll be around at the end).

Re:Mayan Calendar ends in 2012, coincidence ???

[Anonymous Coward]

The seasons are such because of the earth's tilt, rather than any magnetic effects.

If you have kde run kworldwatch in speeded up mode to watch the sunlight distribution.

Re:Mayan Calendar ends in 2012, coincidence ???

[Aardpig]

It will be hilarous if the poles flip about the time the Mayan calendar ends, hopefully it will go as gracefully as scientists have predicted.

Unlikely, since a full flip takes a few hundred years; it is not a sudden, catastrophic effect.

As The southern hemisphere has its winter during our summer, I am wondering if the seasons will flip flop as well ???

Unlikely, since the seasons are defined by the orientation of the Earth's rotation axis to its Solar orbital axis; they have nothing whatsoever to do with the magnetic axis.

I also wonder if the polar shift will effect magma flows ...

Unlikely; the fields are far to weak, and get even weaker during a field reversal.

I wonder if the magnetic field has any effect on plate tectonics too .

Unlikely, for the reasons I give above.

Re:What

[TheProcrastinatorTM]

Doh, stupid enter key....

What I meant to say before bumping the enter key on an incomplete post was...

In the summary, it says the field is at 10-15% of where it was 150 years ago, but the article says it has WANED 10-15%, which would actually make it 85-90% of where it was 150 years ago...

Typical - So typical

[Anonymous Coward]

As is the case with most /. posts, paying attention to detail gets thrown out the window.

From the poster's text:

"and, with the north pole's magnetic field at about 10-15 percent it's strength of 150 years ago"

From the article itself:

"The field's strength has waned 10 to 15 percent, and the deterioration has accelerated of late"

Those two quotes are not the same. The poster's lack of attention to detail has turned the articles 10 to 15 percent reduction (a relative value) into a 10 to 15 percent strength (an absolute value). The meaning is totally different, and the poster should apologize for spreading mis-information.

Interesting Show

[fdiskne1]

I had heard about this theory, but never believed it. Then I saw a Nova [pbs.org] show on PBS [pbs.org] called Magnetic Storm [pbs.org]. It's very well made and very interesting. By the end of the show, I believed the poles are set to reverse and it's just a fact of nature. Nothing we can do about it except research and prepare our way of life so things don't go to Hell in a handbasket.

Magnetic chaos

[Nosher]

Then real fun with the flipping of the magnetic field is not that it moves uniformly from one pole to another over time, but that as it breaks down, tens or hundreds of "north" and "south" poles can develop which are spread all over the planet - see this article in New Scientist [newscientist.com]. With any luck, maybe my house might end up at one of these new "North Poles" for a while, so at least I can say I've been there :-)

Re:Hope we don't get irradiated...

[Anonymous Coward]

I'm a geologist and can tell you there has never been an extinction event associated with or correlated to a magnetic reversal. These are common events that have taken place quite a few times since life arose on this planet.

For whatever reason everything will turn out ok. That being said, they didn't have computers and power grids back then.

Why read the Times for Science?

[arrogance]

How about Scientific American [sciam.com] for how long the reversals take?

the average duration of a reversal is close to 7,000 years. The analysis further suggests that the timescale of the transition differs at various latitudes. During the last polarity shift, approximately 790,000 years ago, sites close to the equator underwent the 180-degree change over the course of 2,000 years, but the process took closer to 10,000 years in midlatitude regions.

There's also a good article on WHY the reversals take place [sciam.com] by Gary A. Glatzmaier, the guru of terran magnetic reversals. You gotta specialize in something I guess.

Less a flip and more a migration...

[TheQuestion]

I'm not a geologist, but don't things on this scale happen very slowly? You wouldn't go to sleep one night with your compass pointing north and suddenly have it point south when you woke up. This would happen gradually over hundreds or thousands of years. Although this is geologically overnight, the magnetic pole wouldn't move significantly during a person's, or turtle's, lifetime.

Having said that, I doubt even the turtles that rely on the field for navigation would notice. They would adapt to sense the less powerful field over time or they would loose the need to use it. Navigation is done by point of reference. And since the navigational lines of force are moving so slowly, the turtles wouldn't care. The North Pole being 200 miles from where it was for the turtle's great grandparents really doesn't matter to today's turtle. He just wants to get back to where he started from a year or so ago. The shift should be slow enough for him to do this.

The reduced magnetic field seems to be much more of a concern. But, again, we will adapt much like the turtles will. But instead of adapting our biology, we'll adapt our technology. It's not that we can't make a satellite or power grid that can handle solar wind and storms; it's just that we haven't done it. Why not? We haven't needed to. Think of the reduced magnetic field as job security.

Re:Hollywood Blockbuster?

[julesh]

They did ...

That should have been linked to the "insultingly stupid movie physics" review [intuitor.com].

Magnetic Reversals

[JollyGreenLlama]

The Geological Survey of Canada has a well written and informative article [nrcan.gc.ca] on this subject. Some basic findings from the article include:

"Although fast by geological standards, reversals are by no means quick on the human time scale. They take roughly 5,000 years, with estimates ranging from 1,000 years and 8,000 years.

Both the total magnetic field and its dipole component decrease substantially during a reversal to values that range from 10% to 25% of the pre-reversal strength.

A reversal does not proceed in a uniform fashion. Large and rapid changes in direction and intensity are punctuated by periods of little change. During some transitions the field starts to change but then rebounds to near normal before the reversal finally goes to completion.

The scarcity and ambiguity of observations have led to two competing theories explaining how the magnetic field pattern changes, and how the magnetic poles behave during a reversal. According to one theory, the magnetic field remains predominantly dipolar during a reversal, and the poles migrate along preferred paths from one hemisphere to the other. According to another theory, the dipole portion of the magnetic field shrinks to zero but then regrows with opposite polarity. During the interval during which there is no dipole, the non-dipole part of the field persists, and the magnetic poles would not migrate in a systematic fashion."

While the article does little to posit the consequences of these competing theories, it does provide a good deal of insight as to why and when the changes occur. It does conclude, however, that "many investigators believe that the trend [magnetic pole weakening] will not continue and the field will regain its strength, as it has many times in the past."

Re:Turtles

[Like2Byte]

OK, it was bugging the crap out of me so here are what CPIP and LTIP mean.

CPIP: Carrier Pigeon Internet Protocol
LTIP: Loggerhead Turtle Internet Protocol (I'm guessing)

{ala Snapple}(There are many other definitions for the acronym LTIP. Choose one that fits you.)

Re:Mayan Calendar ends in 2012, coincidence ???

[Anonymous Coward]

This must be modded funny because of how ridiculously wrong it is. I hope it was intended to be wrong...

In any case, besides the seasons having nothing to do with the magnetic field, you are also wrong about the electromagnetic force. It's very strong. Many many many times stronger than gravity.

Re:Worldwide Aurora

[JosKarith]

Nope - just the DNA in the outer few millimeters of your body.
The penetration isn't good because they expend all their energy quickly.
Think of it like birdshot from a shotgun - the penetration isn't exactly great but you'd rather be hit on an armoured bit any day
Hell, who needs skin anyway? It's so...millenial.

Re:Turtles

[Math Avenger]

Actually, it's not that random; Loggerhead turtles -- indeed, all sea turtles -- use the Earth's magentic field as an aid to navigation [wikipedia.org]. Most animals know for their ability to return to certain locations use the variations of the magnetic field as a means to orient themselves geographically. So, a disruption or flip-flop of the magnetic field would send these species into a loggerhead with their own insticts.

Re:Magnetic Reversals

[way2trivial]

Even the weakening currently under way may be a false alarm. The field often gets very weak, then bounces back, never having flipped. As Ron Merrill, a magnetic-field specialist at the University of Washington remarked when asked whether we're in for a reversal: "Ask me in 10,000 years, I'll give you a better answer." So hang on to your compass. For the foreseeable future, it should work as advertised.--Peter Tyson [pbs.org]

Re:Worldwide Aurora

[Rogerborg]

Van Allen belts [wikipedia.org]. Radiation != UV. You're a troll or a junior schooler.

Re:Loss of atmosphere

[TheMeddler]

The ice ages are closely correlated to changes in the earth's orbit, usually referred to as Milankovich Cycles in reference to the first proponent. These consist of a 21,000-year perihelion cycle, 41,000-year obliquity cycle, and a 100,000-year eccentricity cycle. Since they all overlap, the superimposed curve is a bit uneven, just like the climatic cycle. Slide [slashdot.org] The 100k cycle is thought to have the greatest impact on climate.

Here's a brief overview of these cycles [slashdot.org]

There are, of course, a host of other factors that influence climate - for example, episodes of warming related to methane releases.

Thermal [slashdot.org]

Re:Worldwide Aurora

[jav1231]

Nova did a story on this that was quite fascinating. They covered the bases very well too and you're right. The Earth would be battered with more solar particles because the magnetic field currently protects us from it. We will likely see more instances of skin cancer too. On the "bright" side, you will likely see more Northern Lights in odd places like maybe Florida and Central America. (Okay, YOU won't, but your great-grandkids might.) Unfortunately, someone on the extreme left will miss the point completely and see this as a chance to gain power and headlines by blaming rich, white Americans (see "Global Warming").

This happens frequently... not a reversal

[goatbar]

Okay yall... being a paleomagnetist and dealing with this topic all the time, I have to say that it is NOT LIKELY that this is the beginning of a reversal. The field goes up and down at all kinds of frequencies. If you look at a graph of the Sint 800 [nature.com] (sorry it's a tiny figure) you will see all sorts of ups and downs for the last 800000 years during the bruhnes normal period. The last big low is called the Laschamp and was about 35-40 thousand years ago. Today's field is so far above that.

The magnetic field is a 'random process'. There is no real good statistical predictor of when the next reversal will happen.

Re:CRTs will be obsolete

[rabtech]

Note to moderators: This isn't true - this should be moderated "funny", not "interesting".

Sure its true.

[rebelcool]

Simple googling... shows it is [repairfaq.org]

Mainly it occurs on high end monitors. And they have sophisticated means built in to combat it.

Re:This would be good but

[feargal]

Going OT, but you should check out the Gall-Peters projection [wikipedia.org] which represents countries based on their land area, which produces strikingly different results [wikipedia.org] than that of a conventional [wikipedia.org] map.

Of course, all 2D maps will be wrong in some aspects, and the Gall-Peters approach distorts the actual shape of the land-masses. You could do worse though for a wallchart sitting in a classroom though.

Re:Worldwide Aurora

[cjameshuff]

This seems to be a common misconception. The solar wind is not a blowtorch that blasts any unprotected atmosphere into space. It will very slightly increase the rate of atmosphere escape, but it will still happen so slowly that it will probably not make a difference until after the sun ages enough to render Earth uninhabitable anyway. We have one big counterexample to that theory...Venus has slightly less gravity than Earth, and virtually no internally generated magnetic field, only a barely detectable one induced by the sun. It also receives over 1.9 times as much solar radiation as Earth, and over 4.4 times as much as Mars, yet its atmospheric pressure is 90 times as high as that of Earth...that's about 12000 times as much as Mars. Mars has little atmosphere because of its formation...it likely lost some gases that would have formed its atmosphere to Jupiter, and got more blasted off its surface by bombardment from the forming asteroid belt. Then it cooled, and a big chunk of its atmosphere froze...Martian atmospheric pressure actually varies highly depending on season, due to sublimating and freezing CO2.

In addition, the Earth's atmosphere makes an excellent shield against charged particles...there will likely be a slight increase in secondary radiation, but not enough to cause measureable effects on Earthly life.

Re:Hollywood Blockbuster?

[MissMarvel]

Or better yet, try Phil Plait's review... on his Bad Astronomy website [badastronomy.com]