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Ocean Currents Proposed As Cause of Magnetic Field
pjt33 notes a recently published paper proposing that ocean currents could account for Earth's magnetic field. The wrteup appears on the Institute of Physics site; the IOP is co-owner, with the German Physical Society, of the open-access journal in which the paper appears. This reader adds, "The currently predominant theory is that the cause of Earth's magnetic field is molten iron flowing in the outer core. There is at present no direct evidence for either theory." "Professor Gregory Ryskin from the School of Engineering and Applied Science at Northwestern University in Illinois, US, has defied the long-standing convention by applying equations from magnetohydrodynamics to our oceans' salt water (which conducts electricity) and found that the long-term changes (the secular variation) in the Earth's main magnetic field are possibly induced by our oceans' circulation."
There is enough junk floating on the oceans that the currents could be ferrous.
So basically we know that global warming has taken over our ocean's currents when our compasses start pointing to the south...
The Core was just a bunch of non-scientific crap.
Aren't there planets that do have magnetic fields, but don't have oceans? And aren't there moons that are the opposite case?
At the bottom of the
Yeah, that makes a whole hell of a lot of sense. Why not invent some brand new, goofy theory that applies only to the Earth and not to any of the other celestial bodies that we know have magnetic fields which DON'T have oceans? Has somebody never heard of Occam's Razor? Instead of one theory which works to explain all magnetic fields on all celestial bodies why not invent something stupid for no good reason?
Fascinating! If true, I wonder how it could effect theories on terraforming. If we got enough open and moving water on Mars could it then develop the field needed to block solar radiation and trap an atmosphere?
The Slashdot summary is totally wrong.
From the abstract of the paper: "I propose a different mechanism of secular variation: ocean water [...] as it flows through the Earth's main field may [...] manifest itself globally as secular variation."
Meaning: There is a major magnetic field that comes from the molten core. However, certain variations that are as yet unexplained may not result from core phenomena, but from the ocean currents.
I find this much more believable than the swill in the slashdot summary.
Bunk.
Wouldn't explain magnetized rocks, magnetic north, etc...
Well, relativity simply solved.
All we need to do is find an object that has a magnetosphere and no aqueous sea.
How about the Sun?
Comment removed based on user account deletion
He predicted Global Warming...shocked the world with "An Inconvinient Truth"...and created the internet.
This can only mean one thing: Al Gore is the Messiah. Move over Obama, there's a new kid in town.
"The difference between genius and stupidity is that genius has it's limits" - Albert Einstein
Read above.
Ocean currents are /NOT/ being proposed as a cause of the magnetic field.
The headline is a lie.
While I have no expertise in this area ... Are ocean current patterns really as static as the Earth's magnetic field? I'd think that there would be more fluctuations/variations in the Earth's magnetic field if it depended on the waterbodies. Wouldn't this also require compasses / magentic fields being disrupted when there are earthquakes/tsunamis or major storms?
Just last night there was an interesting show on television that focused on the subject of magnetic fields associated with planets.
There was an experiment covered in the show that was essentially a large, hollow orb filled with liquid sodium (a substitute for the iron at Earth's outer core. It is impossible to reproduce the pressure and heat of our Earth's guts in such a small scale experiment) which was then spun at a comparatively equal rate to that of Earth. The orb began producing strong magnetic fields.
I somehow doubt that if the same experiment were to be reproduced solely with a thin layer of salt water on the surface (and no sodium inside) that it would produce such strong magnetic fields. That being said, while the thought of Earth's magnetic field being produced solely by the water on the surface is interesting, personally I think it is more then likely a combination of the two factors rather then one alone that produces our protective magnetic field.
In addition, I wonder if the flux in ocean water levels, historically speaking, coincides with the strength and direction of past magnetic fields as recorded in ancient lava flows. If so, this would seem to back up the theory proposed in the article.
The paper does not say that ocean currents cause the magnetic field. It hypothesizes that ocean currents cause secular variations in the magnetic field.
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
We might have proof of this in the foreseeable future. If we keep warming up the planet, it's quite possible that one or more major ocean currents will start behaving differently. If that happens and we see a change in the magnetic field, that would provide a strong hint that the two are connected in some way.
I've calculated my velocity with such exquisite precision that I have no idea where I am.
Wow, that's quite the fish story. Pretty interesting hypothesis though it needs solid, er, liquid evidence to back it up... otherwise it's flowing into the dust bin, er, drain of science history as a pretty darn cool and silly theory that didn't make it.
Well actually he's saying that there is a "main field" and that the ocean currents are a modification or additional field. Cool. Cutting edge science can be fun. It's where cross currents of ideas and beliefs mix until evidence eventually coalesces with a vortex pulling everyone to the indisputable conclusions - if you're lucky and on course of course.
I wonder if this hypothesis might explain the "magnetic anomalies" in the oceans around the world that are constantly changing? I'd love to see a three dimensional simulation of the raw data collected by the magnetic sensing satellites and the gravity satellites correlated together with ocean current movements.
Does this theory spin the other way in the southern hemisphere?
Note how this dishes the favorite argument of pseudoscientists, who always (always, always) claim that the scientific "establishment" refuses to hear evidence that conflicts with accepted wisdom. Rather - to the extent that such an establishment can be said to actually exist - science will entertain any sort of extreme argument, as long as it is cogently - and entertainingly - presented. To overturn competing theories extreme arguments ultimately demand extreme evidence, however.
Ocean currents? Here's an even better idea : winds! I know it's true because when I throw a fridge magnet in the wind it goes in the same direction. So next time you want to know in what direction the wind is going, just look at a magnetic compass!
You just got troll'd!
... and I mean that literally. I'm a big fan of space research, but maybe we should also be working on an expedition (or Journey, if you will) to the Centre of the Earth. Or at least find a way to take samples and readings down there. Humanity has never dug deeper than 12,262 meters(*), and although I see the obvious problems in digging for lava, I'm convinced it would yield interesting results.
(*) This number was taken from the following article, about a Russian digging experiment: http://www.damninteresting.com/?p=567
And I'll just post this here too: http://en.wikipedia.org/wiki/Integrated_Ocean_Drilling_Program
I'd rather you rationally disagree than irrationally agree.
To be certain, there are NO 'theories' for Earth's magnetism, only a variety of HYPOTHESIS'S.
Once again the term theory is being misused for HYPOTHESIS. It is a great disservice to science and scientists to not understand the definition and implications for both terms.
A worker whose research achieves the level of Theory is among the 'Nobel class' of scientists. Therefore the term should be used properly and with some reverence.
So before we go any further, would someone venture to post the scientific definitions and usage for these two terms, hypothesis and Theory.
Thanx
the general argument here is that other planets lacking oceans also have magnetic fields-- so that ain't right..
so I'm thinking, what do all solar bodies have in common that could be another means to that end
solar wind? the flow of all the radiation from the sun, wrapping around the planet, and blowing on? happens to all objects in the system??
every day http://en.wikipedia.org/wiki/Special:Random
Too soon?
That I can no longer believe the science in that truly awesome movie The Core?
Imagine...Global warming melts the polar ice caps, the sea rises, the earths sea currents change which in turn effects the earths magnetic field. What a crazy thought...our pollution could change the direction of North.
Funny words from someone who used rather massive ad hominem by trying to label people disagreeing with him as zealots.
Consensus is used as an argument because not all of us can be climate scientists. There is large consensus among them that global warming is happening and caused by men. Not all agree to that. Name any theory and you have people who disagree with it. Hell, there is even a flat earth society. But big majority of the expert who know about the subject and have studied it their whole lives believe so.
Most of the people who argue about it in the internet aren't climate scientists. They've read a few stories which have quoted some climate scientists who disagree with the mainstream and then begin arguing. To them I can always answer "Hey, I am not an expert in the field. And honestly, most likely you aren't either. When your arguments are good enough that they manage to sway opinions of the expert, then you can come back to me. Otherwise I have all the reason to assume that there is some flaw in them."
All of us who aren't experts in every field of science have to do that about some subjects. Trust the scientific method and through that, the experts who employ it.
This link to an article on NPR, http://www.npr.org/templates/story/story.php?storyId=90947943, was also in a short show on the Science Channel about magnetic fields. So, I think that the reader should not state that there is no evidence that the molten inards of the Earth are not the probable cause of our magnetosphere.
Good is never enough, when you dream of being great!
Could this be an explanation for the Bermuda triangle?
While I have no expertise in this area ... Are ocean current patterns really as static as the Earth's magnetic field?
Yes. Neither are static, both change continuously, but both are relatively slowly changing phenomena.
I'd think that there would be more fluctuations/variations in the Earth's magnetic field if it depended on the waterbodies.
On geological timescales, it would change dramatically. Which, we know, it does.
Wouldn't this also require compasses / magentic fields being disrupted when there are earthquakes/tsunamis or major storms?
No, since large-scale ocean currents are not noticeably affected by these things.
"Convictions are more dangerous enemies of truth than lies."
Perhaps the change in ocean currents instead of causing the change in magnetic poles is instead caused by the change in the earths magnetism. Just because something is correlated to something else does not mean it is caused by it, the opposite could be true and plenty of other relations are possible.
TFA and the Slashdot summary are both wrong. The paper doesn't allude that the ocean causes the field. It says that the field is affected (modulated) by the oceans. So the earth could be a permanent magnet, with some of the changes in its field explained by the ocean currents.
Excuse me, but please get off my Pennisetum Clandestinum, eh!
If ocean current can do the work, telephone can do it too. With people usually calling in the direction from east to west because of timezone differences, the electric current generates magnetic flux and etc. (Other examples: highway, sewage, ...)
I'm highly skeptical of this idea for one reason. The volume of the oceans is MINISCULE compared to the volume of the outer core. In order for the oceans to generate the kind of magnetic field the Earth has, they would need to be highly magnetic. Steel ships orient themselves to the currents automatically type levels. The Earth we see is a wafer-thin skin on the massive iron/nickel mass that is the Earth
This is ridiculous! Everyone knows that Jesus put the magnetic field there to test us! Science is the devil!
I attended a lecture (probably ten years ago at this point) in which he suggested particular mass extinction horizons in the geological column were the result of methane hydrate eruptions. I can't recall the specifics, other than the general disbelief of most of us in the room, on his particular hypothesis. It required a lot of specific proofs that weren't there. There was much discussion on the existence of C60 in various ash levels. And that's all I can remember, other than thinking Gregory Ryskin needs to provide stronger evidence to this hypotheses. But seriously, some of the leading paleontologists and paleoclimate people really thought his stuff was ignoring strong evidence.
FWIW, Mars used to have water and may have at one point had a stronger magnetic field than the Earth
Actually, somebody published a paper this week that suggested that Earth's magnetic field might actually accelerate our loss of atmosphere relative to Mars. In fact, Earth right now is leaking atmosphere faster than Mars is, pound for pound. The ionosphere follows the magnetic field lines high up into space, and then the sun just whisks it away.
If this paper and the OP paper stack up, I'd say a good chunk of what we know about the atmosphere just got pissed on.
This is my sig.
I guess the question here, is how much water is in the mantle? It seems like volcanic plumes from pretty deep within the earth's crust and below have -steam- pressure in them. One has to wonder if the earth is rather like a giant sponge...a big chunk of rock, yep, but saturated with water.
This is my sig.
Imagine a puddle waking up one morning and thinking, 'This is an interesting world I find myself in, an interesting hole I find myself in, fits me rather neatly, doesn't it? In fact it fits me staggeringly well, must have been made to have me in it!' This is such a powerful idea that as the sun rises in the sky and the air heats up and as, gradually, the puddle gets smaller and smaller, it's still frantically hanging on to the notion that everything's going to be alright, because this world was meant to have him in it, was built to have him in it; so the moment he disappears catches him rather by surprise. - D. Adams.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
I am confused. The discovery channel showed a huge experiment done my scientists showing that liquid metal circulating due to the earths rotation would cause a magnetic field. They did this by taking sodium and spinning it in a sphere and it produced a magnetic field. How is this not proof ?
How does this explain the magnetic fields on Mercury, Jupiter and Saturn?
He also says:
I think Mr. Ryskin is well aware that he hasn't presented enough evidence to refute the prior hypothesis. He's only pointing out that secular variation has been considered important evidence supporting the dynamo theory. An alternate explanation for the variation wouldn't necessarily falsify the dynamo theory, but it could take away supporting evidence.
But he is correct that this should stimulate further research. His paper mentions enough analytical simplifications and limitations in the source data to suggest thesis topics for an army of grad students. I'm sure there will also be much thought about how the dynamo hypothesis might be independently confirmed.
This would mean that the science in "the core" was even more wrong? I didn't think it was possible!
Good lord, the summary in this post completely mauled the meaning of the actual article.
look it up yourself asshole.
This is a ploy to make global warming, that can change oceans currents supposedly, look more dangerous.
I think this scientist was mixing crack in his testing solutions. Of course when you are on the ocean traversing a ridiculously large ocean current your compass goes nuts because the influence is in close proximity to said ocean current, and thats why commerical divers often get lost. If there is an influence on the earth's magnetic field, it's so pathetically small that my collection of fridge magnets will have an equal effect. Humourous..thanks for the laugh.
Let's hope he has a good think about anthropogenic CO2 and evolution and reaches similarly correct but against-the-mainstream conclusions.
Earths magnetic field is big (compared to, say, Mercurys, Venus' or Mars'). And compared to the mass of the planet, the oceans are tiny, shallow puddles on the surface. If I were to bet, my money would still be on the "molten iron currents" hypothesis.
Trolling for what? - The huge number of religous freaks on slashdot?
I'm sick of patronising religious nuts "feeling sorry for me because jesus is not in my life", in other words it was a reverse premptive flamebait with a 180deg religious twist (standard difficulty rating - 666).
On a more serious note: I submit the doctrine of vicarious redmptiom via human sacrafice is utterly immoral
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
planes are non-ferrous aluminium.
Stupidity is its own reward.
I think this is the correct line. The question is then where does the current come from. For that we look a the Aurora. The magnetic field reaches into space and the charged particles from space seperate and enter the atmosphere at the earth's magnetic poles. The current generates a magnetic field, which seperates the charges in the solar wind. How much currnet? Take a look.
http://www.gi.alaska.edu/ScienceForum/ASF5/506.html
This makes more sense to me than a little salt water on an extremely thin crust of the planet.
The truth shall set you free!
His summaries are made of suck, as are his headlines, you might want to look at the article itself.
The actual theory is that the ocean causes secular variations in the magnetic field, not that oceans generate the magnetic field on their own.
During an ice age, most of the Earth's oceans freeze.
Less water, less currents. (duh...)
If there's less current, there's less magnetic field.
If there's less magnetic field, the solar wind hits the planet harder.
The thing is: if during the last billion years 90% of the time the Earth was living an Ice age, the magnetic field would be significantly weaker. Shouldn't the solar wind severely affect the planet ?
I dont't think a "thin" layer of about 6 km of salty water would have a dominant influence in the planet's magnetic field.
It seems a lot more plausible to me that a convective (due to plate tectonics) thick mantle of thousands of km and a ferroneus core are the real cause of the magnetic field.
We have proven the existence of a molten outer core inside the Earth, and the proof doesn't depend on the magnetic field, but rather, seismology. Sound and vibration can travel in any substance as a pressure wave - material compressing and decompressing (P-waves). In solids, vibration can also be orthogonal to the direction of propagation (S-waves). Think of vibration in a string, or in a tuning fork. It is known empirically that S-waves travel through the Earth only to certain depth. Because they can't propagate deeper than that, the material must be unsuitable for S-waves, which means liquid.
Now, if there's a liquid, a gravitational field, and a temperature difference, convective flow must be present too. In addition, this liquid outer core is circulating around the Earth's axis. So the "geodynamo" still seems like the best explanation to me (I recommend Fowler's The Solid Earth if anyone's actually interested in the science and reasoning behind all this).
the long-term changes (the secular variation) in the Earth's main magnetic field are possibly induced by our oceans' circulation.
This here is what the article actually states. I'm not surprised that oceanic currents can correlate with the details of the magnetic field, as the field is known to be the result of several phenomena. Actually this finding can turn out to be supporting the geodynamo idea, as one problem with the geodynamo is why the magnetic field is such a mess ;). Maybe core currents generate most of the magnetic field and oceans add variation to it.
Oooooo-kay... so the article claim that this could be possible because "water can conduct electricity"... so WHERE is this water-borne electricity coming from, then? We have a magnetic field that surrounds the whole planet, wouldn't that turn the entire ocean's wildlife into fishsticks? Also, when you run electric current through water (such as when you set up a simple electro-plating rig) wouldn't that run nearby compasses nuts?
And here all this time I thought the Bremuda Triangle was just a clipping error in Gods video game !
Wanna fight ? Bend over, stick your head up your ass, and fight for air.
... there was little salt, and little conductivity, in the oceans. Where does the remnant field in the rock come from?
Richard Feynman tells me the earth carries a large negative charge, daily replenished by lightning. This rotates at a mean speed. Will this rotating charge not give (some of) us what we want? - Roger -
More likely the salt is following the magnetic flow, rather than the other way around.
Don't recall the show, just saw something on one of the science channels wherein some scientists made a planetary model (a big rotating ball of liquid sodium around a free-floating iron ball), their theory being it is the rotational difference between the outer molten core and the solid inner core that causes our magnetic field. In the model, once the thing came up to speed, it generated a field similar to the Earth's magnetosphere.
Also, the field has reversed itself (pointing in to the planet, allowing radiation in, rather than keeping it out) many times. Just check out cores from any long-standing lava flows. We seem to be starting another flip, partially evidenced by holes in our magnetosphere ( ahref=http://news.slashdot.org/article.pl?sid=08/12/17/2352243/rel=url2html-31969http://news.slashdot.org/article.pl?sid=08/12/17/2352243/> ).
If this rotational difference is in fact where our magnetic field comes from, tinfoil had mode says exploiting geothermal energy is ultimately a no-no. Go solar!
You could at least read the paper. It doesn't talk about the oceans being responsible for the magnetic field, or even part of it. It talks about non-periodic variation in the magnetic field. So you actually need a magnetic field to start with, likely produced by the molten core. This paper is very rational and the correlation with ocean flow-intensity is quite good.
This doesn't mean he is right: ocean flow intensities could be tightly regulated by the magnetic field. However an interesting claim is the link between Europe climate variation and magnetic variation. Think about that: before this paper, no one would have argue that the mantel core was responsible for Western Europe historical climate variation. Wether this guy is right or wrong, he does bring a very interesting idea that will branch to many other interesting aspects. Itâ(TM)s worth investigating.
unless it was a very thick and/or sturdy paper bag, but a wooden bark bowl that will burn quite nicely on a fire will, if there's water in it, remain unburnt and boil the water no problem.
You can do the same with leaves.
The paper bag probably has too mobile a structure for water (with the exposed short lignin tubes made by pulping wood), but if you had a wide shallow bowl and a wide heat source so that the wet bag and the hot air don't depart from each other all that much, you'd be able to do it in a paper bag too.
NOTE: you have to top up the water in the bark bowl or lift it as the water evaporates to keep it from burning.
Recently I heard of a study that showed a major change in the way ocean water flows from one hemisphere to the other is a significant factor in warming data. I'd believe small variations but not the entire field coming from the ocean. That said it might need to be considered regarding aerospace and naval systems.
If you mean the experiment at Dan Lathrop's Nonlinear Dynamics Lab, they are doing succesive experiments with bigger and bigger spheres. Last was with a 60cm one, and now they are working on the 3m version which is the one with 13.5 tons of sodium as you mention. According to their webpage:
There is an article about them from 2008 at Universe Today, and also other people in France were doing spinning sodium experiments in 2007.
There's a chilean cable provider that seems to have been inspired by the Slashdot logo.
I wonder if he might have it backwards. Perhaps the ocean currents are influenced by the earths magnetic field, not so much the other way around.
So one would have correlation, just not in the way posited here.
Shop smart, Shop S-Mart.
The image with the article has the poles of the magnetic field wrong.
The title and summary gets this paper all wrong. It does not propose that ocean currents are causing the earth's magnetic field. In proposes that many of the small scale variations of the field is caused by variations in ocean currents. The main field is still produced by the core.
Why do the magnetic poles in the picture come out through India and the Atlantic ocean?
--
We're overdue now by several thousand years.
Not to sound ignorant, but why is it that we're overdue for:
We're overdue for everything, such that, I'm overdue for some coffee.
I know it's Monday morning: don't worry about being late.
Not all. Some planes are fiberglass (Piper Tomahawk). Some are aluminum. Some are wooden. Some are quite ferrous welded steel cages with a dope and fabric covering.
"People who think they know everything are very annoying to those of us who do."-Mark Twain
This should have appeared as a preprint on the xxx archives first, if it wants to be taken seriously. I see a bunch of math, and a disjointed argument. That sounds alarm bells in my head. I would not really pay close attention to this article until it was cleaned up and resubmitted and/or I heard the author present his ideas live, with the ability to ask questions and get clarifications.
Fixed that for ... me, really, and my entertainment. :)
I feel fantastic, and I'm still alive.
Here ya go, there is a "part two" in the related video's sidebar.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
I don't know why this hasn't been out there for the last century. Pfaw to global warming, this is a real viable theory with reason to explore further. It doesn't mean we toss the theory of a ferrite core which is a natural dipole, but we can examine the strength of the magnetic field taking into account an electronic current running through the fluid currents that "wrap" around the core. For anyone with a strong background in geology, is the current magnetic field explicable with just the ferrite core, or is it too strong? If so, the electrons that move with the currents can explain the increase. If not, then maybe the currents are a result of the magnetic ferrite core...
Commercial passenger planes?
Yes, I caught the 2:30 transatlantic flight to Frankfurt aboard a Piper Tomahawk?!
Stupidity is its own reward.
Basically, the newspapers took what the paper said, and extrapolated to an obscene extent. The author of the actual research disavows almost the entire news article outside of having a theory, and it involving oceans and magnetism.
http://www.guardian.co.uk/commentisfree/2009/jun/20/bad-science-magnetism-ocean-core
Complete BS
Bureaucracy expands to meet the needs of the expanding bureaucracy.-Oscar Wilde