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Posted on 06/16/2009 9:29:47 AM PDT by BGHater
A radical new idea may revolutionise our understanding of one of the most vital forces on Earth
Earth's magnetic field, long thought to be generated by molten metals swirling around its core, may instead be produced by ocean currents, according to controversial new research published this week.
It suggests that the movements of such volumes of salt water around the world have been seriously underestimated by scientists as a source of magnetism.
If proven, the research would revolutionise geophysics, the study of the Earth’s physical properties and behaviour, in which the idea that magnetism originates in a molten core is a central tenet.
Earth’s magnetic field is vital for life, extending tens of thousands of miles into space and protecting the planet against radiation that would otherwise burn away the atmosphere and oceans.
However, its origin was a mystery until early last century when Albert Einstein said understanding the phenomenon was one of science’s most important tasks. This provoked a debate which concluded with scientists agreeing that magnetism must originate in the Earth’s core.
“Everyone accepted this, but in reality there has never been any proof,” said Gregory Ryskin, associate professor of chemical and biological engineering at Northwestern University in Illinois. “It is just an idea we have accepted for a long time without questioning it enough.”
His research suggests that Earth’s magnetism is actually linked to ocean movements. The salt in seawater allows it to conduct electricity, meaning it generates electrical and magnetic fields as it moves.
The findings, published by Britain’s Institute of Physics’s New Journal of Physics, will cause a fierce scientific debate.
(Excerpt) Read more at timesonline.co.uk ...
‘If Ryskin is right, then climate change, predicted to alter the strength and course of ocean currents, could also alter the planet’s magnetic field. ‘
Catastrophe or hollow earth ping.
Interesting theory.
Seems a bit too easy to test, however, for someone not to have discovered it before.
Although perhaps not the core mechanism, a bunch of free ions swarming across magnetic lines are going to alter or create fields otherwise not extant.
Good to see the idea coming out of the US. We're losing it fast - all lawyers, no science. Kind of like Barack Obama, Hillary Clinton, Charles Schumer, Barbara Boxer, Nancy Pelosi, Rahm Emmanuel, etc. etc. etc.
Expect this to be the newest battlefront with the global warming nutjobs.
Diameter of earth at equator = 7926 miles
radius of earth at equator = 3963 miles
Volume of earth = 4/3*pi*R^3 = 260,711,886,825 cu mi
Assume average ocean depth of 2.7 miles (based on size and average depth of each ocean) and water coverage of 71%
Volume of ocean = 71%*4/3*pi*(3963^3 - 3960.3^3)
= 71%*4/3*pi* (62240377347-62113250509)
= 71%*4/3*pi* 127126838
= 71% * 532507661
= 378080439 cu miles
Ratio of Ocean to Earth volume
= 378,080,439 / 260,711,886,825 = .145%
Ratio of solid Earth to Earth volume = 99.855%
I would think the effect of such a small percentage of the earth's mass would have a neglible effect on earth's magnetic fields.
Anyone else have any thoughts?
This would suggest that it’s the crust that is magnetized, which may in turn magnetize the core? Interesting. I have no idea what to make of this.
It is at least refreshing that, even if they’re wrong, there are some scientists out there questioning even the most very basic of “conventional wisdom” tenets of science. That’s a healthy thing.
How far down is the molten core?
And what would it’s volume be compared to the ocean’s?
"Iron is the sixth most abundant element in the Universe, formed as the final act of nucleosynthesis, by silicon fusing in massive stars. While it makes up about 5% of the Earth's crust, the Earth's core is believed to consist largely of an iron-nickel alloy constituting 35% of the mass of the Earth as a whole. Iron is consequently the most abundant element on Earth, but only the fourth most abundant element in the Earth's crust.[4] Most of the iron in the crust is found combined with oxygen as iron oxide minerals such as hematite and magnetite."
I don't think it is too much of a stretch to say that a magnetic element that is 35 times more prevalent in earth's crust than water and which rides on top of a core that is 35% iron-nickel contributes more to our magnetic field than do ocean currents.
I'm inclined to agree with other posters who see this theory as a new line of attack in the global warming "debate"
My retort is that the earth has had numerous ice ages and warming spells, and the ice caps have formed and melted manifold times, disrupting ocean currents, yet the earth has always seemed to muddle through somehow.
In response to your closing, I don't see it as hopeful, except in the sense that the scientists proposing this theory are "hoping" for some of my taxpayer dollars to fund additional "research". In most societies, prostitution is illegal; in all, it is immoral...YMMV ;)
Way before approaching the depths where the core is molten, iron would be above it’s curie temperature and would no longer be magnetic.
Appears that the inner core is 750 mi in diameter, surrounded by an outer core that is 1400 mi thick.
Applying our volume formula:
Volume of core = 4/3 * pi * r^3
= 4/3 * pi * (1400 + 750/2)^3
= 4/3 * pi * 5592359375
= 23,425,252,581 As a percentage of the earth's volume, the core is
= 23,425,252,581 / 260,711,886,825
= 9%
I metal detect and the movement of salt water definitively generates electric fields. It affects the fields put out by metal detectors enough that you have to have a certain type or at least have the right settings. It makes sense. There’s an awful lot of sea.
Remember that the inner core is solid. If there is no motion present in the inner core, I don’t believe that it contributes to the creation of the magnetic field.
Good point, Iron is unusual stuff, just looking at a T3 chart it’s all about the carbon content vs the molecular
structure. Once the carbon is no longer trapped in the lattice it’s no longer magnetic.
And to think our whole society is built of the stuff...
According to link from other post in this thread, the earth's crust is 20 mi thick on average under the continents and 3 mi thick on average under the oceans. Using the 71% ocean ratio, we get the average thickness of the crust is 7.93 miles; applying our formula for volumes, the volume of the crust would be:
Volume crust = 4/3 * pi * (r1^3 - r2^3)
= 4/3 * pi * (3963^3 - 3955.07^3)
= 4/3 * pi * (62240377347 - 61867493758)
= 4/3 * pi * 372883589
= 1,561,931,148 cu miles
From earlier post, volume of ocean = 378,080,439 cu miles
Ratio of solid crust to ocean = roughly 4/1 (earth's crust is approximately 80% solid and 20% water)
If 5% of crust = Fe, then there is 4% iron in crust compared to 20% water (5:1 ratio); ignoring the negligible amount of iron dissolved in seawater (< 10^-9 moles/kg), I still think the magnetic properties of the iron would have far greater effect on earth's magnetic field than the electrolytic/conductive properties of sea water - what are your thoughts?
Agreed that there is a lot of sea, but I think, volume-wise, it is dwarfed by the volume of the crust (see calculations in posts above).
I don’t believe that the solid crust contributes to the creation of the magnetic field. I think it’s creation is due to the motion of the molten conductive iron in the liquid portion of the Earth’s core.
Jupiter, Saturn, Uranus, and Neptune all have magnetic fields too, but are all gas giants and not really comparable.
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Gods |
Thanks BGHater.Earth's magnetic field, long thought to be generated by molten metals swirling around its core, may instead be produced by ocean currents, according to controversial new research published this week. It suggests that the movements of such volumes of salt water around the world have been seriously underestimated by scientists as a source of magnetism.To all -- please ping me to other topics which are appropriate for the GGG list. |
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