Earth's center is out of sync

May 13, 2013
Earth’s centre is out of sync

(Phys.org) —We all know that the Earth rotates beneath our feet, but new research from ANU has revealed that the center of the Earth is out of sync with the rest of the planet, frequently speeding up and slowing down.

Associate Professor Hrvoje Tkalcic from the ANU College of Physical and and his team used earthquake doublets to measure the rotation speed of Earth's inner core over the last 50 years.

They discovered that not only did the inner core rotate at a different rate to the – the layer between the core and the crust that makes up most of the planet's interior – but its rotation speed was variable.

"This is the first that the inner core has rotated at a variety of different speeds," Associate Professor Tkalcic said.

"We found that, compared with the mantle, the inner core was rotating more quickly in the 1970s and 1990s, but slowed down in the 80s. The most dramatic acceleration has possibly occurred in the last few years, although further tests are needed to confirm that observation.

"Interestingly, Edmund Halley, namesake of Halley's , speculated that the inner shells of the Earth rotate with a different speed back in 1692."

Scientists have so far assumed the of the inner core to be constant because they lacked adequate mathematical methods for interpreting the data, says Associate Professor Tkalcic. A new method applied to doublets – pairs of almost identical earthquakes that can occur a couple of weeks to 30 or 40 years apart – has provided the solution.

"It's stunning to see that even 10, 20 or 30 years apart, these earthquakes look so similar. But each pair differs very slightly, and that difference corresponds to the inner core. We have been able to use that small difference to reconstruct a history of how the inner core has rotated over the last 50 years," he said.

Associate Professor Tkalcic says this new method could help us understand the role of the inner in creating the magnetic field that allowed life to evolve on Earth by acting as a shield from cosmic radiation.

"What we have developed is a very powerful way to understand the internal structure and dynamics of our planet," he said.

The research was published in Nature Geoscience.

Explore further: NASA sees Typhoon Matmo making second landfall in China

More information: Tkalčić, H., M.K. Young, T. Bodin, S. Ngo and M. Sambridge, The shuffling rotation of the Earth's inner core, Nature Geoscience, DOI:10.1038/NGEO1813 , 2013.

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VENDItardE
1.8 / 5 (16) May 13, 2013
Of course it does, what happens to a motor when loaded ? It slows down and then speeds back up as the load lessens..........the varying load could be the solar corona mass ejections that create such beautiful light shows.
nkalanaga
2.1 / 5 (8) May 13, 2013
Since the solid inner core is "floating" in the liquid outer core, it could also be influenced by Lunar, and to a lesser extent, solar, tidal forces. The Moon would slow or speed the inner core relatively quickly, then the change would be transmitted to the rest of the Earth through friction in the liquid outer core, which would take longer. Meantime, the Moon is still changing the speed of the inner core.
tadchem
1 / 5 (1) May 13, 2013
Magnetohydronamics tells us as much.
Earth has a variable magnetic field.
The fluid core *must* be rotating relative to the mantle and crust. The changes in the difference correspond to changes in magnetic field strength, with the earth's magnetic field temporarily vanishing when they ARE synchronized (difference in rotation speed = 0).
GSwift7
4.4 / 5 (9) May 13, 2013
I would investigate angular momentum rather than EM loading and tides. There's probably a powerful interaction between the internal layers that involves turbulence and convection. Like an ice skater spinning faster and slower by retracting or extending arms and legs, the core should change its rate of rotation in response to changes in density and/or temperature. If parts of the core are able to melt and join the mantel or parts of the mantel are able to condense onto the core, then the mass and diameter of the core would be variable as convection stirs the mantel. I would also expect molecular interaction between the mantel and core might trade significant amounts of energy between the mantel and core. Again, conservation of angular momentum would force a change in rotational speed. A better study of these changes in speed might indicate the source of the changes, once the magnitude is known.
Maggnus
3.9 / 5 (7) May 13, 2013
creating the magnetic field that allowed life to evolve on Earth by acting as a shield from cosmic radiation.


Should read " allowed Earth based life to evolve.." there's nothing that says there "must" be a magnetic field for life to evolve, but it's definitely needed by life that has evolved on Earth.
nkalanaga
3 / 5 (2) May 14, 2013
GSwift7: Yes, I can see your method working as well. I doubt that it's anything as exotic as an electric motor effect.
GSwift7
3.7 / 5 (3) May 14, 2013
GSwift7: Yes, I can see your method working as well. I doubt that it's anything as exotic as an electric motor effect


Well, of course we're all just guessing, but if you look at what we can see in other places, angular momentum seems to be a major driver in planetary mechanics and the mechanics of other free floating gravitationally bound fluid structures around us. For example, the observations we have of acretion disks show this kind of differentiated motion, and the math seems to add up to conservation of angular momentum. Just following the intuitive line of reasoning and applying what we observe in other places, seems to make sense. This could be totally wrong though. :)

The reason I suggest something other than EM is that it speeds back up. Angular momentum is an easy explanation for something rotating that speeds up without needing an external energy source to do so. You know the old rule regarding the simplest explanations. EM requires some energy source we don't see
GSwift7
3.7 / 5 (3) May 14, 2013
continued:

When we are talking about the core, it is important to remember that we don't know hardly anything about it. We are not able to re-create the pressure and temperature of the core in our laboratories, and we don't have any experience with materials in this regime. We have begun to suspect that there are unknown phase changes and unknown states of matter, such as semi-crystaline structures and superfluids. The core 'could' be undergoing something like a phase change. That would explain changes in density (and therefore changes in rotational speed) very nicely.
no fate
1 / 5 (2) May 14, 2013
Why not all of the above? Every factor mentioned in each post exerts some level of influence.....
GSwift7
3.4 / 5 (7) May 14, 2013
Why not all of the above? Every factor mentioned in each post exerts some level of influence.....


As I said, speeding back up is a problem for any mechanism besides conservation of momentum. In order for the core to speed back up like an electric motor driven by EM, you would need an extraordinary alignment of circumstances, and it would then be difficult to explain why it slows back down. Then you would also need to explain the energy source that powered the motor effect.

Conservation of momentum is the only means by which you can have the core speed back up without any need for an outside power source to make it turn faster. Besides, do you realize how complicated the structure and timing would need to be in order to make a motor? Have you ever tried to make your own motor for a science fair project? I don't think that explanation is very plausible.
no fate
1 / 5 (1) May 14, 2013
I was thinking you were correct on conservation of momentum being how and why it speeds back up. With perturbations of the magnetic field being what slows it down. If there were phase changes taking place, something would have to drive those changes which would indicate either large scale internal fluctuations in pressure and temperature, or the matter at the boundary between the inner and outer core being constantly on the cusp of a phase change.
cantdrive85
1.4 / 5 (10) May 14, 2013
In order for the core to speed back up like an electric motor driven by EM, you would need an extraordinary alignment of circumstances,

So, I guess that somehow suggests that it cannot happen? BTW, the "extraordinary alignment of circumstances" is met being that you have a charged body, the Earth, rotating and orbiting another charged body, the Sun, within an environment of inhomogeneous plasma flowing in and out of the Sun and Earth.

and it would then be difficult to explain why it slows back down.

Actually, the tard explained it quite well. Energy flows in, it speeds up, it flows out, it slows.

cantdrive85
1.3 / 5 (12) May 14, 2013
Then you would also need to explain the energy source that powered the motor effect.


The source would be the Sun, as they state in the article;
"We found that, compared with the mantle, the inner core was rotating more quickly in the 1970s and 1990s, but slowed down in the 80s. The most dramatic acceleration has possibly occurred in the last few years, although further tests are needed to confirm that observation.


This correlates with peaks and troughs in the solar cycle. The only mysterious phenomenon is why "scientists" cannot connect the dots, or circuits for that matter.

no fate
1 / 5 (4) May 14, 2013
It MAY correlate to peaks and troughs in the solar cycle...but even if it does, you would at that point have to discern between the effects which slow it versus those which speed it back up. If you have something, I'm interested.
barakn
4.5 / 5 (8) May 14, 2013

"We found that, compared with the mantle, the inner core was rotating more quickly in the 1970s and 1990s, but slowed down in the 80s. The most dramatic acceleration has possibly occurred in the last few years, although further tests are needed to confirm that observation.

This correlates with peaks and troughs in the solar cycle. The only mysterious phenomenon is why "scientists" cannot connect the dots, or circuits for that matter.

They're not connecting the dots because you're full of crap. The solar cycle peaks about once a decade, i.e. in the 70s, 80s, and 90s. Try using that to explain why the 80s are different from the 70s or 90s.
GSwift7
5 / 5 (4) May 14, 2013
With perturbations of the magnetic field being what slows it down. If there were phase changes taking place, something would have to drive those changes


If it is conservation of momentum speeding it back up, then it would be conservation of momentum that slows it down also. Just like a skater drawing her arms in to speed up, then sticking them back out to slow down. We are nearly certain that the core is actually two parts, the inner and outer. The outer core is probably highly convective and the material probably undergoes phase changes, effecting density and temperature. According to our best models, a few kelvin temperature difference in that kind of pressure could drive violent convection flows. Think of the phase changes that happen in a rising thunder head. From vapor to liquid to solid water, then imagine that on steroids and composed of iron and other heavy things. That is a lot of momentum.
barakn
5 / 5 (7) May 14, 2013
... you have a charged body, the Earth, rotating and orbiting another charged body, the Sun, within an environment of inhomogeneous plasma flowing in and out of the Sun and Earth.
A charged Earth. From Gauss's law, Earth's spherical symmetry, the relatively conductive surface, and the weak electric field in the lower atmosphere, there's not much charge down here. It must be above our heads. Where is this charge, and how much of it is there? After all, a good physical theory must be quantifiable.
no fate
1 / 5 (2) May 14, 2013
The study used 2 events from the 70's as part of a doublet, both were from 1970. Without a measured duration for speeding or slowing to take place, a definitive statement can't be made for the whole decade. All they know is that compared to 1970, the core rotation was slower in the 80's for which there are more data points spread out across the decade. They can't prove a cycle yet. If it is cyclical, 22 years coincides with the orientation of the suns magnetic poles. This would rule out peaks and troughs.
no fate
3 / 5 (2) May 14, 2013
With perturbations of the magnetic field being what slows it down. If there were phase changes taking place, something would have to drive those changes


If it is conservation of momentum speeding it back up, then it would be conservation of momentum that slows it down also. Just like a skater drawing her arms in to speed up, then sticking them back out to slow down. We are nearly certain that the core is actually two parts, the inner and outer. The outer core is probably highly convective and the material probably undergoes phase changes, effecting density and temperature. According to our best models, a few kelvin temperature difference in that kind of pressure could drive violent convection flows. Think of the phase changes that happen in a rising thunder head. From vapor to liquid to solid water, then imagine that on steroids and composed of iron and other heavy things. That is a lot of momentum.


True. Even a subducted plate reaching the outer core could slow it.
cantdrive85
1 / 5 (10) May 14, 2013
Where is this charge, and how much of it is there? After all, a good physical theory must be quantifiable.

It's charged (or merely differently charged) from the medium in which it is immersed, inhomogeneous solar plasma.
barakn
5 / 5 (8) May 14, 2013
So in other words, it might be positively or negatively charged, or even neutral, and you can't state even in broad generalities where the charge resides, if it exists. And we should take you seriously why?
no fate
2 / 5 (4) May 15, 2013
Where is this charge, and how much of it is there? After all, a good physical theory must be quantifiable.

It's charged (or merely differently charged) from the medium in which it is immersed, inhomogeneous solar plasma.


You do not display an understanding of all of the systems involved here, plasma included. Trying to pin this on one specific variable (I gave you the peaks and troughs only because they cant be 100% ruled out) when we don't even have enough data to confirm a cycle is premature. We are all just speculating at this point which was mentioned above. It could even be as simple as a response to the seismic vibrations of quakes themselves, at which point phase changes as a result of the vibrations put Gswift7 right on the mark.
GSwift7
4.6 / 5 (9) May 15, 2013
You do not display an understanding of all of the systems involved here, plasma included


Exactly. Cantdrive has proven many times that he doesn't understand even the basics of EM theory, or any other. IF he did, he would understand why his proposed planetary dynamo is impossible. It's actually really funny.

He's actually contradicted himself, but I doubt he would understand how, even if I try to explain it.

I'll bet you will catch his mistake right away:

He has claimed many times before that the Earth's magnetic field is generated by the electric currents inside the earth. Then here he is saying that the changes in the rotation of the Earth's core are caused by changes in the ambient magnetic field of the sun. lol. I'll bet he can't figure out why those two things can't both be possible at the same time. I think they teach that in sixth grade now, don't they? Magnets and circuits and such?

Hey, cantdrive, where's the web site to buy one of your perpetual motion machines?
no fate
4 / 5 (2) May 15, 2013
Dynamo driven EM fields do not have a cathode or anode in the circuit sense, which are a must for current. The field is a result of magnetohydrodynamics as Tadchem stated above. The first post mentioned CME's which could effect the dynamo motion if they could apply enough magnetic pressure to the field this motion generates. But the more I think about it I like your hypotheseis better. The kinetic energy released inside the core from a field pertubation strong enough to effect it would likely be felt on a global scale. A core quake if you will.

cantdrive85
1.3 / 5 (13) May 15, 2013
I'll bet you will catch his mistake right away:

He has claimed many times before that the Earth's magnetic field is generated by the electric currents inside the earth.


Ha! Do you understand how to read? Is there meaning to words? Not sure wen I claimed the dynamo effect created a magnetic field, as a matter of fact I have repeatedly mocked the idea. But you'd have to comprehend words to catch on.
no fate
4.7 / 5 (6) May 15, 2013
not sure wen I claimed the dynamo effect created a magnetic field, as a matter of fact I have repeatedly mocked the idea.


You have just proven that you don't understand the systems you are commenting on. Bodies like mars and the moon lack a magnetic field because they lack differentiated layers moving at different velocities. All bodies that have this produce an external field.

What do you think a planetary dynamo does?



GSwift7
4.3 / 5 (11) May 15, 2013
Not sure wen I claimed the dynamo effect created a magnetic field, as a matter of fact I have repeatedly mocked the idea


No, I didn't say that you supported the dynamo effect. You support some imaginary theory of your own that has something to do with electric currents inside the Earth which create the Earth's magnetic field. This current is supposedly due to the fact that space has plasma in it.

Now you're saying that the space plasma is also responsible for the core slowing down and speeding up, which implies that it is the reason the core spins at all.

You can't have both of those ideas at the same time. I know you don't see why, but trust me.

NoFate, yes I know. No cathode or anode. Cantdrive's problem is that his previously stated fantasy theory would conflict with his currently stated fantasy theory because he has A powering B and B powering A. Don't worry about him. He says the grand canyon is caused by a lightning bolt from space and volcanos too, right?
cantdrive85
1.3 / 5 (12) May 15, 2013
You have just proven that you don't understand the systems you are commenting on. Bodies like mars and the moon lack a magnetic field because they lack differentiated layers moving at different velocities. All bodies that have this produce an external field.

What do you think a planetary dynamo does?

So says the standard THEORY. The in situ observational and laboratory data are quite lacking. However, the observational and laboratory data in re to faraday motors is quite extensive.
Here are a couple of snippets that explains how this electromotive force works.
http://www-spof.g...wio.html
ftp://space.mit.e...umbs.pdf
Note the Earth's rotation gives it additional electromotive force, as such a stronger magnetic field. Mars only has a tenuous atmosphere (plasma DL) because it is largely equalized to its environ.
cantdrive85
1 / 5 (10) May 15, 2013
No, I didn't say that you supported the dynamo effect. You support some imaginary theory of your own that has something to do with electric currents inside the Earth which create the Earth's magnetic field. This current is supposedly due to the fact that space has plasma in it.

You are delusional. That is your own misguided imagination running wild. There are no doubt electric currents that flow through the Earth, telluric currents are indeed part of the overall magnetospheric circuit, just as electric currents flow through the coils of an electric motor.

"So astounding are the facts in this connection, that it would seem as though the Creator himself had electrically designed this planet..." Tesla

NoFate, yes I know. No cathode or anode.

Always the referring to the fallback. The problem you have is a misunderstanding of plasma circuits and how plasma double layers enable these currents.
ValeriaT
3 / 5 (2) May 15, 2013
inglenook_hampendick
2 / 5 (4) May 15, 2013
What's amazing is how so many believe unquestioningly what they read. Critical thinking is pretty much a thing of the past.
no fate
5 / 5 (3) May 16, 2013
The problem you have is a misunderstanding of plasma circuits and how plasma double layers enable these currents.


The problem you have is that there is no plasma inside the earth so you need to have understanding of other sciences to speak intelligently about this system. The articles you have linked regarding the Jupiter/Io system deal with phenomena only applicable to that system, I had read Belcher's paper and liked it, alot of his theory has been confirmed by observation, but the earth/sun/moon system is very different.

Particle and current density are orders of magnitude smaller than they need to be for the effects you attribute to plasma.
cantdrive85
1.3 / 5 (9) May 16, 2013
Particle and current density are orders of magnitude smaller than they need to be for the effects you attribute to plasma.

And the size of Earth's EM field are orders of magnitude larger as well. The main difference between the IO-Jupiter vs. Sun-Earth connection is the ease of observation. As you mention, the particle/current density is much higher, as such the phenomenon are much easier to observe and monitor. Here is a couple articles on the Sun-Earth connection;
http://www.nasa.g...als.html
http://science.na...tbreach/

Here are a couple articles that describe the similar phenomenon for some other planets/moons.
http://www.nasa.g...oes.html
http://www.resear...nd_Titan

The Sun is connected to it's planets, just as Io and Jupiter are.

no fate
5 / 5 (4) May 16, 2013
Your last post and links are accurate information. It is your interpretation of the effects these variables produce that is incorrect. In the case of this article, a core rotation rate driven by energy from the sun would be the sole factor driving the rotation for the effects observed in the article. This was stated above by Gswift. The same satelites in your links would detect this easily, instead they detect intermittent portals, shortlived flux ropes and particle scattering in the magnetosphere. There is no energy following magnetic flux lines through the ionosphere, the atmosphere, crust and mantel to the outer core.
Shelgeyr
1.7 / 5 (6) May 17, 2013
It's stunning to see that even 10, 20 or 30 years apart, these earthquakes look so similar. But each pair differs very slightly, and that difference corresponds to the inner core.


Even if that ultimately proves out to be true, at this stage of the game they have no business presenting that second sentence as fact. They can feel free to take it as part of their assumptions, of course, but let's be clear that it is part of their hypothesis - not an established fact.
exequus
2.3 / 5 (3) May 20, 2013
I've always suspected that something was slightly misaligned in Mother Earth's machinery but of course, that was just a hunch, couldn't have provided empirical evidence.
swordsman
1 / 5 (2) May 20, 2013
Perhaps the center of the earth is not exactly the center of rotation. Moving tides could produce such an effect.