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Earth's core rotating faster than rest of the planet but slower than previously believed
University of Cambridge ^ | February 20, 2011 | Unknown

Posted on 02/21/2011 4:47:12 PM PST by decimon

New research gives the first accurate estimate of how much faster the Earth's core is rotating compared to the rest of the planet.

Previous research had shown that the Earth's core rotates faster than the rest of the planet. However, scientists from the University of Cambridge have discovered that earlier estimates of 1 degree every year were inaccurate and that the core is actually moving much slower than previously believed – approximately 1 degree every million years. Their findings are published today, Sunday 20 February, in the journal Nature Geoscience.

The inner core grows very slowly over time as material from the fluid outer core solidifies onto its surface. During this process, an east-west hemispherical difference in velocity is frozen into the structure of the inner core.

"The faster rotation rates are incompatible with the observed hemispheres in the inner core because it would not allow enough time for the differences to freeze into the structure," said Lauren Waszek, first author on the paper and a PhD student from the University of Cambridge's Department of Earth Sciences. "This has previously been a major problem, as the two properties cannot coexist. However, we derived the rotation rates from the evolution of the hemispherical structure, and thus our study is the first in which the hemispheres and rotation are inherently compatible."

For the research, the scientists used seismic body waves which pass through the inner core - 5200km beneath the surface of the Earth - and compared their travel time to waves which reflect from the inner core surface. The difference between the travel times of these waves provided them with the velocity structure of the uppermost 90 km of the inner core.

They then had to reconcile this information with the differences in velocity for the east and west hemispheres of the inner core. First, they observed the east and west hemispherical differences in velocity. They then constrained the two boundaries which separate the hemispheres and found that they both shifted consistently eastward with depth. Because the inner core grows over time the deeper structure is therefore older, and the shift in the boundaries between the two hemispheres results in the inner core rotating with time. The rotation rate is therefore calculated from the shift of the boundaries and the growth rate of the inner core.

Although the inner core is 5200km beneath our feet, the effect of its presence is especially important on the Earth's surface. In particular, as the inner core grows, the heat released during solidification drives convection in the fluid in the outer core. This convection generates the Earth's geomagnetic field. Without our magnetic field, the surface would not be protected from solar radiation, and life on Earth would not be able to exist.

"This result is the first observation of such a slow inner core rotation rate," said Waszek "It therefore provides a confirmed value which can now be used in simulations to model the convection of the Earth's fluid outer core, giving us additional insight into the evolution of our magnetic field."

###

For more information, contact: Lauren Waszek Mobile: +44 (0) 7766881777 Email: lw313@cam.ac.uk

Dr Arwen Deuss Mobile: +44 (0)7913416063 Email: adf28@cam.ac.uk

Dr Jessica Irving Jcei2@cam.ac.uk

Notes to editors: The paper 'Reconciling the hemispherical structure of Earth's inner core with its super-rotation' is scheduled for advanced online publication in Nature Geoscience on Sunday 20 February.


TOPICS: Science
KEYWORDS: catastrophism; jmarvinherndon; magneticfield; magnetism; poleshift

1 posted on 02/21/2011 4:47:16 PM PST by decimon
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To: SunkenCiv

As the world turns ping.


2 posted on 02/21/2011 4:48:00 PM PST by decimon
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To: decimon

Scientific spin.


3 posted on 02/21/2011 4:48:53 PM PST by cripplecreek (Remember the River Raisin! (look it up))
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To: decimon

We’re doomed.


4 posted on 02/21/2011 4:49:38 PM PST by the invisib1e hand (Every knife in my back pushes me forward.)
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To: decimon

“,,,scientists from the University of Cambridge have discovered that earlier estimates of 1 degree every year were inaccurate and that the core is actually moving much slower than previously believed – approximately 1 degree every million years. “

LOL...how can scientists be so totally WRONG about so many “facts” that “everyone” accepts for years? Wonder how many taxpayer grants were wasted publishing dire warnings about the spinning core of the earth.


5 posted on 02/21/2011 4:54:13 PM PST by kittymyrib
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To: decimon

This explains my acid reflux...


6 posted on 02/21/2011 4:56:55 PM PST by OrangeHoof (Washington, we Texans want a divorce!)
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To: decimon

It’s obviously Bush’s fault. When he was President it sped up. Now that Obama is President, it’s slowed back down.


7 posted on 02/21/2011 4:56:54 PM PST by Brilliant
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To: decimon

Bush’s fault.


8 posted on 02/21/2011 4:57:12 PM PST by Colonel_Flagg ("It's hard to take the president seriously." - Jim DeMint)
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To: decimon

Arizona was -13 degrees give or take 20 years ago, where is it now


9 posted on 02/21/2011 4:58:29 PM PST by eyedigress ((Old storm chaser from the west)?)
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To: decimon

They can’t even get a simple global measurement like this right, but they know what global climate is doing, even though there are an infinite number of variables.


10 posted on 02/21/2011 5:19:34 PM PST by E. Pluribus Unum ("If they bring a knife to the fight, we bring a gun." -- Barry Soetoro, June 11, 2008)
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To: decimon
> ...time for the differences to freeze into the structure...

Isn't "freeze" kind of the wrong word here? Aren't the temperatures extremely high? What's wrong with "solidify"?

I'm in a mood to pick nits tonight... watch out! :)

11 posted on 02/21/2011 5:31:00 PM PST by dayglored (Listen, strange women lying in ponds distributing swords is no basis for a system of government!)
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To: decimon

” an east-west hemispherical difference in velocity is frozen into the structure of the inner core.”

Read it three times and still don’t comprehend how two halves of a sphere can move at different velocities. Guess I’m not as smart as I used to be.


12 posted on 02/21/2011 5:44:25 PM PST by mrsmith
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To: dayglored
"feeze", "melt" ~ these terms refer to phase changes.

They are not to be confused with such terms as frozen, melted, solid, liquid, gaseous, plasma or douflopped

13 posted on 02/21/2011 5:49:31 PM PST by muawiyah
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To: decimon
Perhaps the paradigm here is, of all people, Mrs. Cunningham from "Happy Days", when in one episode, she specifically told the "Fonz" to "sit on it and rotate".

Left to my own devices, I rather doubt that my comment on this would be as temperate.

FReegards!

14 posted on 02/21/2011 5:57:52 PM PST by SAJ (Zerobama -- a phony and a prick, therefore a dildo)
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To: decimon; 75thOVI; aimhigh; Alice in Wonderland; AndrewC; aragorn; aristotleman; Avoiding_Sulla; ...

Thanks decimon. Pole shift-related.
 
Catastrophism
 
· join · view topics · view or post blog · bookmark · post new topic · subscribe ·
 

15 posted on 02/21/2011 6:19:27 PM PST by SunkenCiv (The 2nd Amendment follows right behind the 1st because some people are hard of hearing.)
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To: muawiyah
They are not to be confused with such terms as frozen, melted, solid, liquid, gaseous, plasma or douflopped

douflopped? Is that anything like doo-wap?

16 posted on 02/21/2011 6:22:47 PM PST by 6SJ7 (atlasShruggedInd = TRUE)
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To: 6SJ7

Kinda, sorta ~ yeah, something!


17 posted on 02/21/2011 6:23:45 PM PST by muawiyah
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To: 6SJ7

Did you realize that when it comes to the relative rates of rotation of the inner and the outer core there’s not a doggoned thing any of us can do about it.


18 posted on 02/21/2011 6:25:18 PM PST by muawiyah
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To: 6SJ7

Makes me feel so helpless ~ utterly and totally helpless.


19 posted on 02/21/2011 6:26:00 PM PST by muawiyah
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To: SunkenCiv
Pole shift-related.

Only in Cleveland. Everywhere else they get regular jobs now.

20 posted on 02/21/2011 6:27:46 PM PST by decimon
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To: muawiyah
"Did you realize that when it comes to the relative rates of rotation of the inner and the outer core there’s not a doggoned thing any of us can do about it."

Chuck Norris could reverse the direction of the earth's rotation with a single roundhouse kick if he wanted to.

Good thing he doesn't want to.

21 posted on 02/21/2011 6:29:22 PM PST by Joe 6-pack (Que me amat, amet et canem meum)
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To: decimon

Kinda getting sick of these Guesstimates by scientists passed of as fact......


22 posted on 02/21/2011 6:34:54 PM PST by jakerobins
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To: decimon

From one degree a year to one degree a million years. Not much difference there.


23 posted on 02/21/2011 6:37:59 PM PST by Let's Roll (Save the world's best healthcare - REPEAL, DEFUND Obamacare!)
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To: SunkenCiv
Oh, so they changed it from 1 per year to 1 per million years? That's such a minor mistake lol.
24 posted on 02/21/2011 6:49:34 PM PST by rdl6989 (January 20, 2013- The end of an error)
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To: decimon
earlier estimates of 1 degree every year were inaccurate and that the core is actually moving much slower than previously believed – approximately 1 degree every million years.

I suspect that these are the same guys who figured out that whole global warming thing. In fact, I register the domain www.glabalcoreslowdown.com. It may become the next cataclysm-du-jure...

25 posted on 02/21/2011 6:56:05 PM PST by Onelifetogive (I tweet, too...)
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To: decimon

:’)


26 posted on 02/21/2011 6:59:31 PM PST by SunkenCiv (The 2nd Amendment follows right behind the 1st because some people are hard of hearing.)
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To: decimon
However, scientists from the University of Cambridge have discovered that earlier estimates of 1 degree every year were inaccurate and that the core is actually moving much slower than previously believed – approximately 1 degree every million years.


27 posted on 02/22/2011 6:41:25 AM PST by Oztrich Boy (I disagree with what you say but will defend to the death your right to say it -Voltaire)
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To: decimon

Per the foot note 17:

“It was also noted that the concentration of liberals in San Francisco and Berkley along with those in Cambridge produce the phenomenon called Crustal Drag.”


28 posted on 02/22/2011 7:05:27 AM PST by bert (K.E. N.P. N.C. D.E. +12 ....( History is a process, not an event ))
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To: rdl6989

“One — little — mistake.” — Cap’t Kirk


29 posted on 02/22/2011 3:47:05 PM PST by SunkenCiv (The 2nd Amendment follows right behind the 1st because some people are hard of hearing.)
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To: Joya

Of possible interest.


30 posted on 03/02/2011 7:23:38 PM PST by SunkenCiv (The 2nd Amendment follows right behind the 1st because some people are hard of hearing.)
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