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Posted on 02/23/2013 1:31:31 PM PST by SunkenCiv
New analysis shows that the Chandler Wobble in Earth’s axis changed phase by 180 degrees in 2005. The question is why.
If you travel to the Arctic and attempt to find the axis of Earth’s rotation, you’ll notice something odd. The position of this axis on Earth’s surface moves with a period of about seven years. This is the combined result of two effects. The one we’re interested today is called the Chandler Wobble, which has a period of 433 days and was discovered by American astronomer Seth Carlo Chandler in 1891.
The Chandler Wobble is reasonably well understood. Any spinning sphere that it is not entirely spherical should wobble in this way. However, on Earth, the wobble varies in amplitude from decade to decade, a motion that is thought to be the result of the changes in pressure at the bottom of the oceans caused by fluctuations in salinity, temperature, and ocean circulation.
But there is also something mysterious about the Chandler Wobble. In 1920, it underwent a sudden phase change of 180 degrees. Nobody knows why.
Now a new analysis of data on Earth’s rotation going back 160 years indicates that this event was not unique. Zinovy Malkin and Natalia Miller at the Russian Academy of Sciences Central Astronomical Observatory in Pulkovo say the phase has changed by small amounts on many occasions during this time. But the big news is that the wobble underwent 180-degree changes in phase on two other occasions: once in 1850 and the other in 2005.
So why should the Chandler Wobble undergo these changes in phase? An interesting puzzle for anybody with a few brain cycles to spare.
(Excerpt) Read more at technologyreview.com ...
http://arxiv.org/abs/0908.3732
Chandler wobble: two more large phase jumps revealed
Zinovy Malkin, Natalia Miller
(Submitted on 26 Aug 2009)
Investigations of the anomalies in the Earth rotation, in particular, the polar motion components, play an important role in our understanding of the processes that drive changes in the Earth’s surface, interior, atmosphere, and ocean. This paper is primarily aimed at investigation of the Chandler wobble (CW) at the whole available 163-year interval to search for the major CW amplitude and phase variations. First, the CW signal was extracted from the IERS (International Earth Rotation and Reference Systems Service) Pole coordinates time series using two digital filters: the singular spectrum analysis and Fourier transform. The CW amplitude and phase variations were examined by means of the wavelet transform and Hilbert transform. Results of our analysis have shown that, besides the well-known CW phase jump in the 1920s, two other large phase jumps have been found in the 1850s and 2000s. As in the 1920s, these phase jumps occurred contemporarily with a sharp decrease in the CW amplitude.
Journal reference: Earth Planets Space, 2010, v. 62, No. 12, 943-947
What is Chandler Wobble caused by and how well can it be predicted?
Ask the Space Scientist
Dr. Sten Odenwald (Raytheon STX)
http://image.gsfc.nasa.gov/poetry/ask/a11435.html
This is the name given to the movement of the earth’s pole by 0.7 arcseconds over a period of about 14 months. For more information, visit a site over at the National Radio Astronomy Obserrvatory and check out the IEPS Bulletin at the U.S. Naval Observatory which predicts the earth polar wander based on a mathematical model. Chandler Wobble is a periodic phenomenon which means that it can be modeled by ‘simply’ fitting a harmonic series of sines or cosines to the past record of deflections, and then using this empirical model to make limited forecasts into the future. From what I understand of the technical literature, the cause of this wobble is believed to reside in the natural resonances in the body of the spinning earth due to the detailed distribution of mass in its surface, interior, oceans and atmosphere. This system has a ‘14-month’ harmonic which can be excited through a complex pattern of forcings by the moon, sun and sudden crustal rearrangements (earthquakes). There are many distinct periodic excitations by the sun and moon and their changing distances and tidal forcings, and these result in distinct monthly, yearly and multi-year periodicities in the polar wander. The Chandler Wobble may be a natural harmonic resonance that is also stimulated by these other constant lunar-solar forcings at the natural resonance frequency of the solid earth.
Bingo!!! Five for five!
Bush’s fault.
Jake: No, I didn’t. Honest... I ran out of gas. I... I had a flat tire. I didn’t have enough money for cab fare. My tux didn’t come back from the cleaners. An old friend came in from out of town. Someone stole my car. There was an earthquake. A terrible flood. Locusts! IT WASN’T MY FAULT, I SWEAR TO GOD!
Off the top of my head, the Boxing Day earthquake of 2004 caused it.
“This is Chandler Bing.”
“Wow, short message.”
This will no doubt be linked to human-caused global climate disruption. Just wait.
"Er, what? Spinning?"
That was what I was thinking. It should be interesting to see if there is any change after the Japan earthquake and tsunami.
Ask that reporterette who wondered on air whether that asteroid's trajectory might have been altered by global warming.
THE EARTH IS BECOMING UNINHABITABLE!!!!!
ALL HANDS ABANDON SHIP!!!
Does this mean my Celestron needs to be re-programmed?
2005 is clearly Bush’s fault. 1920 is presumably his grandfather’s fault. 1850 is probably the fault of his great-great-great-grandfather James Smith Bush.
Speaking of poles, without one to grasp onto, it’s no wonder she’s wobbling back & forth…
:’) Probably updates via the www?
Oh, it’s been done. :’) Check out the links.
This will have terrible implications for women and minorities.
I left a long time ago.
Maybe Nancy Leider is right about the polar shift? ;)
Nah. Those apartment buildings are where they've always been...you, on the other hand...(teehee)
i can make her go either way... which way is she supposed to be spinning???
I wanted to post a picture of Chandler Bing! LOL. :)
It is a left brain, right brain exercise. To see her spinning both ways means you are switching between your right brain and left brain.
“Caused by (global warming climate change) rising expectations... “
__________________________________________________
The changes to the Chandler (Bing) wobble were completely unexpected by scientists! LOL!
So the Congressman who claimed the island of Guam was becoming top heavy and might tip over was on to something.
i see her initially as turning to the right/clockwise, so am i right brain dominant???
No, but your Interocitor may be a little de-tuned for a bit
That could easily account for the creation of the pressure on the ocean bottom that drives the wobble.
With only a couple of major data points we don't know if this is related to anything in particular ~ I do believe this measurement is near the limits of quantum noise.
You are left-handed?
That was back when I had more hair.
Wonder if the 2004 Christmas 9.2 quake along with the Easter 2005 8.x quake had something to do with this? I know the former speeded up the Earth’s rotation by a few microseconds.
It spins left for me unless I change it. I am left handed. which means I am (for the moment) in my right mind. Lefties of the world UNITE! Left is right!
And did you know? Everyone is born right-handed.
Only the greatest can overcome it.
Interestingly, if I do something like typing, and “think” about what I am typing, while sorta half looking at the girl she swings her leg back and forth. So now I’m a wondering if I can get her to STOP.
That was back when I had more hair.
Clockwise
no...
yeah, i've seen her stutter back and forth also
You are all right after all.
•Earth Is Undergoing True Polar Wander, Scientists Say
•Scafetta’s new paper attempts to link climate cycles to planetary motion ( March 2012)
•Wind can keep mountains from growing
•Magnetic Polar Shifts Causing Massive Global Superstorms
•Magnetic polar shifts causing massive global superstorms
•Cosmic Impact Site That Created Earth’s Axial Tilt and Fault Lines
•Sun, moon trigger San Andreas tremors: study
•North By Northwest
•Geophysicist Discovers Why Earth ‘Wobbles’ [ 2004 ]
•In Climate Controversy, Industry Cedes Ground
•The ‘wobble’ that wipes out life on Earth every 2.5m years
•Global Warming Needs New Look at Mechanisms Involved
•Rhythmic Submarine Volcanos And El Niños
•Chandler’s Wobble Causes Earthquakes, Volcanism, El Nino, and Global Warming
For true links, go to SunkenCiv
Cthulhu stirring uneasily in his sleep in R'lyeh.
What a great Art Bell show this would’ve been. Fascinating subject.
Have you ever done a polar alignment to better than 0.7 arcseconds? That’s about the diffraction limit of a 10” telescope.
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