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I tweeted Jim Cantore a Certified Broadcast Meteorologist and AMS (American Mathematical Society) Fellow who is currently working for the Weather Channel asking about a show that he did with his meteorologist associates on the aspect of Niagara Falls.
The show was demonstrating that although the Falls had indeed frozen it was still running underneath. I asked if it were possible for The Falls to be the beginning average for a glacier. The balance of such is for the Weather Channel and their reports in such concerns however I began to think about the real question which was more in depth and to the caliber of what I had been told as a child. I was told that Earth would wobble.
As I stared at whom said it I wondered how such a wobble would attain grip on such an enormous mass bringing the ocean into what I had thought bringing the thought to global warming. The updated question for The Weather Channel would involve “How much does a glacier weigh” and should the melting of such a mass and the freezing of another mass such as Niagara create the weight distribution to change the equator a what would have described as”The wobble”?
In such an issue how would we be able to calculate such a move other that the consistency of the water flush? And, should we study this “Mass” now as both frozen, freezing and melting would we be able to gauge the actual movement and not suffer the query of “the flush”?
This query to what is that “Wobble” still lingers as it was said with great fear and enormous wonder making this delivery of such a relief as at the very least now there is a somewhat explanation on how such an enormous movement of Earth may be measured and not left to that question of more than a natural event.
"Earth does not always spin on an axis running through its poles. Instead, it wobbles irregularly over time, drifting toward North America throughout most of the 20th Century (green arrow). That direction has changed drastically due to changes in water mass on Earth.”
NASA Study Solves Two Mysteries About Wobbling Earth
Chandler wobble
The Chandler wobble or Chandler variation of latitude is a small deviation in the Earth's axis of rotation relative to the solid earth,[1] which was discovered by and named after American astronomer Seth Carlo Chandler in 1891. It amounts to change of about 9 metres (30 ft) in the point at which the axis intersects the Earth's surface and has a period of 433 days.[2][3] This wobble, which is an astronomical nutation, combines with another wobble with a period of one year, so that the total polar motion varies with a period of about 7 years.
The Chandler wobble is an example of the kind of motion that can occur for a freely rotating object that is not a sphere; this is called a free nutation. Somewhat confusingly, the direction of the Earth's rotation axis relative to the stars also varies with different periods, and these motions—caused by the tidal forces of the Moon and Sun—are also called nutations, except for the slowest, which are precessions of the equinoxes.
Predictions[edit]
The existence of Earth's free nutation was predicted by Isaac Newton in Corollaries 20 to 22 of Proposition 66, Book 1 of the Philosophiæ Naturalis Principia Mathematica, and by Leonhard Euler in 1765 as part of his studies of the dynamics of rotating bodies. Based on the known ellipticity of the Earth, Euler predicted that it would have a period of 305 days. Several astronomers searched for motions with this period, but none was found. Chandler's contribution was to look for motions at any possible period; once the Chandler wobble was observed, the difference between its period and the one predicted by Euler was explained by Simon Newcomb as being caused by the non-rigidity of the Earth. The full explanation for the period also involves the fluid nature of the Earth's core and oceans—the wobble, in fact, produces a very small ocean tide with an amplitude of approximately 6 mm (1⁄4 in), called a pole tide, which is the only tide not caused by an extraterrestrial body. Despite the small amplitude, the gravitational effect of the pole tide is easily detected by the superconducting gravimeter.[4]
Measurement[edit]
The International Latitude Observatories were established in 1899 to measure the wobble as observed in latitude determinations. These provided data on the Chandler and annual wobble for most of the 20th century, though they were eventually superseded by other methods of measurement. Monitoring of the polar motion is now done by the International Earth Rotation Service (IERS).
The wobble's amplitude has varied since its discovery, reaching its largest size in 1910 and fluctuating noticeably from one decade to another. In 2009, Malkin & Miller's analysis of IERS Pole coordinates time series data from January 1946 to January 2009 showed three phase reversals of the wobble, in 1850, 1920, and 2005.[2]
Hypotheses[edit]
Since the Earth is not a rigid body, the Chandler wobble should die down with a time constant of about 68 years,[5] a very short period compared to geological timescales. The processes that continually re-excite the wobble are of interest to geophysicists. While it must be due to changes in the mass distribution or angular momentum of the Earth's outer core, atmosphere, oceans, or crust (from earthquakes), for a long time the actual source was unclear, since no available motions seemed to be coherent with what was driving the wobble.
An investigation was done in 2001 by Richard Gross at the Jet Propulsion Laboratory managed by the California Institute of Technology. He used angular momentum models of the atmosphere and the oceans in computer simulations to show that from 1985 to 1996, the Chandler wobble was excited by a combination of atmospheric and oceanic processes, with the dominant excitation mechanism being ocean‐bottom pressure fluctuations. Gross found that two-thirds of the "wobble" was caused by fluctuating pressure on the seabed, which, in turn, is caused by changes in the circulation of the oceans caused by variations in temperature, salinity, and wind. The remaining third is due to atmospheric pressure fluctuations.[5]
Chandler wobble of Mars[edit]
Using radio tracking observations of the Mars Odyssey, Mars Reconnaissance Orbiter and the Mars Global Surveyor spacecraft, the Chandler wobble of Mars has been detected. It is the first time it has been detected on a planetary body other than the Earth. The amplitude is 10 cm, the period is 206.9 ± 0.5 days and it is in a nearly circular counterclockwise direction as viewed from the North Pole.[6]
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