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Earth's Wobble Introduction | Table of Graphs & Charts | Key Findings
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Background Information & Knowledge/Data Sources:
Spin Energy In The Earth's Mass
John Carnicom provides an interesting computation of the spin energy in the mass
of the Earth: 1E+29 Joules lost one second of time per day: 5.943E+24 Joules one second per year: 1.6E+22 Joules one second per 45 day period: 1.3E+23 Joules Carnicom succinctly observes that "This exists as a tremendous amount of energy in a transformational state." For details, see http://www.carnicom.com/time3.htm
Energy Occurrences In Phenomenon http://www.phy.syr.edu/courses/modules/ENERGY/ENERGY_POLICY/tables.html
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The Drift, Anomalies, & Correlations Abstract A. IERS Graphs The Storyboard begins with five graphs which are posted at the iers.org website (International Earth Rotation Service). The Storyboard for these graphs provide the basic orientation to the concepts of polar motion and the wobble and an understanding of all the terms.
B. X & Y Plots of Wobble Motion
C. Wobble Track Plots
D. Solar Activity Correlation Graphs
G. True Polar Wander Graphs (drift of average location of the Spin Axis)
Just how do you calculate the true pole of the Spin Axis and its rate drift as it slowly changes location through the decades? Here are four methods.
The first is the method used by IERS geophysicists. It is a statistical average. Essentially, it is a mathematical fantasy of an "approximate" true location of the Spin Axis and its progressive drift. It is not such a bad one, but it leaves a lot to be desired. It essentially cuts us off what is really happening in the wobble and makes us oblvious to its connection to other factors.
The second method the author devised to look at the progressive march of each wobble spiral and cycle taken in its largest wobble. When the Wobble is at its MAX phase of spiral size, the track is the most perfectly circular and regular. A statistical "average" computed on this circle might have the least deviance factors but all the variations in the drift of the wobble from MAX to MAX could be defined. It is an interesting approach and in fact it demonstrates without doubt that "averages" hide a lot of phenomenon. But this approach suffers greatly from the fact that the wobble cycle is somewhat unstable and can be highly variable. The approach flamed out on the chaos which seems to rule. The drift of the wobble, and its variable rate, can both be clearly be seen, but between (1) and (2) we have apples and oranges. What to do?. Also what to do about the changing size of the wobble.
The third method the author devised under the simple theorem that the wobble must be the most stable during the MIN phase. The Earth is wobbling the least at this time, hence must be closest to its point of real mass balance, the real "mass" pole of the Spin Axis, minus all external complications which shift the balance. Not a bad observation. In fact a plot of the X MIN locations (averages computed during the smallest spiral tracks) is far superior to the first two. The track is clearly linear with some episodic hunting episodes, the rate is variable, defining and proving what the XY plots and circular charts clearly reveal (the shift in the overall seven year wobble spirals sometimes vary from cycle to cycle), and, best of all worlds, the average rate of drift computed from this approach agrees closely with the average of the annually averaged locations. Accordingly, then, these appear to be useful numbers.
For the overall drift, even better is the fourth method. It is based on a profoundly simple but apparantly un-noticed or at least un-remarked upon fact. The track of the Wobble occassionally can be seen to exhibit "cartoid moments", which is a mathematical term to describe when an inward moving spiral line terminates and a new spiral line spontaneously generates to expand outward in what can be seen as the opposite direction. The cartoid moment in the spiral form is essentially the point when the yin turns into yang. The clearest expression of this is the cartoid which appeared in the Perihelion moment of 2006. Essentially the wobble ceased and the Spin Axis hung in one location for nearly two months, a remarkable, never before duplicated moment. Clearly a point which marks one cycle from another. Minute examination of the Xplot, season by season, month by month, of the wobble since 1890, identified a few other clear cartoid moments. In general the majority of MIN phases do not show a distinguishable cartoid, or at least not one this author was willing to work with, but mathematicians may be able to define many more moments than I have. This chart plots the easily defined cartoids, the first one in 1907, the last in early 2006. From these matrix definitions, the drift of the wobble can be easily plotted, the distances computed into centimeters, and the average plotted. Only six points were used, but they draw a line which in a stunning "coincidence" confirms Hofpner's average annual drift of the wobble and pretty much his general angle of the drift ..... The weakness of this approach is that you cannot define variations in the rate of drift from wobble cycle to wobble cycle, only in ad=hoc groups of them, and you lose you ability to see the "hunting episodes" which appear in the other tracks. The fact that these six cartoid moments define a century's worth of average drift in the "statistical average location of the Spin Axis suggests clearly that these cartoid moments do in fact represent the true location of the Spin Aix when its mass is in true spin balance.
H. Correlations With Earthquakes
I. Correlations With Volcanism
J. Correlations With Global Warming
K. Graphs Which Display The "Bad IERS Series" Introduction All the wobble and polar motion charts were constructed
from a rather hefty Excel spreadsheet which contains the IERS
database of polar motion since 1846. This spreadsheet, created by MW
Mandeville, is entitled
"WobblePlots_1846-now.xls". All the charts are "native"
within the spreadsheet. It will be available during
2007 for download through a
subscription to the Earth Changes Bulletin or Phoenix Quest website
or on a CDROM. If you wish to use this file and cannot locate
a link for it, use email to inquire about the availability of this file. Many of these charts were originally composed in the period 1999-2001 and some of them have lived on the Iway since then. All of these earlier graphs should be eliminated and replaced by these updated versions. This replacement is required by changes in the underlying databases. Many corrections, additions, and updates have been made in many of the online databases, most especially in the Earthquake Catalogs and in the IERS database of polar positions for any given date. Though the differences are mostly quite subtle and only rarely can be detected in the graphs, it is a good idea to eliminate the obsolete versions. It is extremely embarrassing being observed using obsolete, incorrect information. One cautionary note on the IERS data which underlies all of the polar motion charts. The graphs on based on data series which were updated during the period 2001-2005. These graphs, however, DO NOT reflect changes made in the historical database during 2006/2007 by the IERS network. When Mandeville activated updates for the charts to incorporate the revised data series after 2006, certain ragged anomalies appeared in the charts. Examination of the anomalies appear to suggest that they are "mathematical artifacts", not real anomalies in polar motion. Accordingly, Mandeville is convinced that the last round of "adjustments" (as of January 15, 2007) have resulted in a database which contains relatively small but occassional strange errors, principally in the first half of Century 20. Accordingly, the numbers used for all polar positions prior to 2005 are based on numbers downloaded prior to 2005. All numbers for dates since 2005 reflect the IERS database as of January 2007. Charts which reveal the anomalies in the "bad series" may be found in the Table of Graphs, below.
Key Observations & Findings About How The Drifting Of The Wobble Causes Changes In The Earth The standard take on polar motion, polar drift, and Earth's Wobble in the reference books is one dimensional and needs consciousness expansion. The standard take is essentially based on statistical averages manipulated by mathematicians who are seeking to locate the exact location of the wobble at any moment in time. They are now every good at this. But the use of annual average positions of the Spin Axis (the center of the Wobble) creates "a statistical fiction" and abstruse mathematical ways of talking about the wobble which do not do anyone else much good. Important changes and dynamics in the Wobble and the geophysics of the Earth are hidden by this fiction and the obscure ways in which it is presented.. Among the hidden dynamics are profoundly important variations in the 7 Year Wobble Cycles. For instance, when 100 year averages are abandoned and plots of polar motion are made to study the actual shifts in the Wobble Cycles through the 18 historical wobble cycles which are easy to define since 1890, it is easy to observe substantial variations in the rate of drift, in the direction of drift, as well as "hunting" incidences which reveal mass imbalance in the spinning globe, and other anomalies. These are primary "facts" about the dynamics of the Earth which are more or less ignored, except in this Storyboard. Here are a few of the most important observations about the Wobble which can be made from the graphs in this Storyboard. The average rate of drift in the "average" absolute location of the Spin Axis (which is equivalent to the average center of the Wobble) has been measured to be 12.6 centimeters per year since 1900 along Longitude West 80 by Hofstader. See Chart xxx. This average measurement "hides" the fundamental possibility that this drift in the location of the Wobble may be only about 90 years old. Examination of the charts of polar motion clearly demonstrates that no drift in the wobble of the Spin Axis (True Polar Wander) was apparent from 1846 until nearly 1916. No matter how you plot the location numbers, or compute them, drift prior to 1916 bobbed and meandered with a net change of nearly "0". Since then drift of the Wobble has gone through several phases (or perhaps better described as short-lived eras) during which the average rate of drift varied significantly. The rate of drift may have accelerated to as high as xxx, though more typically it fell in the range of xxxx to xxx. Some of this acceleration paralleled a substantial acceleration of tectonic change. Thus it would appear that the average measurement "hides" short eras of acceleration and change in the drift which may have directly produced significant tectonic activity. During the period of about 1925 to 1945, the bobbing meander in the average location of the wobble during the prior century began to become far more directional, i.e., change along a definite Longitude. This varied significantly and caused various researchers to report directions which varied from about Long. West 60 to about West 90. The directionality has increasingly tended to become more and more parallel with Longitude West 90, and this can be seen most esp. since....xxx. Hofstader's century average of Longitude West 80 is a good one, but this average may be hiding a strong tendency during the past 50 years to shift down Longitude West 90. For those with orbital and plasma minds, this is a highly significant fact. This shift is very closely tracking with the Longitude of the Magnetic North Pole (on Longitude West ~114, Latitude North ~83). During the past 80 years, for unknown reasons, the Magnetic North Pole has begun accelerating its rate of drift (now 40 km per year) towards the North Spin Axis on the same side of the Earth, indeed within the same quadrant of the Earth. Given the physics of motion and balance on so vast a scale, it is unlikely that these behaviors are unrelated. Something connects them, the question of course is, what? In the era 1925-1945, In the era 1935-1955 In the era 1955 ---- Since approx. 1990, the rate of drift has slowed... The Solar Connections The El Nino Connection The Divergence & The Tectonic Trends Global Warming To make these analyses, it is highly convenient to identify each of the 7 Year Wobble Cycles with a specific number. This makes for easier communication of comparisons between the wobble cycles (which vary a lot). It also helps in discussion of correlations with other phenomenon. The easiest method for numbering the Wobble Cycles is to identify and number the largest spiral wobble tracks. These re-occur nearly every seven years and are easily distinquished. Since 1890, 18 Wobble cycles can be counted. Prior to 1890, the data is too sparse to graph out the Wobble in a way which is smooth enough to consistently distinguish the largest spirals, thus these are not numbered and the series starts in 1890. Sophisticated filtering and re-projection mathematics would be required to define these Wobble Cycles but it hard to determine if this would be worth the trouble.. The Wobble happens to have been in its MAX phase during 1890, which thus becomes Wobble Cycle #1. Currently we are shifting into Wobble Cycle #19. We are currently in the first of six spiral tracks which will define Wobble Cycle #19.
Old Stuff The Drift & Anomalies of Earth's Shifting Wobble from 1846 to 2007
In this multi-dimensional, multi-perspective view of the historical track of the Spin Axis, some three dozen graphs and charts demonstrate that Chandler's Wobble is progressively shifting the location of the spin axis and the shape of the earth to produce increased tectonic activity, El Nino, and Global Warming at an accelerating rate since 1916.
Introduction To The Earth’s Wobble:
The physical Earth is in constant motion relative to its orbital Spin Axis. This gives rise to many consequences which are not yet understood even by scientists. These consequences range from continental drift, volcanism, and ceaseless earthquakes, to global climate cycles ranging from El Nino to long term shifts which can range from a few hundred to tens of thousands of years in duration.
This motion of the Earth is usually described as the motion of the pole or spin axis. Most of this motion is a slight wobbling motion in the Earth’s spin. This wobble, which is similar to the wobble one can see on a child’s top which is slightly off-center, is named the Chandler Wobble (or Chandler’s Wobble) after the name of the 19th century scientist who first “discovered” it. As the Earth spins each day, the focal point of the spin (the focal point is the pole or Spin Axis) creeps slowly around in a circle It takes about 14 months for the Spin Axis to creep back to the same longitude on the circle.
The story gets more complex than this because the radius of the creep varies on a seven year cycle. For approximately three and a half years, the circle slowly expands to a radius of about 50 feet, after which it slowly contracts to a radius of about 20 feet. To make the story even more complex, the amount of expansion and contraction also varies from cycle to cycle, usually by a small amount but occasionally by a relatively large percentage. This makes each seven year wobble cycle virtually unique. Studies have been made of these variations and a few scientists think that some long term cycles are present in these variations of the motions of the pole. Unfortunately, however, human world databases are not yet long enough on the time line to be able to be certain of very much about any long range cycles.
There is another layer to the complexity of polar motion and this layer is the most important for understanding both the geological and climate changes of the Earth. The focal point of the wobble, day by day, year by year, is ceaselessly shifting or drifting to a new location. A few scientists have used a variety of means to define, measure, and analyze this drift. . Known as True Polar Wander, the current rate of drift (average for Century 20) has been defined by xxxx xxxx as xxxx. down approximately Long. W. 90. Other calculations of the drift have been made by other scientists and their results are similar to xxxx..
It is convenient for geophysicists to discuss the Earth’s wobble as motion in the poles or spin axis relative to a fixed grid (Longitude and Latitude) on the crust of the Earth. But this way of talking creates an illusion, one which is similar to saying that the Sun rises in the morning. The Sun of course does no rising, it is the Earth’s rotation which creates the illusion of the Sun rising. Similarly, the Spin Axis moves scarcely at all, almost all of the motion and drift of the Spin Axis is an illusion created by the movement of the physical Earth.
A better way to state the fundamentals of motion is that the Earth’s crust is in constant slow motion as it wobbles around a focal point of spin. The Earth’s mass shifts its orientation relative to the Spin Axis constantly, on a daily basis even, through many daily, annual, and other cycles. Although these shifts seem to be small amounts, they have large effects on navigation and location finders, thus the exact location of the Spin Axis on the Earth’s crust is carefully calculated on a daily basis by an international consortium of geophysicists.
The focal point of spin, which we call the Spin Axis, moves almost not at all, maintaining a fixed orientation to the North Star, Polaris. It is said, of course, that the Spin Axis shifts its orientation to Polaris very slowly in a long 25,000 cycle. But we can ignore this long slow cycle which is called the Precession. It simply is not connected with the wobble cycles in the Earth’s daily rotation. Or, other wise stated, the amount of energy transference between the two frames of reference must be exceedingly smaller than our brain lobes care to worry about.
Measuring The Motion Of The Crust (so-called Polar Motion)
Take a quick scan of the graphs below in order to get an image of in mind of what this discussion is about Then return here to get the grounding you need to understand the numbers which underlie the graphs.
The location and motion of the poles has been measured since 1846. Unfortunately the Y coordinate of the North Pole was lost for a few years during the 1850’s. The X without the Y on a graph is pretty worthless, so it is not possible to provide a consistent view back to 1845. It is best to begin with 1861. This nominally gives us a database of some 145 years (circa 2007) about the wobble.
The earliest series (for 1845-1889) define the postion of the Norht pole at 10 times during the year, roughly at five week intervals. The second series is for the period 1890 through to 1962, which uses 20 points during the year to define the location of the pole. The third series is for the period 1962 onwards and it uses daily measurements, 365 per year to define the position of the pole.
Prior to 1890, only ten measurements were made per year. This is far too scanty a sampling for circular graphs. It also makes the XY plots of this period inconsistent with later periods, which are based on 20 measurements per year or daily measurements. With ten points, a circular plot of the wobble is impossible unless mathematical “fiction” is introduced to extrapolate many additional points to make a circular plot look like a circular plot. Since a lot can happen in a 30 day segment of the Earth’s Wobble, as will be seen in the graphs and charts which follow, extrapolation is not really a good idea if one is trying to correlate the wobble with other natural phenomenon. It is like driving blind into a snowstorm.
Though the data prior to 1890 is not very good, since then the measurements have gotten better and better. From 1890 to 1961, a sampling of 20 locations per year is in the data base and these are complete. They make reasonable tracks of the changing location of the Spin Axis except when there are rapid shifts and anomalies in the motions of the crust. During these times, and these show up several times, the track on the circular graphs becomes somewhat jerky and perplexing.
Since 1962, real daily measurements (not extrapolations) are available. The circular plots improve greatly in quality and usefulness, jerky lines become profoundly meaningful rather than just unknown noise over the signal. This database provides the means to minutely study how the motions of the crust correlate with other phenomenon of the Earth.
All of this information is available online through the International Earth Rotation Service (www.iers.org) which is headquartered in Belgium. Keep in mind that the historical databases, unless otherwise stated, have been statistically “smoothed”. This means that a running average, based on a certain number of preceding measurements and evolved equations, has been used to “filter” out daily fluctuations. This is generally a good idea and it does not appear to lose important information. The Spin Axis, or more correctly stated, the Earth, literally does a daily loop de loop, which can stretch out for a few days, within the 14 month spiraling track of the wobble. The daily loop de loop is noise generated by the Earth’s major storms and tidal surges, and certain other environmental conditions, all of which have minute effects on the exact mass balance of the Earth and its resulting angle of spin.
How are the measurements made? Bu using the timing and angles of the stars as they appear on the horizon or other parts of the sky in various parts of the Earth, scientists have been able to faithfully plot the orientation of the Earth as it wobbles slightly from year to year. By knowing exactly how the Earth is oriented towards certain stars and the Sun, Earth scientists can determine exactly where the true spin axis poles (North and South) are located. Earth scientists measure the orientation of the Earth and calculated the locations of the poles every day. The figures which they generate, which are known as the X and Y coordinates of the “geophysical pole”, are used to currect highly sensitive navigational equipment and scientific devices which record astrophysical information.
Necessaryly, the cicular plots for the first series is jerky
The second series is better, except when the motion of the pole becomes irregular, then the plots seem jerky but some of the jerkiness is exaggerated by the small number of defining oints. The extreme jerky irreguarily you see in the circular plots for the early years is thus highly exaggerated and the true motion of the pole was considerably smoother and more circular. This problem is elimiknated of course in the daily series from 1962 onwards.
Chart 500Polar Motion 1861-1962
Provides a composite of a century of polar motion. The total track of the pole is shown for the century, each color represents a 6.5 year spiral of the Min and Max in the motion of the crust in Chandler’s Wobble. except that the first thirty year period is shown in black The detail is so thick, many of the spirals seem so irregular, and the tracks are so overwritten by others that it is very difficult to understand the dyamics of motion.
Nonetheless, by comparing the 1958-1962 spiral (shown in white) with the 1861-1890 spiral shown in black, some movement of the 6.5 year colored spirals can be seen. Through a century of motion, it is fairly clear that the average location of the pole (which is the center or eye of each 6.5 year colored spiral) has shifted towards the left (towards the Great Lakes) and slightly down (towards England). Exactly how much is impossible to determine from this chart.
Chart 501Polar Motion 1861-1962
Provides a simplified, less confusing way of showing a century of polar motion. The total track of the pole is shown in four colors, each color represents a long era of time rather than 6.5 years, the first period is in white, the next period is in black, the third is in green, and the latest period in in red. If one looks into the center or eye of the red spiraling circles, one can see what is approximately the average position of the pole for xxxeidt years. Though obscured, one can fairly easily visualize the approximate center of the white spiral circles. From these two points one can estimate readily that the total drift of the average location of the pole seems to be in fairly straight line down towards the left hand side of the chart. The total distance is about .15 arcseconds, which is just slightly more than 15 feet or about 4.5 meters. Or, the yearly average is about 1.8 inches (very close to 3.06 centimeters dead on).
Chart 502Can we find out more about the dynamics of polar motion by examining the individual spirals in greater detail? As a matter of fact we can, we can make the most important discovery about Chandler’s Wobble since it was noticed that the Wobble is influenced by all of the mass variables of the earth, including the motions of the atmosphere (fluctuating with the weather) and the behavior of the ocean tides. We make this discovery by plotting each spiral in separately and slowly building up the composite to look for any changes in motion.
In Chart 502 we can see in Black the spiral plot of the location of the pole during 1903-1909. Drawn from 20 points per year, it appears far more circular and regular than the jerky appearing plots for the periods of 1861-1890. We can also see that the average location of the pole does not appear to have moved by much, if at all. It would take a mathematician with fancy formulaes to accurately define the infinitesmal drift and as we can see it is probably not worth it, partly because the data is too sparse.
Hold on to this factoid. We have 50 years of measured polar motion and, though great variation in the 6.5 years cycles of Chandler’s Wobble are quite obvious, there IS NO DISCERNIBLE DRIFT IN THE LOCAITON OF THE AVERAGE POSITION OF THE POLE. Chart 503Look what happens when we add in the 1909-1919 spiral. We can immediately sense some apparent drift in the eye of the wobble.
Chart 504
We see even more apparent drift when we add in the 1919-1923 spiral.
Chart 505 1903-1923
Dead reckon centers on the computer screen or on a print-out for the black spiral 1903-1909 and for the blue spiral (1916-1923), the distance between them is about .07 arcsceonds. If we assume the rate of drift is constant from 1909 through to 1923, the rate of motion is approximatley 6.1 inches per year ( almost 15.5 centimeters/year). Serious mathematics can no doubt refine this crude number into something more precise and doubtless the number will be in the same range of increase.
After 50 years of no discernible drift, now suddenly we have 6 inches per year for 14 years.
a blue spiral form is diminished in size
Chart 506 1903-1931Does the motion continue? When we add the wobble spiral for 1923-1931 into the composite to create Chart 506 we get another surprise or two. The wobble is unseasonably longer than the average 6.5-7 year X Wave spiral cycle of Chandler’s Wobble. And the wobble is even more crunched down in size and seems to trace a bowl of spagetti. And there is no apparent drift of the “eye” of the wobble. Annual drift seems to have disappeared again. Chart 507 1931-1939The bowl of spagetti begins to turn back into a spiral, even though the size remains very small (of the white spiral) The “eye” might be even drifting but it is not very certain. Chart 508 1939-1945
The red spiral motion for this period is still trancated but the “eye” of this spiral in the wobble definitely appears to have move in the same direction as the previous drift of the eye. By now the eye seems to have moved a total of about .06 arcseonds since 1923 (the dark blue spiral is nearly dead on the geographic north pole position of x=0,y=0
but now the orange spiral eye of is about y=.06, y=.02
Chart 509 1945-1958Suddenly in about 1945 the wobble spiral expands outward and and become becomes as large as it had previsouly been prior ot 1923. As shown by the yellow and light blue colors, this enlarged pattern holds through 1958. Since all parts of the spiral are now enlarged, even the “eye’, it is now more difficult to estimate the center of the “eye” by using one’s eyeball. There may be a continuation of a slight amount of drift.
Chart 510 1958—1962
new node analysis starts here, reesitmate the time lengths for previous
Between the eye of 1920 and the eye of 1935, there is ony about .01 arcsecond of movement, if that much.
or, 0.81 inches per year, or 1.24 centimeter/year
Suddenly, as the yellow plot shows, the motion of the pole has become quite jerky and the eye of this spiral seems to have shifted quite suddenly by a relatively large amount. Using simple screen measurement, the eye of the yellow plot has shifted approximately .14 arcseconds since the eye of the 1931-1939 spiral. Since the eyes were literally in 1935 and 1960 respectively, we have a 25 year shift of .14 arcseconds at a rate of 6.8 inches per year (17.29 centimeters).
Interestingly enough, Cayce predicted in the mid 1930’s that we would notice a gradual increase in the rate of tectonic change after 1958. Since most of the apparent motion between 1935 and 1960 seems to have occurred after 1955, we find once again a strong correlation in the Earth Sciences which validates Cayce’s earth changes predictions.
It gets even more interesting as we pursue the tracks of the Phoenix in the daily series from 1962 to 2001.
The Drift & Anomalies of Earth's Shifting Wobble from 1846 to 2007
In this multi-dimensional, multi-perspective view of the historical track of the Spin Axis, some three dozen graphs and charts demonstrate that Chandler's Wobble is progressively shifting the location of the spin axis and the shape of the earth to produce increased tectonic activity, El Nino, and Global Warming at an accelerating rate since 1916.
Introduction To The Earth’s Wobble:
The physical Earth is in constant motion relative to its orbital Spin Axis. This gives rise to many consequences which are not yet understood even by scientists. These consequences range from continental drift, volcanism, and ceaseless earthquakes, to global climate cycles ranging from El Nino to long term shifts which can range from a few hundred to tens of thousands of years in duration.
This motion of the Earth is usually described as the motion of the pole or spin axis. Most of this motion is a slight wobbling motion in the Earth’s spin. This wobble, which is similar to the wobble one can see on a child’s top which is slightly off-center, is named the Chandler Wobble (or Chandler’s Wobble) after the name of the 19th century scientist who first “discovered” it. As the Earth spins each day, the focal point of the spin (the focal point is the pole or Spin Axis) creeps slowly around in a circle It takes about 14 months for the Spin Axis to creep back to the same longitude on the circle.
The story gets more complex than this because the radius of the creep varies on a seven year cycle. For approximately three and a half years, the circle slowly expands to a radius of about 50 feet, after which it slowly contracts to a radius of about 20 feet. To make the story even more complex, the amount of expansion and contraction also varies from cycle to cycle, usually by a small amount but occasionally by a relatively large percentage. This makes each seven year wobble cycle virtually unique. Studies have been made of these variations and a few scientists think that some long term cycles are present in these variations of the motions of the pole. Unfortunately, however, human world databases are not yet long enough on the time line to be able to be certain of very much about any long range cycles.
There is another layer to the complexity of polar motion and this layer is the most important for understanding both the geological and climate changes of the Earth. The focal point of the wobble, day by day, year by year, is ceaselessly shifting or drifting to a new location. A few scientists have used a variety of means to define, measure, and analyze this drift. . Known as True Polar Wander, the current rate of drift (average for Century 20) has been defined by xxxx xxxx as xxxx. down approximately Long. W. 80. (towards the Great Lakes). Other calculations of the drift have been made by other scientists and their results are similar to xxxx..
It is convenient for geophysicists to discuss the Earth’s wobble as motion in the poles or spin axis relative to a fixed grid (Longitude and Latitude) on the crust of the Earth. But this way of talking creates an illusion, one which is similar to saying that the Sun rises in the morning. The Sun of course does no rising, it is the Earth’s rotation which creates the illusion of the Sun rising. Similarly, the Spin Axis moves scarcely at all, almost all of the motion and drift of the Spin Axis is an illusion created by the movement of the physical Earth.
A better way to state the fundamentals of motion is that the Earth’s crust is in constant slow motion as it wobbles around a focal point of spin. The Earth’s mass shifts its orientation relative to the Spin Axis constantly, on a daily basis even, through many daily, annual, and other cycles. Although these shifts seem to be small amounts, they have large effects on navigation and location finders, thus the exact location of the Spin Axis on the Earth’s crust is carefully calculated on a daily basis by an international consortium of geophysicists.
Some people believe that the entire Earth wobbles around and over the spin axis. But geophysical evidence which has accumulated during the past 20 years directly suggests that it is just the crust of the Earth which wobbles by floating over the hot liquid mantle of the Earth's deep interior. This is an immense important and powerful finding. If this is true, we can explain the basic motions of Earth’s tectonic plates as a product of Earth’s wobble. Based on this we can pretty much explain rifting and subduction phenomenon, as well as most of the morphology of the surface of the Earth, as a product of orbital mechanics.
The focal point of spin, which we call the Spin Axis, moves almost not at all, maintaining a fixed orientation to the North Star, Polaris. It is said, of course, that the Spin Axis shifts its orientation to Polaris very slowly in a long 25,000 cycle. But we can ignore this long slow cycle which is called the Precession. It simply is not connected with the wobble cycles in the Earth’s daily rotation. Or, other wise stated, the amount of energy transference between the two frames of reference must be exceedingly smaller than our brain lobes care to worry about.
Measuring The Motion Of The Crust (so-called Polar Motion)
Take a quick scan of the graphs below in order to get an image in mind of what this discussion is about Then return here to get the overview grounding you need to understand the numbers which underlie the graphs and why the graphs were constructed the way they are.
The location and motion of the poles has been measured since 1846. Unfortunately the Y coordinate of the North Pole was lost for a few years during the 1850’s. The X without the Y on a circular graph is pretty worthless, so it is not possible to provide a consistent view of the wobble back to 1845. It is best to begin with 1861. This nominally gives us a database of some 145 years (to 2007) about the wobble.
A further difficulty arises in trying to see the wobble. Prior to 1890 (for 1845-1889), only ten measurements were made per year, roughly at five week intervals. This is far too scanty a sampling for circular graphs and it does not make for smooth X or Y graphs either.. It also makes the X and Y plots of this period inconsistent with later periods, which are based on 20 measurements per year or daily measurements. With only ten points, a circular plot of the wobble is impossible unless mathematical “fiction” is introduced to extrapolate many additional points to make a circular plot look like a circular plot. Since a lot can happen in a 30 day segment of the Earth’s Wobble, as will be seen in the graphs and charts which follow, extrapolation is not really a good idea if one is trying to correlate the wobble with other natural phenomenon. It is like driving blind into a snowstorm.
Though the data prior to 1890 is not very good, since then the measurements have gotten better and better. From 1890 to 1961, a sampling of 20 locations per year is in the data base and these are complete. They make reasonable tracks of the changing location of the Spin Axis except when there are rapid shifts and anomalies in the motions of the crust. During these times, and these show up several times, the track on the circular graphs becomes somewhat jerky and perplexing.
Since 1962, real daily measurements (not extrapolations) are available. The circular plots improve greatly in quality and usefulness, jerky lines become profoundly meaningful rather than just unknown noise over the signal. This database provides the means to minutely study how the motions of the crust correlate with other phenomenon of the Earth.
All of this information is available online through the International Earth Rotation Service (www.iers.org) which is headquartered in Belgium. Keep in mind that the historical databases, unless otherwise stated, have been statistically “smoothed”. This means that a running average, based on a certain number of preceding measurements and evolved equations, has been used to “filter” out daily fluctuations. This is generally a good idea and it does not appear to lose important information. The Spin Axis, or more correctly stated, the Earth, literally does a daily loop de loop, which can stretch out for a few days, within the 14 month spiraling track of the wobble. The daily loop de loop is noise generated by the Earth’s major storms and tidal surges, and certain other environmental conditions, all of which have minute effects on the exact mass balance of the Earth and its resulting angle of spin.
How are the measurements made? By using the timing and angles of the stars as they appear on the horizon or other parts of the sky in various parts of the Earth, scientists have been able to faithfully plot the orientation of the Earth as it wobbles slightly from year to year. By knowing exactly how the Earth is oriented towards certain stars and the Sun, Earth scientists can determine exactly where the true spin axis poles (North and South) are located. Earth scientists measure the orientation of the Earth and calculated the locations of the poles every day. The figures which they generate, which are known as the X and Y coordinates of the “geophysical pole”, are used to currect highly sensitive navigational equipment and scientific devices which record astrophysical information. Full technical documentation on how this is done can be found at iers.org.
What Can Be Seen In The Story Board
Technical Details About The Numbers, Units, and Charts
Algebraic Signs: The IERS database and charts use a logic for algebraic signs which is the reverse of what is commonly used in mathematics and on spreadsheets. The Minus Numbers are on the top and to the right, the opposite of most other charts in common use. The charts displayed here use the IERS logic to keep the story consistent with other geophysicists. Units of Arcseconds: The charts are shown in arcseconds of degrees. They are labeled Longitude degrees in the charts, but technically it is probably more correct to use the term Latitude. The distinction is meaningless at the poles, but technically there is a mathematical difference which actually adds up at the equatorial zone to several miles. The term Latitude was not used in the charts to avoid introducing an additional term of reference. Many of the charts use a grid structure equal to 0.1 per line. A 0.1 arcsecond is equal to 3.087 meters or 10.127 feet. The tiny grid lines mark either .01 or .02 Arcsecond;
Necessaryly, the cicular plots for the first series is jerky
The second series is better, except when the motion of the pole becomes irregular, then the plots seem jerky but some of the jerkiness is exaggerated by the small number of defining oints. The extreme jerky irreguarily you see in the circular plots for the early years is thus highly exaggerated and the true motion of the pole was considerably smoother and more circular. This problem is elimiknated of course in the daily series from 1962 onwards.
X Plot of Earth Wobble 1846-2001 X Plot Earth Wobble 1861-2001
Summary Overview 1861 to 2001 - Chart 500 The chart shows the plot of the location of the North Pole (spin axis of the Earth, not the magnetic pole) as it wobbles in the 14 month circles and 6.5 year spirals knows as Chandler's Wobble. Each spiral cycle since 1890 is displayed in a unique color and of course most of the spirals tend to blot out each other. Consequently, not much can be seen about the early cycles. Even so, we can glean two facts from this chart: (1) Some of the earlier spirals seem somewhat jerky and non-symmetrical compared to the more regular spirals of the recent past. (2) There is a definite movement of Chandler's Wobble (and thus the average position of the spin axis) since 1861 to the left of the chart along the Y axis in the direction of the Great Lakes. For more information, we will have to look into the individual spirals. Take note that this chart shows the center of the red spiral (the latest Wobble cycle) on about the X = .3 as line. For this and all other Excel charts, the largest spiral circle in the 6.5 cycle is the X Max and the smallest circle in the 6.5 cycle is the X Min. Since the X Min points in the spiral are always the most unstable and show the greatest variations, the X Max was chosen to mark the beginning of each cycle. The motion of the Earth during the X Max is always the most "regular" and symmetrical. Accordingly, the X Max movement every 6.5 years should be most like the previous spiral motions during the X Max 6.5 years prior. If changes are occuring, they will be most clearly seen by comparing the outer edges (X Max) of the spirals. For the most part, each X Max is shown in a different color. As will be seen, it turns out that most of the drift of Chandler's Wobble (the permanent "shifting of the poles") tends to occur during the X Max period. The pole appears to shift by making the X Max motion longer and deeper, then it never returns enough to move around the same "eye" of the preceeding years. Literally, a new "eye" seems to be created in the space of a few months of the Earth's most extreme wobble motion. Naturally, like all things celestial, there is some variation in the 6.5 year cycle. It can last up to three to four months longer. The choice of the X value (the measurement of the location of the pole relative to Greenwich Meridian) is arbitrary, the Y value (location of the pole relative to Long. West 90) could have been used. But since all of the vortex tectonic correlations have been made with the motion of the location of the spin axis up and down the X or Greenwich Meridian, these circular plots were also defined by using the X Max point to mark the beginning and end of each spiral cycle. Overview 1861 to 1964 - Chart 501 Chart 501: Plot of Chandler’s Wobble from 1861-1964 Even if we wack off the past forty years of polar motion plots, very little additional information can be discerned. We still see a definite migration of the location of the pole betweeen 1861 and 1964 in the same basic pattern. Note that the center of the most recent spiral in this chart (1958-1964) appears to be on about the X = 0.15 line. That would seem to imply, very roughly, a drift in the location of something like 0.15 as in about 61 years (from 1958 to 2001), which is, very approximately, 0.002459 as/yr or about 3 inches/year or 7.6 cm/yr. Polar Tracks 1861 to 1916 - Chart 502 Chart 502: Plot of Chandler’s Wobble from 1861-1916 More information about the path of the pole can be seen by just examining the first 56 years of measurements, which finally became consistent enough to use in a database in 1861. (Sporadic measurements began in 1845). We can see what appears to be a lot of chaotic jerkiness in the 1861-1890 plot. These plots are based on using 10 polar positions per year, which simply is not enough to produce a reasonably smooth curve. The actual motion of the pole was not nearly as spastic as shown. The only thing which seems reasonably clear is that there is not much motion in any particular direction. The plot is enough of a "ball" to that no net drift can be readily seen. We can discern the facts more clearly after 1890. These spiral plots are based on records of 20 polar positions per year and become real tracks rather than spastic jerks. By comparing the1861-1890 period with the plots for 1890-1903 and 1903-1909 (in black and green) we can see that there is no or very little apparent movement in the pole. The spirals all overlap each other fairly tightly A slight sense of movement down to the left bottom corner seems possible. But if calipers and rulers are used to bisect these spirals to define the average circle and center, net motion during this period seems negligible. In the 1909-1916 plot we notice an expansion of the spiral, it is larger that the 1903-1916 spiral with perhaps a slight drift towards the left bottom corner of the graph The outer circle of 1903 parallels well the outer circle of 1909, so not much motion is apparent there. The eyes of the two spirals seem to be slightly apart. This may be motion of the average location of the pole but it may be an illusion caused by the irregularites. The only major change appears to be that the 1909 spiral expanded in size. Accordingly, It would appear that there is over the course of 56 years almost no change in the average location of the pole. This finding is a fundamental fact which directly supports the vortex tectonics theorem. Imperceptible drift may be the normal condtion of the spin axis through most of the ages. If so, we have fully accounted for the anomalous fourfold increase in tectonic plate motion, earthquakes, and volcanic activity during the last half of the 20th century. It is directly related to an increasing tempo of drift in the location of Chandler's Wobble which is apparant in the last half of the 20th century. This is virtually the final proof that the vortex rules. But wait, the evidence builds. Polar Tracks 1861 to 1923 - Chart 503 Chart 503: Plot of Chandler’s Wobble from 1861-1923 With the addition of the 1916-1923 spiral we see a decided change. Suddenly the spiral form is smaller than it was for at least the two prior ones. It significantly smaller and became more irregular. If there is a shift in locus, appears to be towards the bottom of the chart and slightly towards the right The locus or center of the spiral seems to have defnitely shifted towards the bottom left corner of the graph. This can be measured on the graph by using four bisects of each spiral from their outer edges to establish their centers. By this method, it is possible that there was .05 as drift between 1903 and 1916. However, these spirals are a litlte too irregular to put much stock on this number. One can also simply analyze the relative positions of their outer edges. By this means there is no apparent drift between the 1903 spiral and the 1909 spiral. But it is possible that there was a shift of .02 as in 13 years from the 1903 spiral to the 1916 spiral. Polar Tracks 1903 to 1931 - Chart 505 Chart 505: Plot of Chandler’s Wobble from 1903-1931 What a change we see when we add the 1923-1931 spiral! Now the movement begins during the 1923-1931 X Wave along with great instability in the track of the spiral. The spiral waveform has degenerated into a bowl of spagetti. If there is a shift in locus, the shift is towards the left bottom corner but the 1923 spiral seems too difficult to average out to determine a number for the drift. Notice that the locus or center appears to be almost exactly the same as the Geographic North Pole, x=0 and y=0. For argument, suppose then that the center of the wobble has shifted some 0.075 arc seconds in the space of some 15 years, from 1916 to 1931 Polar Tracks 1903 to 1939 - Chart 506 Chart 506: Plot of Chandler’s Wobble from 1903-1939 The 1931-1939 spiral is still very small and is still somewhat chaotic but less so than the 1923 spiral. There is more of a sense of drift in the locus towards the left bottom corner but it is too difficult to compute. We wil have to wait for more regular spirals. The X Min, during about 1935/36, shows the strange crazy 8 which created the phase shift in Chandler's Wobble reported by Yumi et al to the IERS conventions and journals. As a result the spiral "appears" longer than the 6.5 year average. This crazy eight and phase shift confirmed Edgar Cayce's clairvoyant prediction about the change in the equilibrium of the earth causing a change in the Earth's orientation (a micro pole shift) during 1936. As we can see in the tracks of the pole, it was coming on since about 1916 at the earliest. Accordingly, 1916 may mark the best date for the end of polar stability which reigned during previous centuries and the time of the onset of the accelerating shift in the poles which is still gathering speed a century later. Polar Tracks 1903 to 1945 - Chart 507 Chart 507: Plot of Chandler’s Wobble from 1903-1945 The 1939 spiral is still erratic but far less so than the 1923-1931 period. The spiral seems to expand slightly and stabilize. Ddespite stabilization, the locus is still very difficult to determine. But it does allows us to see that the sense of slow drift which we have gathered since the 1916 spiral is becoming more definite. Notice that the entire spiral remains tight, very small like the 1916-1921 spiral. It seems obvious that the spiral has shifted at an accelerated rate. Since 1931 (at about 0,0 coordinates) the locus has probably shifted some .075 as. Polar Tracks 1903 to 1958 - Chart 508 Chart 508 Plot of Chandler’s Wobble from 1903-1958 Another radical shift! The 1945-1952 spiral suddenly expands radically to make Chandler's Wobble larger than is has been since recording began. The drift of the locus of the spiral is now qute apparent. There is an apparent drift of some.04 as from 1945 to 1958, a period of 13 years. Polar Tracks 1903 to 1964 - Chart 509 Chart 509 plot of Chandler’s Wobble from 1903-1964 The 1958-1964 spiral suddenly becomes chaotic and jerky. My my, where h |
