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Thread: Ice Age

  1. #1 Ice Age 
    Forum Freshman Amy Smith's Avatar
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    Hi All,
    My name is Amy and this is my first post on this forum. I have viewed the post on the Ice Age and a few theory idea's here. I have a page of my own regarding the Ice Age cause and effect and wish to post it here. I have attempted to give references to supporting findings whenever possible.
    There are two seperate theories on this page. One theory is regarding an Ice Age flood which I propose washed away a Caribbean land area. The other theory regards a possible cause of the Ice Age and it's end.

    The page is at http://www.losthistorypublishing.com/Catastrophy.html



    Amy


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  3. #2  
    WYSIWYG Moderator marnixR's Avatar
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    aren't you referring to something totally different when you postulate a tilted earth during the latest ice age maximum ? the link you refer to tries to explain "snowball earth" about 800 million years ago, not any recent events

    "The sediments we have recovered from Norway offer the first good evidence that a true polar wander event happened about 800 million years ago," ...

    is there any evidence for a similar tilt in recent times ? because a green Sahara can easily be explained by weather and rainfall patterns without the need for a change in the tilt of the earth


    "Reality is that which, when you stop believing in it, doesn't go away." (Philip K. Dick)
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  4. #3 Ice Age 
    Forum Freshman Amy Smith's Avatar
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    marnixR


    "If the volcanoes, land and other masses that exist within the spinning Earth ever became sufficiently imbalanced, the planet would tilt and rotate itself until this extra weight was relocated to a point along the equator."

    This is the element of the quote that was of intrest to me. I needed to show that a spinning sphere wit an unevenly distributed mass can and will tilt to adjust for that mass. Mr. Maloof expressed this point and it was needed from a "scientist" as evidense to that effect. Evidently, a large number of scientist have not had the pleasure of baseball, softball or any ball that can become mishapen, warped or otherwise unbalanced and conformation from a more familar source was required for them. The above quote was for their benifit.
    More sports minded people such as myself would just use the Spitball reference in the article I posted.

    As to Mr. Maloof's Snowball Earth, it is an interesting theory but not one I follow.
    As to evidence the Earth tilted, other than the wash out effects I have used in the web page, the melted ice pack and the current tilt of the Earth, I have none.
    My page is simply a speculation of how we arrived at the point we find ourselves at.
    Thanks for your intrest in this article,

    Amy
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  5. #4 Re: Ice Age 
    Forum Cosmic Wizard SkinWalker's Avatar
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    Quote Originally Posted by Amy Smith
    Hi All,
    My name is Amy and this is my first post on this forum. I have viewed the post on the Ice Age and a few theory idea's here. I have a page of my own regarding the Ice Age cause and effect and wish to post it here. I have attempted to give references to supporting findings whenever possible.

    The page is at [url]http://www.losthistorypublishing.com/Catastrophy.html

    There is another page that uses text from Plato and the book of Noah at:

    http://www.losthistorypublishing.com/Atlantis.html

    This page is for those willing to except these works for any historical value they may have. At any rate I did a lot of research and work and had a lot of fun creating these pages. I hope you enjoy viewing them as much as I did making them.

    Amy
    I haven't had the time to do more than glance at the links, but I'm curious: in your hypothesis(es), do you first account for the more parsimonious explanations of previous glacial periods? There was no single "ice age," by the way -rather several warm/cold periods throughout the course of Earth's history.

    Also, in your second link, you say, "My only reason for refering [sic] to these two writings at all is because they are the only two ancient historical text that refer to the Earth having Tilted."

    Neither Plato's or the Noachian Flood myth are historical records, rather they are texts that exist in history. This is an important distinction for what you're describing.

    I'm currently swamped with work, but if I get an opportunity, I'll look them both over more thoroughly.
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  6. #5 Ice Age 
    Forum Freshman Amy Smith's Avatar
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    SkinWalker,
    Coleman"s continental rise, comets, earth core hot spots, Milankovitch Cycles, these just don't hold it for me. But that's just me. I'm sure others place a great deal of confidence in one or the other of these theories.
    About Noah Plato. They are on the Atlantis page for the more inclusive Ice Age explanations by those who do consider them historical..
    You may appreciate the Catastrophy.html page a little beter. There are no references to these works on that page.
    Thank you for checking out my webpage,
    Amy
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  7. #6 Re: Ice Age 
    WYSIWYG Moderator marnixR's Avatar
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    Quote Originally Posted by Amy Smith
    Coleman's continental rise, comets, earth core hot spots, Milankovitch Cycles, these just don't hold it for me.
    any particular reason(s) why not ?
    "Reality is that which, when you stop believing in it, doesn't go away." (Philip K. Dick)
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  8. #7  
    Forum Cosmic Wizard SkinWalker's Avatar
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    Indeed. Same question. There are other data which we could discuss as well, but, for now, let's discuss these bits since you brought them up. Why don't they "do it for [you]?" What data do you have that aren't convincing and what past research have you been involved in that shows how the data are not sufficient?
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  9. #8 Ice Age 
    Forum Freshman Amy Smith's Avatar
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    Thats a lot to answer to in a short forum post so let's just jump to the big guy on the block theory....
    Milutin Milankovitch

    "One of the fundamental tenets of palaeoclimate modeling, the Milankovitch theory, is called into doubt by isotope analysis of a calcite vein, just reported in Science by Winograd and colleagues. The theory, which is backed up by a compelling bank of evidence, suggests that the ice ages determined, with unprecedented accuracy, in the new record cannot be reconciled with the planetary cyclicity. . .
    Winograd and colleagues' evidence also turns on oxygen isotope data, this time from vein calcite coating the hanging wall of an extensional fault at Devils Hole, an aquifer in southern Nevada. In 1988, the authors published a date, 145,000 years, based on 234U-230Th dating for the end of the penultimate ice age (Termination II), marked by an increase in the 18O to 16O ratio, a change taken to mirror an increase in local precipitation. Although the date was only 17,000 year earlier than the previously accepted date of 128,000 years, if correct, this change is enough to bring Milankovitch mechanism into serious doubt. . .
    I remain confused. The geochemist in me says that Devils Hole chronology is the best we have. And the palaeoclimatologist in me says that correlation between accepted marine chronology and Milankovitch cycles is just too convincing to be put aside. . .
    One side will have to give, and maybe - just to be safe - climate modellers should start preparing themselves for a world without Milankovitch." 1
    http://www.detectingdesign.com/milankovitch.html

    The above article is one of many found on the internet relating to Milankovitch.
    From my personal perspective, I simply can't visualize enough variations in temperatures in the Milankovitch theory to account for the Ice Ages. That is a personal obsevation from my understanding of the theory. I have studied his theory in some depth, but I am willing to concede that my understanding may not be complete.

    Comet/Asteroid: A big rock did it. Sounds to much like the "Gnomes did it theory"
    (When a cause can't be discerned, assign it to the usual suspect)

    The only research I do is my own studies of material about the Ice Age. I admit I fall short of scholastic abilities for other peoples requirements.

    From my perspective, the theory I propose is no different than the others. It's basic tenant: "A spinning sphere with an unequal distribution of mass will tilt due to the forces of that mass"... is supported by the laws of Physic's. If I could prove that this event occured, it would no longer be theory.

    I can say having read your post, You folks obviously have your act together on these things.

    "One side will have to give, and maybe - just to be safe - climate modellers should start preparing themselves for a world without Milankovitch."
    And a world with

    AMY (Aren't I just so full of myself)
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  10. #9  
    Administrator KALSTER's Avatar
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    In the above theory I presume the Earth "Tilted" as much as 30 to 40 degrees due to the off balance weight of the Glacial Ice Sheet. This tilt moved the ice sheet into more direct sunlight and caused a rapid meltoff and huge flooding. As the Ice Sheet melted the Earth reset it's self to it's present 23.5 degrees.
    The earth's axis of rotation is not a straight line, but it has a slight wobble in it, called the Chandler wobble or more generally, Polar motion. It means that the earth actually spins around a focal node with the two parts of the line above and below it forming a cone shape. In my mind what a build-up of mass in the northern hemisphere would do, like the one you are suggesting, is to simply move the focal point a bit to the south thereby increasing the wobble slightly. The operative word is slightly though IMHO, judging from the percentage of the total mass of the earth that mass of ice would represent.

    That is, if I understand it correctly. :?
    Disclaimer: I do not declare myself to be an expert on ANY subject. If I state something as fact that is obviously wrong, please don't hesitate to correct me. I welcome such corrections in an attempt to be as truthful and accurate as possible.

    "Gullibility kills" - Carl Sagan
    "All people know the same truth. Our lives consist of how we chose to distort it." - Harry Block
    "It is the mark of an educated mind to be able to entertain a thought without accepting it." - Aristotle
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  11. #10 Re: Ice Age 
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    Quote Originally Posted by Amy Smith
    marnixR


    "If the volcanoes, land and other masses that exist within the spinning Earth ever became sufficiently imbalanced, the planet would tilt and rotate itself until this extra weight was relocated to a point along the equator."

    This is the element of the quote that was of intrest to me. I needed to show that a spinning sphere wit an unevenly distributed mass can and will tilt to adjust for that mass. Mr. Maloof expressed this point and it was needed from a "scientist" as evidense to that effect. Evidently, a large number of scientist have not had the pleasure of baseball, softball or any ball that can become mishapen, warped or otherwise unbalanced and conformation from a more familar source was required for them. The above quote was for their benifit.
    More sports minded people such as myself would just use the Spitball reference in the article I posted.

    As to Mr. Maloof's Snowball Earth, it is an interesting theory but not one I follow.
    As to evidence the Earth tilted, other than the wash out effects I have used in the web page, the melted ice pack and the current tilt of the Earth, I have none.
    My page is simply a speculation of how we arrived at the point we find ourselves at.
    Thanks for your intrest in this article,

    Amy
    Amy,

    spitballs notwithstanding (and which are more about differences in airflow than mass imbalance - fast bowlers in cricket get the same effect by continuously polishing one half of the ball), you have a few problems with the "imbalance/tilt" idea ...

    the crust of the Earth represents less than 1% of its radius, and is the least dense of the solid layers ...

    unlike any thrown ball analogy, the most proximal dominant centre of gravity is within the Earth; if it wasn't, the northern hemisphere would be completely tilted towards the sun ...

    the ice cap of North America is more than balanced by the Siberian ice cap; add Greenland and Europe, and you have ice pretty evenly spread around the northern half of the globe, and a smaller but similarly balanced ice cover in the south ...

    the Gulf of Mexico is indeed an oceanic remnant - the Central American isthmus isolated the Gulf and the Caribbean from the Pacific Ocean about 42,000 yrs ago - eventually, it will become like the Black Sea (a remnant of the Tethyan Sea which is now all but landlocked) ...

    the substantial collection of sediments along the Eastern Seaboard have been studied, and core-sampled, and have been described as eroded and transported sediments from the Appalachian Mountains ...

    the "tilt" of the Earth is recorded in magnetic deposits; the largest of these line the ocean floors ... a shift in the tilt to 30 or 40 degrees at anytime in the past 150 million years would be noticed - indeed, it would be headline news in every major scientific publication ...
    Nature abhors perfection; cats abhor a vacuum.

    "I don't know; I'm making it up as I go ..." Dr H Jones (Jr).
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  12. #11 Ice Age 
    Forum Freshman Amy Smith's Avatar
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    KALSTER

    The Earths Moon orbits the Earth from 20 to 30 degrees off from the Earth's equator because the Earth tilts at 23.5 degrees. The Moon is only five degrees off from the eliptic of the sun. I believe the Earth once sat with only a five degree difference as well. That would mean that the Moon once circled the Earth at or near the equator.
    This two mile thick ocean of ice over the North American continent not only moved because of it's own weight. Just as the moon today draws the oceans towards it with it's gravity creating the tides, it also drew this ocean of ice. It was, in my opinion, a factor in the tilt of the Earth at the end of the Ice Age.
    Another factor was the oceans were as much as 300 to 500 ft lower than today (Depending on who's estimates you use) which also altered the weight dynamics. To me, all of these factors came together at the right moment to cause the present tilt of the Earth. This is just my view. I have "NO" evidence to support this claim.
    This is part of the reason I see a greater movement in the tilt of the Earth than the slightly you refered to. There are other factors to be sure.

    Thanks for the post
    Amy
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  13. #12 Ice Age 
    Forum Freshman Amy Smith's Avatar
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    Cran

    WOW! Too many objections for me to respond to. But I will deal with two of them.

    the "the ice cap of North America is more than balanced by the Siberian ice cap; add Greenland and Europe, and you have ice pretty evenly spread around the northern half of the globe, and a smaller but similarly balanced ice cover in the south ...

    12,000 years ago Russian Siberia teemed with life. Witness the many animals being uncovered there today (which are frozen solid by the way) such as the Mammoth. If it were a two mile thick ice cap nothing could have lived there.
    Ice in the south: The Patagonian ice sheet extended into South America as far as Argintina and into Peru. Even more to tug that ball.

    tilt" of the Earth is recorded in magnetic deposits; the largest of these line the ocean floors ... a shift in the tilt to 30 or 40 degrees at anytime in the past 150 million years would be noticed - indeed, it would be headline news in every major scientific publication ...

    True as far as it goes. These magnetic recordings are locked in rock. The tilt I am refering to was only 12,000 years ago and was short lived. Not enough time for a locking to occur or be deposited in any useful amount on the ocean floor..

    Hope to see you soon in those
    major scientific publications

    Thanks for the post
    Amy
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  14. #13  
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    The Earths Moon orbits the Earth from 20 to 30 degrees off from the Earth's equator because the Earth tilts at 23.5 degrees. The Moon is only five degrees off from the eliptic of the sun. I believe the Earth once sat with only a five degree difference as well.
    The most plausible current theory for the origin of the moon is of a Mars-sized mass slamming into the proto-earth +- 4.5 billion years ago. This impact most probably had the current configuration as result, or something close to it.

    The wobble of the axis due to local imbalances act towards creating a wobble in the axis, not in actually tilting the axis relative to the orbital plane. Put more clearly: the wobble due to short term imbalances (atmosphere, snow accumulation, ocean currents, etc) traces out an irregular spiral over 14 months of only between 10 to 50 feet.

    The process you seem to be describing is called true polar wander. Most significantly, though, this represents a shift of the earth’s crust and mantle, while the tilt of the axis relative to the orbital plane remains constant. One of the quotes you supplied on your webpage stops short of a further illumination that immediately invalidates an axial tilt precession:

    “ScienceDaily (Aug. 25, 2006)-
    ...... By analyzing the magnetic composition of ancient sediments found in the remote Norwegian archipelago of Svalbard, Princeton University's Adam Maloof has lent credence to a 140-year-old theory regarding the way the Earth might restore its own balance if an unequal distribution of weight ever developed in its interior or on its surface.

    The theory, known as true polar wander, postulates that if an object of sufficient weight -- such as a supersized volcano -- ever formed far from the equator, the force of the planet's rotation would gradually pull the heavy object away from the axis the Earth spins around. If the volcanoes, land and other masses that exist within the spinning Earth ever became sufficiently imbalanced, the planet would tilt and rotate itself until this extra weight was relocated to a point along the equator-...................-Polar wander can tip the entire planet on its side at a rate of perhaps several meters per year, about 10 to 100 times as fast as the continents drift due to plate tectonics. Though the poles themselves would still point in the same direction with respect to the solar system, the process could conceivably shift entire continents from the tropics to the Arctic, or vice versa, within a relatively brief geological time span.”

    Current estimates of the rate of true polar wander is much slower than would have been required for your hypothesis and even this rate requires much larger imbalances than a single ice sheet, like the position of a super-continent or the emergence of a super-volcano.
    Disclaimer: I do not declare myself to be an expert on ANY subject. If I state something as fact that is obviously wrong, please don't hesitate to correct me. I welcome such corrections in an attempt to be as truthful and accurate as possible.

    "Gullibility kills" - Carl Sagan
    "All people know the same truth. Our lives consist of how we chose to distort it." - Harry Block
    "It is the mark of an educated mind to be able to entertain a thought without accepting it." - Aristotle
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  15. #14 Ice Age 
    Forum Freshman Amy Smith's Avatar
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    When I was in the fourth or fifth grade I checked out of the school library a book that I can't remember the title of now. It postulated that when the Earth was still a molten ball of spinning magma a bulge developed that spun off and became our moon. As a side note, I did a book report on it and failed because the teacher said I didn't read a book but made up one. And a crazy one at that. (I didn't make it up by the way) Also, not too shabby for a fourth or fifth grader to make up a theory like that, and I was very detailed about it because it entrigued me.

    My point is, there are as many theories as there are people to make them. If I were going to follow a theory on the moon though, that would be the one I follow as I am still entrigued by it..

    I'm really not into the "A big rock did it thing" or "asteroid impact". It has been used way to much. It is the second of the two prerequisites if you wish to have an accepted theory in scientific circles.

    You say it would require a Super continent to cause the Earth to tilt. The Glacial ice mass covered all of Canada from Alaska down to the tip of Illinois. Then back up through New England, across Greenland and the northern half of Europe. Then back across the Artic to Alaska. And on top of that it sat two miles above the land mass it rested on. A "Super" Continent of ice.

    I apologize, but shomehow I don't follow you on how the quote I made went on to cancel it's self out so I can't answer to that point. I do know the only part of the quote that intrested me was that A spinning sphere with an off balance mass will tilt and rotate it's self to try and balance out the mass.

    Interesting observations though,
    Amy
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  16. #15 Re: Ice Age 
    WYSIWYG Moderator marnixR's Avatar
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    Quote Originally Posted by Cran
    the ice cap of North America is more than balanced by the Siberian ice cap; add Greenland and Europe, and you have ice pretty evenly spread around the northern half of the globe, and a smaller but similarly balanced ice cover in the south
    as far as i'm aware Siberia never built up the mile-high glaciers that were observed in Canada, Greenland and north-western Europe, presumably something to do with not enough humidity making it over the Himalayas

    so there definitely was an imbalance in ice coverage in the northern hemisphere
    whether this is sufficient to exacerbate the earth's wobble is altogether a different thing ...
    "Reality is that which, when you stop believing in it, doesn't go away." (Philip K. Dick)
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  17. #16  
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    My point is, there are as many theories as there are people to make them. If I were going to follow a theory on the moon though, that would be the one I follow as I am still entrigued by it..
    You can follow whatever hypothesis you like, but the fact is that some hypothesis are more likely than others and the current, widely supported one of the moon being the result of a collision is the most likely so far due to supercomputer simulations. Impacts are a fact of accretion. It is undeniable that they occurred, frequently at first and less so as time went on and it is also undeniable that they would of affected the earth profoundly. You can't simply sweep away a theory because you don't like it in a vague way or because it is in opposition to your own hypothesis that you dreamt up in the fourth grade. Your idea is called the Fission hypothesis and fails because it would have required too great an initial spin and would have positioned the moon's orbit on the equatorial plane. Look HERE for a few hypothesis.


    You say it would require a Super continent to cause the Earth to tilt. The Glacial ice mass covered all of Canada from Alaska down to the tip of Illinois. Then back up through New England, across Greenland and the northern half of Europe. Then back across the Artic to Alaska. And on top of that it sat two miles above the land mass it rested on. A "Super" Continent of ice.
    Maybe so, but like I said, true polar wander takes place over the course of millions of years, not mere decades. This is borne out by evidence. Secondly, while that ice would have caused an imbalance, it is still small relative to the entire mass of the continents. The type of super continent I am talking about is something like Pangaea. Your proposed imbalance could quite possibly have caused some true polar wander, but, by my estimation and based on evidence of past polar wander events, it would have happened by orders of magnitude slower than you are proposing. Also, the ice does not form part of the crust, so a lot of the energy would have been taken up by glacial movement relative to the bedrock and by migration over open water IMO.

    I apologize, but shomehow I don't follow you on how the quote I made went on to cancel it's self out so I can't answer to that point. I do know the only part of the quote that intrested me was that A spinning sphere with an off balance mass will tilt and rotate it's self to try and balance out the mass.
    I don't see how you couldn't, as I even bolded the most relevant part. True polar wander does not affect the axial tilt relative to the earth's orbital plane, the ecliptic. What happens is that the earth's crust and mantle moves around, while the core stays stationary. This is more or less the only affect terrestrial surface mass can have, while off-earth masses are responsible for true precession, nutation, etc. If the crust was fixed it might have been a different story (still not yours though), but it isn't.

    Imagine a nail sticking out of your desk. The nail passes through a metal ball bearing and exits on the other side. Now imagine covering the ball bearing with molasses and then applying a layer of clay over it. Now you have a rough model of crust, core and mantle. If you added a gob of clay somewhere above the equator and started to spin the whole setup, you would see true polar wander take place. The clay would re-orientate itself, but the axis (nail) relative to the ecliptic (desk) would stay constant.
    Disclaimer: I do not declare myself to be an expert on ANY subject. If I state something as fact that is obviously wrong, please don't hesitate to correct me. I welcome such corrections in an attempt to be as truthful and accurate as possible.

    "Gullibility kills" - Carl Sagan
    "All people know the same truth. Our lives consist of how we chose to distort it." - Harry Block
    "It is the mark of an educated mind to be able to entertain a thought without accepting it." - Aristotle
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  18. #17 Ice Age 
    Forum Freshman Amy Smith's Avatar
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    I don't see how you couldn't, as I even bolded the most relevant part. True polar wander does not affect the axial tilt relative to the earth's orbital plane, the ecliptic. What happens is that the earth's crust and mantle moves around, while the core stays stationary. This is more or less the only affect terrestrial surface mass can have, while off-earth masses are responsible for true precession, nutation, etc. If the crust was fixed it might have been a different story (still not yours though), but it isn't.
    Sounds a lot like the Charles Hapgood Crustal Displacement Theory. I find this theory interesting as well even though it has been mostly disregarded.
    Amy
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  19. #18 Re: Ice Age 
    WYSIWYG Moderator marnixR's Avatar
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    Quote Originally Posted by Amy Smith
    I don't see how you couldn't, as I even bolded the most relevant part. True polar wander does not affect the axial tilt relative to the earth's orbital plane, the ecliptic. What happens is that the earth's crust and mantle moves around, while the core stays stationary. This is more or less the only affect terrestrial surface mass can have, while off-earth masses are responsible for true precession, nutation, etc. If the crust was fixed it might have been a different story (still not yours though), but it isn't.
    Sounds a lot like the Charles Hapgood Crustal Displacement Theory.
    no it doesn't - Charles Hapgood's theory indicates a movement of hundreds of miles in the space of less than a thousand years, whereas what kalster talks about is presumably plate tectonics, which happens at a speed of about 5mm/year

    i'd say that indicates a vast difference in mechanism
    "Reality is that which, when you stop believing in it, doesn't go away." (Philip K. Dick)
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  20. #19 Re: Ice Age 
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    Quote Originally Posted by Amy Smith
    Cran

    WOW! Too many objections for me to respond to. But I will deal with two of them.

    the "the ice cap of North America is more than balanced by the Siberian ice cap; add Greenland and Europe, and you have ice pretty evenly spread around the northern half of the globe, and a smaller but similarly balanced ice cover in the south ...

    12,000 years ago Russian Siberia teemed with life. Witness the many animals being uncovered there today (which are frozen solid by the way) such as the Mammoth. If it were a two mile thick ice cap nothing could have lived there.
    Ice in the south: The Patagonian ice sheet extended into South America as far as Argintina and into Peru. Even more to tug that ball.
    I stand corrected re the Last Glacial Maximum - I was thinking of earlier Eurasian glacial advances -

    from http://gsa.confex.com/gsa/inqu/final...ract_53012.htm
    XVI INQUA Congress
    Geological Society of America Abstracts with Programs, , p. 195
    LATE QUATERNARY ICE SHEET HISTORY OF NORTHERN EURASIA
    SVENDSEN, John Inge, Department of Earth Science, Univ of Bergen, Allegt. 41, Bergen N-5007 Norway, John.Svendsen@geol.uib.no.

    The limits of the Eurasian ice sheets have been reconstructed for four glaciations during the Quaternary: 1) the Late Saalian (c. 160-140 ka) 2) the Early Weichselian (90-80 ka), 3) the early Middle Weichselian (60-50 ka) and 4) the Late Weichselian (20-15 ka)... A huge glaciation that covered vast areas of northern Eurasia occurred during the Late Saalian (MIS 6) just prior to the last interglacial. The maximum extent of the post-Eemian glaciation in the Eurasian Arctic occurred around 90-80,000 years ago (Early Weichselian MIS 5b), when the Barents-Kara Ice Sheet expanded far onto northern Russia and Siberia and blocked the northbound draiange towards the Arctic Ocean. A regrowth of the ice sheets occurred during the early Middle Weichselian, culminating about 60-50,000 years ago.

    During the Last Glacial Maximum (LGM) around 22-17,000 years ago the Scandinavian Ice Sheet attained its maximum position. At this time the Barents-Kara Ice Sheet embraced a much smaller area over the Russian Arctic than shown in most earlier reconstructions. The proposed ice sheet history in the Barents- and Kara Sea region is supported by core data from the Arctic Ocean. In the Arctic Ocean sediments the ice sheet maxima are recognized as layers with a high concentration of ice rafted debris (IRD) and the deglaciations are seen as meltwater spikes from the oxygen isotope record. A comparison of empirical ice sheet reconstruction with glaciological model simulations suggest that that the Eurasian ice sheets during the Quaternary to a large extent can be explained by the interaction of sea level regressions, negative shifts in isolation and regional variations in precipitation rates.
    Even so, the glacial contribution to mass imbalance is less than that caused by slab subduction around the Pacific Rim ...
    .........


    Quote Originally Posted by Amy Smith
    tilt" of the Earth is recorded in magnetic deposits; the largest of these line the ocean floors ... a shift in the tilt to 30 or 40 degrees at anytime in the past 150 million years would be noticed - indeed, it would be headline news in every major scientific publication ...

    True as far as it goes. These magnetic recordings are locked in rock. The tilt I am refering to was only 12,000 years ago and was short lived. Not enough time for a locking to occur or be deposited in any useful amount on the ocean floor..
    Oh, plenty of time, actually* ... and not just on ocean floors ...

    from - http://www.volcanolive.com/vei.html

    About 50-60 volcanoes erupt every year.
    20-30 are effusive (lava flows), 20-30 are explosive.
    from - http://www.geocities.com/capecanaver.../magfield.html
    In virtually all igneous rocks there are varying amounts of the mineral magnetite. When igneous rocks crystallize there temperatures are in excess of 900 degrees Celsius. At these temperatures, the atoms in the minerals have a large amount of energy and are being shaken. The vibrating, shaking atoms are unable to line up until more cooling occurs. At approximately 578 degrees Celsius, the Curie temperature for magnetite, enough energy is lost to allow the atoms to come into alignment with the earth's magnetic field. At tens of degrees below the Curie temperature the blocking temperature is reached and the alignment of the minerals becomes permanent. Another way to understand TRM is to think of the tiny magnetite crystals as compass needles that become frozen in place as the rock cools thus recording the magnetic inclination of the earth's magnetic field at the time of their formation. The Peninsula Ranges Batholith in Southern and Baja California have consistently shown shallow inclinations compared to its present location. A 900 km movement south of its present location would account for these shallow inclinations.
    *if by "short-lived", you are saying that this tilting occurred in less time than it takes surface igneous deposits to solidify, then you should be able to point to the tremendous ruptures (earthquakes, tectonic shifts) that would have accompanied the event ...

    Did the "tilt" affect all surface tectonic plates, or only the ice-weighted ones?

    Were there even greater tilts caused by the earlier, more extensive glaciations?
    If not, why not?

    How much rotational energy (in terms of seconds/minutes/hours added to daily rotation times) was lost due to glacial compression of the crust, and by "tilting"?


    Quote Originally Posted by Amy Smith
    Hope to see you soon in those
    major scientific publications

    Thanks for the post
    Amy
    Perhaps you will, Amy, but not through rehashing ideas discredited long ago ...
    Nature abhors perfection; cats abhor a vacuum.

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  21. #20  
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    Sounds a lot like the Charles Hapgood Crustal Displacement Theory.
    His stuff, as marnixR said, is more radical and is not supported by much evidence. True polar wander, though, has a lot going for it and their is direct evidence of past occurences (LINK & LINK(PDF)) where a large degree of polar wander took place and it has been directly observed on other celestial bodies, like Europa.

    whereas what kalster talks about is presumably plate tectonics, which happens at a speed of about 5mm/year
    Not exactly. True polar wander is the shift of the entire crust + mantle at once due to a mass imbalance. The rate of this shift is in the order of 10 to 100 times the speed of continental drift.

    The most generous estimate of the speed of continental drift I could find is 5 - 10cm/year. If you take the upper bounds of these speeds (i.e. 10cm/year x 100), then that gives a movement of 10m/year. For the earth to have tilted , according Amy's most conservative estimate, it would have taken about 700 years. The thing is, there would be no reason for this to "reset" after the ice has melted, as no imbalance would have remained.

    Some questions:

    1)Why would the ice sheets over Europe not have provided counter weight to the North American ice sheets?
    2)Have you taken the movement of the other continents during this proposed shift into account at all?
    Disclaimer: I do not declare myself to be an expert on ANY subject. If I state something as fact that is obviously wrong, please don't hesitate to correct me. I welcome such corrections in an attempt to be as truthful and accurate as possible.

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  22. #21 Ice Age 
    Forum Freshman Amy Smith's Avatar
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    KALSTER
    Cran
    marnixR
    and others

    I can't tell you how much I appreciate all the time you have put into the research you have done. It is information that is very important to me whether you are for or against an Earth tilt. I can put to use everything you have shown me. I don't even know how to word a search for some of the material you have produced.

    KALSTER
    .
    "The most generous estimate of the speed of continental drift I could find is 5 - 10cm/year. If you take the upper bounds of these speeds (i.e. 10cm/year x 100), then that gives a movement of 10m/year. For the earth to have tilted , according Amy's most conservative estimate, it would have taken about 700 years. The thing is, there would be no reason for this to "reset" after the ice has melted, as no imbalance would have remained."

    This is paticularly useful as it may prompt a revision in my theory. If the Earth sat at 5.5 degrees, about the same as the Moons relation to the sun's eliptic, and tilted to it's present 23.5 degrees (an 18 degree tilt) It would take around 400 years.
    An 18 degree tilt in 400 years would give me more than enough rapid melt-off with water back-up and ice dam collapses to account for the flooding of the Gulf and Caribbean areas.

    I really appreciate al of this useful info.
    Amy
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  23. #22  
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    I can't tell you how much I appreciate all the time you have put into the research you have done. It is information that is very important to me whether you are for or against an Earth tilt. I can put to use everything you have shown me. I don't even know how to word a search for some of the material you have produced.
    It has been an interesting learning curve for me too. :wink:

    This is paticularly useful as it may prompt a revision in my theory. If the Earth sat at 5.5 degrees, about the same as the Moons relation to the sun's eliptic, and tilted to it's present 23.5 degrees (an 18 degree tilt) It would take around 400 years.
    An 18 degree tilt in 400 years would give me more than enough rapid melt-off with water back-up and ice dam collapses to account for the flooding of the Gulf and Caribbean areas.
    You need to answer some questions though, including the two I posted last.

    Also, when you say the tilt was at 5.5 (again ignoring the fact that your moon formation hypothesis is unsupported by evidence), you must remember that the tilt of the axis would still have been +- relative to the ecliptic. If true polar wander had taken place, it would mean that the pole was at another geographical location. So, where do you think it was?

    You seem to keep missing the point that a mass imbalance would not have shifted the axial tilt, but could have caused true polar wander at most.
    Disclaimer: I do not declare myself to be an expert on ANY subject. If I state something as fact that is obviously wrong, please don't hesitate to correct me. I welcome such corrections in an attempt to be as truthful and accurate as possible.

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  24. #23 Ice Age Theory 
    Forum Freshman Amy Smith's Avatar
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    I am not saying Crustal Displacment or Polar Wander. I am saying there was an actual Axis Shift. No geograpical relocation of the poles. The entire planet leaned over as one mass.
    All of the following statements are not mine. They come from other sources. The first ask what caused the tilt of the Earth's Axis.

    Environmental Earth Science Archive

    Question - What causes the tilt of the Earth's axis? Is it the result
    of the sun's and moon's gravity? Why is it 23.5 degrees?

    "This is a question that has been pondered by many scientists in the past and is to the present. The locations and gravity of the other planets,
    the Sun, and the Moon may have had some effect on the tilt of the Earth. However, a recent theory says that the shape of the Earth has had more of an effect on the tilt angle in the past. The shape may have been sufficiently altered by the massive ice sheets that have formed during ice ages to cause a change in the tilt. At least that is one theory.
    You can demonstrate this effect by adding a small piece of bubble gum to a ball (near its top but not at the pole itself); attempt to spin the ball and see what effect it has on the rotation and tilt of the ball. As ice accumulated at the North Pole and over the Northern Hemispheres during the ice ages, it may have changed the tilt in the same way, but much more slowly with time." You can find this article at:
    Ask A Scientist

    Department of Physics at the University of Illinois.

    "The Earth has not always rotated at 23.5 degrees. Many factors effect the angle of Earths tilt. The motion of large air masses can change its tilt by measurable amounts even today. During the major Ice Ages, large sheets of ice on Earths surface and lowered sea level may have caused the Earth to have an even larger tilt."

    You can find this article at:
    University of Illinois


    This is the point I am trying to make.

    Thanks
    Amy
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    Then you are plum out of luck. For the axial tilt relative to the ecliptic to change requires an external torque, like the gravitational pull of the moon and the sun. This does not happen at the same rate as true polar wander. It takes many thousands to millions of years.
    Disclaimer: I do not declare myself to be an expert on ANY subject. If I state something as fact that is obviously wrong, please don't hesitate to correct me. I welcome such corrections in an attempt to be as truthful and accurate as possible.

    "Gullibility kills" - Carl Sagan
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  26. #25 Ice Age 
    Forum Freshman Amy Smith's Avatar
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    Department of Physics at the University of Illinois.

    "The Earth has not always rotated at 23.5 degrees. Many factors effect the angle of Earths tilt. The motion of large air masses can change its tilt by measurable amounts even today. During the major Ice Ages, large sheets of ice on Earths surface and lowered sea level may have caused the Earth to have an even larger tilt." You can find this article at:
    http://van.physics.illinois.edu/qa/listing.php?id=1019 University of Illinois

    The above is one of the most profound statements yet. If a mass of "AIR" can alter the tilt of the Earth, is it that difficult to believe that a Continent of Ice could do it?

    Amy
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  27. #26  
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    I am not disputing that it can happen, I am disputing that it can happen at the rates you require. Those rates I calculated earlier is for true polar wander, not axial tilt. Like I said, for axial tilt to change requires that the moon, the sun, etc. has to effect a torque on the rotating earth. The earth by itself can not do it. The most it could do is affect the Chandler wobble and true polar wander in the shorter term.

    Here is the full paragraph from the source you quoted above:

    "The Earth has not always rotated at 23.5 degrees. Many factors effect the angle of Earth’s tilt. The motion of large air masses can change its tilt by measurable amounts even today. During the major Ice Ages, large sheets of ice on Earth’s surface and lowered sea level may have caused the Earth to have an even larger tilt. Small changes in the Earth’s surface like continental drift and variations of sea level acting over million of years time may change the tilt significantly."

    and again a further part of another source you provided earlier:

    "ScienceDaily (Aug. 25, 2006)-
    ...... By analyzing the magnetic composition of ancient sediments found in the remote Norwegian archipelago of Svalbard, Princeton University's Adam Maloof has lent credence to a 140-year-old theory regarding the way the Earth might restore its own balance if an unequal distribution of weight ever developed in its interior or on its surface.

    The theory, known as true polar wander, postulates that if an object of sufficient weight -- such as a supersized volcano -- ever formed far from the equator, the force of the planet's rotation would gradually pull the heavy object away from the axis the Earth spins around. If the volcanoes, land and other masses that exist within the spinning Earth ever became sufficiently imbalanced, the planet would tilt and rotate itself until this extra weight was relocated to a point along the equator-...................-Polar wander can tip the entire planet on its side at a rate of perhaps several meters per year, about 10 to 100 times as fast as the continents drift due to plate tectonics. Though the poles themselves would still point in the same direction with respect to the solar system, the process could conceivably shift entire continents from the tropics to the Arctic, or vice versa, within a relatively brief geological time span."

    I can't help but think that you are purposefully misreading your own sources?

    You also still haven't provided a reason for why the ice shelfs on the Eurasian continent would not have provided a counter balance?
    Disclaimer: I do not declare myself to be an expert on ANY subject. If I state something as fact that is obviously wrong, please don't hesitate to correct me. I welcome such corrections in an attempt to be as truthful and accurate as possible.

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  28. #27 Re: Ice Age 
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    Quote Originally Posted by Amy Smith
    Thats a lot to answer to in a short forum post so let's just jump to the big guy on the block theory....
    Milutin Milankovitch

    "One of the fundamental tenets of palaeoclimate modeling, the Milankovitch theory, is called into doubt by isotope analysis of a calcite vein, just reported in Science by Winograd and colleagues. The theory, which is backed up by a compelling bank of evidence, suggests that the ice ages determined, with unprecedented accuracy, in the new record cannot be reconciled with the planetary cyclicity. . .
    Winograd and colleagues' evidence also turns on oxygen isotope data, this time from vein calcite coating the hanging wall of an extensional fault at Devils Hole, an aquifer in southern Nevada. In 1988, the authors published a date, 145,000 years, based on 234U-230Th dating for the end of the penultimate ice age (Termination II), marked by an increase in the 18O to 16O ratio, a change taken to mirror an increase in local precipitation. Although the date was only 17,000 year earlier than the previously accepted date of 128,000 years, if correct, this change is enough to bring Milankovitch mechanism into serious doubt. . .
    I also have problems with the Milankovitch Theory. I acknowledge it for predicting seasonal intensities, but that's all. It only accounts for the eccentricity as being a factor for which pole is closest to the sun when. I believe the same gravitational pulls that change the eccentricity also change the average orbit distance. More complicating yet, I believe we can have two periods in time with the same eccentricity, but different average distances to the sun. Rather than using 65N insolation to explain the historical changes, I think eccentricity has far more by itself than any other factor. Now with the way elliptical orbits work, in general, I believe higher eccentricity = lower average solar heat. This also corresponds better with the ice ages than 65 N insolation, if I read the graphs right.

    About every 400,000 years, we enter a period of almost 0 eccentricity. The next low point is in about 26,000 years.
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  29. #28 Ice Age 
    Forum Freshman Amy Smith's Avatar
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    "I can't help but think that you are purposefully misreading your own sources?"

    That must be it. Maybe it's one of those Freudian undergarment thingys.

    Look at the top of a globe. From Alaska, draw a line across through the North Pole and on across. That is one half of the globe. See where Greenland and Europe Are?

    The other half is Asia and the Pacific. Little or no Ice there.

    Let's agree to disagree.

    This is not an emotional issue with me. As I say on the website, some will accept it, some will not. It will take some period of time to knock a dent in the "Old Boys Club". My grandchildren may still be pushing this provocative, amazing, astounding, incredible, revealing new concept.
    (Just a joke. At my own idea)

    Amy
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  30. #29  
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    Let's agree to disagree.
    That will not do Amy. You have to account for the problems of your hypothesis for it to ever become more than a hypothesis. If you can't do it, it is dead. End of story. That is how science works.

    The reason the earth can't tip over by itself in the way you want it is because of simple physics that is incontrovertible. As the earth rotates the excess mass will tend to pull the globe over to one side, BUT once it rotates for another 12 hours it will tend to pull the globe over to the other direction. They cancel out as far as the tilt goes. Don't you see that?
    Disclaimer: I do not declare myself to be an expert on ANY subject. If I state something as fact that is obviously wrong, please don't hesitate to correct me. I welcome such corrections in an attempt to be as truthful and accurate as possible.

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  31. #30 Re: Ice Age Theory 
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    Quote Originally Posted by Amy Smith
    I am not saying Crustal Displacment or Polar Wander. I am saying there was an actual Axis Shift. No geograpical relocation of the poles. The entire planet leaned over as one mass.
    Aah ... now you've entered into a whole new realm, and you're asking earth scientists to ignore or overturn everything we've learned about plate tectonics and inner Earth dynamics ...

    Here's the problem (1) - the Earth is not one solid mass ... it is composed of a number of shells or layers, each with different properties -
    and two of them behave as fluids under pressure; the layers above and below them move more or less independently -
    ie, the inner core rotates slightly faster than the bulk planet; the fluid parts of the mantle exhibit fairly complex convection and plume dynamics;
    the crustal plates ride on a mobile asthenosphere, which is driven by both convection and rotational energies ...

    to argue that the "entire planet leaned over as one mass" then requires plausible and self-consistent new explanations for all of our seismic studies, and for the formation and motions of the crustal plates; because the plates do not all move in the same direction, nor at the same rate, a bulk tilt is going to affect each plate differently ...

    to argue that this occurred because of ice* on a continent causing mass imbalance, is to say that the crust (the thinnest, and least dense layer) drives the motions of the bulk planet ...

    *keep in mind that ice is slightly less dense than water - if you want to argue a mass-driven imbalance, why not the Pacific Ocean?

    Here's the problem (2) the idea is not new, though applying it to frozen water is a twist -
    the same result was proposed when all of the landmasses of the Earth were joined on one side of the planet - the Permian supercontinent of Pangaea ...
    but neither the magnetic nor tectonic evidence was there to support any change in the Earth's bulk motions ...

    ......

    It's sad but true that sometimes scientists make unsupportable claims, and call them theories (or worse, facts). As students, we are encouraged to question and challenge, to seek out the anomalies and find better explanations. To obtain a PhD, we must do these things. But to become part of the body of knowledge in science, such new ideas must undergo a process of review - to ensure that the idea is self-consistent, consistent with observation and experiment, and improves understanding of the subject.

    An unknown (but very large) number of ideas do not survive the review process - they fade quietly into obscurity - and some become notorious through publication before their failings were discovered ... this is much more common today than it was in previous centuries, because of the proliferation of public-consumption publications (commercial or vanity press printings) ...

    Amy, your idea is that growing continental ice caused the Earth to tilt over - you're not alone in that thought ... someone else's idea might be that melting continental ice (and post-glacial rebound) causes the Earth's tilt to change:

    http://wattsupwiththat.com/2009/08/2...n-earths-axis/
    ... The influx of fresh water from shrinking ice sheets also causes the planet to pitch over. Landerer and colleagues estimate that the melting of Greenlands ice is already causing Earths axis to tilt at an annual rate of about 2.6 centimetres and that rate may increase significantly in the coming years.

    Now, they calculate that oceans warmed by the rise in greenhouse gases can also cause the Earth to tilt a conclusion that runs counter to older models, which suggested that ocean expansion would not create a large shift in the distribution of the Earths mass.



    The team found that as the oceans warm and expand, more water will be pushed up and onto the Earths shallower ocean shelves. Over the next century, the subtle effect is expected to cause the northern pole of Earths spin axis to shift by roughly 1.5 centimetres per year in the direction of Alaska and Hawaii.

    The effect is relatively small. The poles not going to drift away in a crazy manner, Landerer notes, adding that it shouldnt induce any unfortunate feedback in Earths climate.



    And climate change can also affect the Earths spin. Previously, Landerer and colleagues showed that global warming would cause Earths mass to be redistributed towards higher latitudes.
    the above article was sourced from:

    http://www.newscientist.com/article/...rths-tilt.html
    The changing climate has long been known to move Earth's axis. The planet's north pole, for example, is migrating along 79 W a line of longitude that runs through Toronto and Panama City at a rate of about 10 centimetres each year as the Earth rebounds from ice sheets that once weighed down large swaths of North America, Europe, and Asia.

    The influx of fresh water from shrinking ice sheets also causes the planet to pitch over. Landerer and colleagues estimate that the melting of Greenland's ice is already causing Earth's axis to tilt at an annual rate of about 2.6 centimetres and that rate may increase significantly in the coming years...
    ..........


    The actual paper that led to those articles:

    Landerer, F. W., Jungclaus, J. H., Marotzke, J., 2009: Long-term polar motion excited by ocean thermal expansion, Geophys. Res. Lett. - under review.

    hasn't been peer-reviewed or published yet ...

    ..............


    Quote Originally Posted by Amy Smith
    All of the following statements are not mine. They come from other sources. The first ask what caused the tilt of the Earth's Axis.

    Environmental Earth Science Archive

    Question - What causes the tilt of the Earth's axis? Is it the result
    of the sun's and moon's gravity? Why is it 23.5 degrees?

    "This is a question that has been pondered by many scientists in the past and is to the present. The locations and gravity of the other planets,
    the Sun, and the Moon may have had some effect on the tilt of the Earth. However, a recent theory says that the shape of the Earth has had more of an effect on the tilt angle in the past. The shape may have been sufficiently altered by the massive ice sheets that have formed during ice ages to cause a change in the tilt. At least that is one theory.
    You can demonstrate this effect by adding a small piece of bubble gum to a ball (near its top but not at the pole itself); attempt to spin the ball and see what effect it has on the rotation and tilt of the ball. As ice accumulated at the North Pole and over the Northern Hemispheres during the ice ages, it may have changed the tilt in the same way, but much more slowly with time." You can find this article at:
    Ask A Scientist
    Good grief! One of my student papers is now a theory???

    In 1999, and again in 2001, I was discussing the Milankovitch cycles and why there are such huge gaps (>100 million years) between the major ice age eras; I proposed that oblation (sphericity - polar flattening/equatorial bulge) was the component which Milankovitch didn't include ... but the effect is the opposite to that suggested; that if anything, increased polar flattening would tend towards a reduction of tilt, not an increase ... although I was mostly looking at the Cryogenian (so-called "Snowball Earth") glaciations, not the Pliocene-Pleistocene ...


    Quote Originally Posted by Amy Smith
    University of Illinois.

    "The Earth has not always rotated at 23.5 degrees. Many factors effect the angle of Earths tilt. The motion of large air masses can change its tilt by measurable amounts even today. During the major Ice Ages, large sheets of ice on Earths surface and lowered sea level may have caused the Earth to have an even larger tilt."

    You can find this article at:
    University of Illinois


    This is the point I am trying to make.

    Thanks
    Amy
    A lot of things have been suggested to explain the minor oscillations within the overall obliquity cycle - including ENSO (El Nino-Southern Oscillation) and sunspots ... when a scientist uses words like "may", it's speculation ...
    Nature abhors perfection; cats abhor a vacuum.

    "I don't know; I'm making it up as I go ..." Dr H Jones (Jr).
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  32. #31 Ice Age 
    Forum Freshman Amy Smith's Avatar
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    but the effect is the opposite to that suggested; that if anything, increased polar flattening would tend towards a reduction of tilt, not an increase ...
    and all the while tidal action slows down the spin thus causing the wobble to increase.

    What's up with this "a little more water in the big pond may tilt the Earth thingy.
    Interesting, a 10.000 foot elevated continent of ice, uhh uhh! But some more pond water, ok. Oh wait, I get it now. A "Scientist" said it.

    This is sort of like going to court. You had better have enough money to rent a good attorney. I need enough to rent a good scientist to make the case. I see now this theory probably never will take off. I don't have that kind of jack.

    But not to worry. I reworked my page.

    Amy
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  33. #32 Re: Ice Age 
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    Quote Originally Posted by Amy Smith
    but the effect is the opposite to that suggested; that if anything, increased polar flattening would tend towards a reduction of tilt, not an increase ...
    ...
    What's up with this "a little more water in the big pond may tilt the Earth thingy.
    Interesting, a 10.000 foot elevated continent of ice, uhh uhh! But some more pond water, ok. Oh wait, I get it now. A "Scientist" said it...

    Amy
    Not quite ...
    although a cubic mile of seawater is denser (heavier) than a cubic mile of ice, the difference in mass relationships goes a bit deeper than that ...

    if you're interested, take a look at a global gravimetric or gravity anomaly map - you'll find that the gravity "highs" (radial cones of greatest density) coincide with the abyssal plains of the world's oceans, while the "lows" coincide with continent-continent convergences (eg, the Himalayan Mountains) ...

    the Pacific Ocean, for all of its size, is only about 200 million years old; the Southern Atlantic is younger at roughly 150 million years; the Austral-Antarctic portion of the Southern Ocean is younger still at less than 100 million years - the oldest parts of the continents are around ten to twenty times these ages - it is the growth and subduction of the oceanic plates which drive the continents to where they are, and where they will be ... and the Earth's oceans make up nearly 70% of the surface ...

    and the divergent zones (so-called "spreading centres") are driven from below, not from the surface ...

    for the "gum on the ball" analogy to hold up, the gum would need to be flattened out until it is around 0.05% of the radial thickness - that's what 10,000 ft (3000 m) represents on the Earth - and the ball would have to be a cannonball wrapped in stone, then soaked in water ... and then it would have to be spun in space ...

    the reason the wobble increases on a spinning ball or top on Earth is because the centre of gravity between the object and the Earth lies well outside of the ball or top ... that's not the case with the Earth and its surface ...
    Nature abhors perfection; cats abhor a vacuum.

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  34. #33  
    Administrator KALSTER's Avatar
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    Not to mention it happens in the very short term, like 24 hours. The average tilt relative to the ecliptic stays the same.
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