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Rapid cooling 12700yrs ago

  1. Aug 7, 2008 #1


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    ScienceDaily (Aug. 4, 2008) — Researchers in Germany, Switzerland, and the United States have shown, for the first time, that an extremely fast climate change occurred in Western Europe. This took place long before human-made changes in the atmosphere, and is causatively associated with a sudden change in the wind systems.

    Now that is frightening.
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  3. Aug 7, 2008 #2


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    Wasn't the ice retreating in europe 12,700 BP? I thought the maximum extent for the Wisconsin/Wurm ice age was about 20,000BP.

    It's been thought for a while that ice ages can start very quickly, but I didn't realise it was down to a few years!
  4. Aug 7, 2008 #3
    Please notice the cooling element.


    This is extremely important. Achim Brauer published 3 earlier articles about the Meerfelder maar, the most outstanding high resolution record for the Younger Dryas, Pollen analysis shows a quick and distinct shift from abundant boreal forest type to arid steppe around 12,680 "varve" years BP. But "cold" is not reflected in the plant species. In the previous article, Lücke and Brauer 2004, mention "warmer summers". See:


    Considering that 12,700 true calendar years is just about 10,700 radio carbon (14C) years ago, compare that with:


    [quote]...Two very significant climatic [b]warming events[/b] (centered around 12,400 14C yr BP and [b]~10,700 14C yr BP[/b] respectively) correspond with the observed major changes in diatom assemblages....[/quote]

    Hence That cooling is highly ambigeous
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  5. Aug 7, 2008 #4


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    Not sure of my sources on this as it has been some years since I read it. Have they not found Mammoths with nearly intact vegetation in their digestive system. The understanding that I came away with was that the living animal had to have been nearly flash frozen to explain the state of preservation. The remains were found in what is now the Arctic region, the digestive system contends where more in line with a moderate climate. the explanation offered was that there could have been a shift in the earth angle of tilt. I believe that the time scale on this would have been in the neighborhood of 12000yrs ago. The effects of such a dramatic change would vary, some regions would move from moderate to cold, in other areas you would see the opposite change, from cold to warm.

    Such a change would have to be caused by gravitational interaction with a fairly massive body. 1200yrs seems a little late for such a interaction.
  6. Aug 7, 2008 #5
    Brian Fagan, the retired archeologist has produced a series of books on weather discerned from the archeologic record, including food and migration patterns. I believe his work about this time period should prove useful in answering some of the questions raised.
  7. Aug 7, 2008 #6


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  8. Aug 7, 2008 #7
    In Whitehorse, Yukon, Canada they have the Beringia Interpretive Centre which I went through a couple years ago. It has woolly mammoths and other animals on display. You can take a virtual tour etc here:

    http://www.beringia.com/01/01index.html [Broken]
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  9. Aug 8, 2008 #8
    You guys picked a wrong time to discuss mammoths. There are no "flash frozen" mammoths, just peat preserved mummies of mammoths including complete stomach contents. The Yukagir mammoth has been analysed in detail again with the same result: productive grassy steppe.
  10. Aug 8, 2008 #9

    jim mcnamara

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    The Younger Dryas manifests in the Chesapeake Bay region in the Eastern US as a ~.5 - 3m aeolian layer deposited over a period of ~800 years. It was very dry in that area with a lot of blown dust - obviously - during that time. The onset was abrupt, based on pollen analysis.

    One hypothesis for the cooler dryer phase was that the St Lawrence River became ice free, and really massive fresh water flows caused thermohaline flow shutdown.

    http://www.ldeo.columbia.edu/res/pi/arch/examples.shtml [Broken]
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  11. Aug 8, 2008 #10
    That hypothesis is not supported by any evidence: see

    http://cgrg.geog.uvic.ca/abstracts/LowellTestingMeltwater.html [Broken]

    It's also a bit unclear/counter intuitive how a relative (earth scale) minor hydrographic event could have such an impact allmost world wide, including oceanic proxies in the Pacific.
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  12. Aug 11, 2008 #11

    jim mcnamara

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    What you show is another hypothesis, clearly: Does this article constitute "any" evidence?

  13. Aug 12, 2008 #12
    Dunno, they sought supper for the melt water hypothesis but didn't find any:
    The EOS article:
    http://www.eeescience.utoledo.edu/Faculty/Fisher/Lowell_etal_EOS05.pdf [Broken]

    Currently no access to the article, but I would not take any conclusions before checking all the evidence and that's a few decades worth of work.

    See also:
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  14. Jan 24, 2009 #13
    The mammoths found preserved in standing positions with grasses and buttercups still in their mouths also had penile erections. The simple solution is that they were instantly suffocated by being engulfed in peat or soil and later frozen. An intense earthquake can cause liquefaction of the ground, and the weight of the mammoths would cause them to sink. The dating of the mammoths concerned is more in the order of 40,000 years ago.

    You are distorting the evidence to fit your own ideas, I believe.
  15. Jan 24, 2009 #14
    Better be very very careful with accusations like that :mad: . I actually participated a bit indirectly in the research around the Yugakir mammoth, discussed things directly with the men with hands on experience and provided plenty of supporting evidence for that. I also think it would be required to substantiate the flash freezing tale.

    See for instance this and this, with an elaborate abstract http://www.yukonmuseums.ca/mammoth/abstrmol-mor.htm [Broken].

    Also mind that these mummies had to survive the Holocene thermal optimum when Siberia was several degrees warmer than today.
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  16. Jan 27, 2009 #15
    I didn't intend to make you mad Andre. Let's have a logical level-headed debate about the issue. Professor of zoology at the University of Alaska, R. Dale Guthrie, who lives above 60'N has this to say about the preservation of intact whole bodies in freezing temperatures (see attachments):

    Taken from his book 'Frozen Fauna of the Mammoth Steppe: The Story of Blue Babe'.

    BTW I didn't take issue with the 'flash freezing' question, it was the way you dismiss the evidence of an unusual event. You said "just peat preserved mummies", but I disagree. This doesn't fit with the details given by Guthrie.

    Attached Files:

  17. Jan 27, 2009 #16
    Here are a few interesting pages from Guthrie's book. There are many more cases like this, including other large fauna such as the Selerikan Pony and the Churapachi Woolly Rhino. It's a fascinating read which I highly recommend if you are interested in this debate.

    Attached Files:

    Last edited: Jan 27, 2009
  18. Jan 27, 2009 #17


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    These statements still need some kind of reference to support them.
  19. Jan 28, 2009 #18
    My reference is the book 'Frozen Fauna of the Mammoth Steppe: The Story of Blue Babe' by R. Dale Guthrie, professor of zoology at the University of Alaska.

    Khatanga mammoth.
    Shandrin mammoth.
    Selerikan Pony.
    (found in an upright position similar to Berezovka mammoth)

    There is plenty more data given in the book. The evidence clearly suggests the potential for an unusual set of events.
  20. Jan 28, 2009 #19
    The only known 'complete' mummies are babies, blue babe, Dima and the recently found one:


    I believe that thermal inertia is related to the third power of the body size, so that's not comparable with adult versions, for instance the Jarkov and the Yukagir mammoths of which there are only parts mummified. The Yukagir only the head, part of the back, intestines and a foreleg. From the contents of the guts it is know that it died in springtime, so it had a complete summer to decompose. A mammoth head is mostly hollow with a sort of honeycomb construction and it contains relatively little soft tissues hence the chance of it's preservation is better than body parts.

    Also consider why most mummies are mammoths and not the equally abundant horses, bison, antilopes etc, if there was this sudden freezing, wouldn't those have an equal chance on mummification?

    As far as I know mammoth mummies are associated with near by water or remains of water fauna (Jarkov). So it could be speculated that it has to do with mummification as the cavities in the skull may fill up quickly after drowing, providing effetive cooling. The Yukagir head cavities are completely filled with mud.

    The fantastic tales of the older mammoth mummies in the nineteenth century cannot be duplicated and peer reviewed.

    Time is up, more to follow later.
  21. Jan 28, 2009 #20
    Do you have any links or references for these statements?

    There isn't enough cases for a statistical analysis, surely? BTW you keep referring to a "sudden freezing". It is also the nature of (sudden) complete burial of large fauna in their prime which is unusual, e.g the Selerikan stallion. This doesn't happen in real life, it is usually the yound or old which are unable to free themselves.

    It could also be speculated that the association with water locations is indicative of deep silty mud deposits. This would fit with the liquefaction due to earthquake idea. Also note that flowing mud is by definition above 0'C. It wouldn't provide effective cooling against decomposition.

    The professional research has been done by a professor of zoology around the 1980's.

    Interestingly Andre, you do seem to agree with Guthrie's Mammoth Steppe hypothesis (which I do myself). This is where Berengia is speculated to have supported a permanent population of large fauna due to a grassland habitat resulting from increased aridity. He also illustrates the extent of the North American icesheets. Do you disagree with this as well?
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