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Mammoths and climate sceptism

  1. Aug 28, 2009 #1
    It may be known that the roots of current climate concerns and alarmism are in the study of paleo climate, especially the last 'ice age' as documented extensively by Spencer Weart here.

    It seems that things all add up, especially ice core records and proxies as well as oceanic isotope proxies. However, new discoveries are made on a regular basis and a more close examination of the details is possible. For instance the north Siberian plains, once the biotope of the Woolly mammoth, is worth a close investigation.

    So what follows is a fragment of a manuscript I'm working on for discussion. It's that past that triggered my "independent" ideas, encouraged by several of the researchers in that area.

    Quoting from own concept. Note that this only describes the various publications, which should all be in this list. No theory devellopment whatsoever. It just intends to show that things do not add up nicely.


     
    Last edited: Aug 28, 2009
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  3. Aug 28, 2009 #2

    Ivan Seeking

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    So it is your intent to post "your concept" without a prior publications of that concept? Has your assertion that things "don't add up nicely" been published in an appropriate journal?

    In other words, do climate change experts consider this to be significant, or is this your conclusion or a conclusion found at blogs?
     
  4. Aug 28, 2009 #3
    maybe check the peer reviewed published references again. Nothing in the compilation is my conclusion.

    This one for instance is freely available with compilations of several others
     
    Last edited: Aug 28, 2009
  5. Aug 28, 2009 #4
    Another interesting case is the Fishhook mammoth, published in Mol et al 2006

    Interesting details are in this conference abstract (reflected in the publication)

    And that was the cold(est?) period in northernmost Siberia?
     
    Last edited: Aug 28, 2009
  6. Aug 29, 2009 #5
    Let's look at Hubberten et al 2004 again.

    We are interested in fig 6 page 1339 (7):

    2zoatc5.jpg

    with the caption:

    We see quite some variation in biotopes and apparent temperature regimes. The sudden spikes starting at 15,000 years are interesting. Would this be in synch with the greenland ice cores or?

    More later.
     
  7. Aug 29, 2009 #6
    So let's look at the oxygen isotope ratios of the ice in one of the Greenland ice cores (GRIP):

    11llnxs.jpg

    Source

    The isotope ratios (green graph) change during different processes in the water cycle, during evaporation, condensation and transportation ('raining out'). These changes are directly dependent on temperature, therefore it is inferred that the isotope ratios are a proxy for temperatures (for instance Jouzel et al 1997). With a quick glance on the black time scale on the left and comparing it with fig 6 of Hubberten et al 2004, it appears that -at 15,000years- the big spikes correlate closely. These spikes are known as the Bolling Allerod interstadial btw. So it is very well possible that this kind of comparisons may have convinced the researchers many years ago that things added up nicely indeed.

    There is a big problem though, we are comparing apples with oranges, and there are some issues with carbon dating that was unknown in the early days. Due to a rather large variation in 14C radiocarbon ratios in the atmosphere the carbon dating method has large irregularities. Ardious labor on this problem has produced a rather robust calibration table, latest version: INTCAL04, showing up to several thousand years of differences between carbon dating and counted dating, as the ice cores annual layers are counted.

    Therefore the carbon dates are added in red at the right side of the Y-axis using the calibration table. Now we see that the 15,000 carbon years of Hubberten et al, 2004 translates to some ~18,000 real counted or calendar year, hence the warming in Siberia appeared to have started well before the warming signal of the ice core isotope proxies on Greenland. Things seem not to add up so nicely at all.
     
    Last edited: Aug 29, 2009
  8. Aug 30, 2009 #7
    So it appears that we have a bit of a 'mystery' to solve for the period spanning roughly 14,500-17,500 years ago, when the interpretation of the isotopes in the ice cores suggest very 'cold' but the Mammoth steppe suggest "warmest Tundra Steppe" being warmer than today, at least in the summer, and warmer than the interval 48-24,000 carbon dated years ago.

    Now we have been here last year, when I posted a lot more evidence for that 'mystery':

    Now with the abundance of reports for warming of that 17.5k to 14.5 k 'mystery' - interval and the discrepancy between warming of the two hemispheres, as the southern hemisphere has similar warming timing, there may be enough reasons to revisit the interpretation of the isotopes of the greenland ice cores.

    I did that and I can demonstrate with normal physical- hydrographic knowledge, that other processes than warming and cooling can have similar effects on the isotope signatures of the Greenland isotopes. Those may be more consistent with all geologic and paleo-climatal records. This is not theory develloping, but merely the alternate application of existing knowledge. The question is, can I discuss this in these forums?
     
    Last edited: Aug 30, 2009
  9. Aug 30, 2009 #8

    lisab

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    I'll be disappointed with PF if the answer to that question is "no."

    I'm an adult, I can think for myself...hearing alternative interpretations of observations won't warp my (also very little :smile:) brain.
     
  10. Aug 30, 2009 #9
    Thanks for the support, Lisa

    I think it's legal to elaborate on the isotopic hydrographic processes and demonstrate what the consequences are of variations in parameters. But ultimately it all boils down to the sciencific method:

    1: Observing phenomona (variation in isotopes in the ice cores)

    2: Formulate a plausible construction to explain it (hypothesis): isotopes are temperature proxies. However such a hypothesis is always a choice out of several possiblities. It could be something else. Therefore:

    3: Make predictions based on those constructions

    4: test it. Now, the original tests with field observations may have been done against carbon dated records, which may have looked good. However the accurate calibration of carbon date became available later and the tests may never have been revisited.

    So the different studies on isotopes agree on temperature differences in the order of magnitude of ten degrees along those spikes. However the siberian mammoths and their reconstructed biotopes clearly refute such a temperature swing. On the contrary, where the isotopes are low, their biotopes are warmer than today. But also as seen the isotope spikes are not consistent with the other temperature indicators like the insect remains or glacial retreats. Hence with the current state of the science, it appears that some of the isotope variations have other causes than temperature.

    We could stop here, nothing in the next phase, right or wrong can undo these results. The scientific method now calls for a revision of the hypothesis. That's not to me to do, but I could indicate which processes in the hydrografic cycle may have similar effects to temperature swings.

    Obviously the implications of this evidence is rather extensive. First of all, there is a very tight correlation of methane greenhouse gas with these isotopes, see for instance Flueckiger et al 2004. But what if that is not directly related to temperature?

    Anyway I intend to start a new thread about the isotopes in the ice cores and the hydrographic cycle since it would drift too much off topic in this thread.
     
    Last edited: Aug 30, 2009
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