Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Paleao Glacial Confusion

  1. Apr 26, 2005 #1
    In another thread there is a rant going on about the thrustworthiness of the experts about global warming. Let's investigate one of those unrefuted pillars, the ice age, to be more precieze, the termination of the last glaciation and the Younger Dryas.

    Then what is the Younger Dryas?

    The discovery of the younger dryas in the GISP ice cores of Greenland was a major contributor to the global warming notion.

    I intend to show in a fallacy free way just by combining other peer reviewed information -not even making conclusions - just showing the evidence- that the Younger Dryas was something completely different despite this broad general consensus and that it has nothing to do with global warming - greenhouse effect.
     
  2. jcsd
  3. Apr 26, 2005 #2
    Here is the first little crack that happened to trigger a chain reaction:

    Now what to do with this rebellion? See it as a local anomaly and continue business as usual? or do a little survey about:

     
  4. Apr 26, 2005 #3
    I guess it's useless you people want to be mislead,

    [deleting physicsforums from "favorites"]

    Good bye
     
  5. Apr 26, 2005 #4
    I hope you don't leave the forums. Different points of view are important. I enjoy reading new lines of thought and studies.
    New research is always hard to impress on people. Please don't take it personally, that people don't embrace it.
     
  6. Apr 26, 2005 #5

    matthyaouw

    User Avatar
    Gold Member

    I agree with hypatia. I enjoy reading your contributions to the forum.
     
  7. May 2, 2005 #6
    Okay, It may be still pointless then but then again, at least I know I have tried and stop the mammoth tanker of the global warming political demagogic campaign.

    Again, lets return to the younger dryas. The first person here: http://www.npr.org/templates/story/story.php?storyId=1893089 shows why the ice cores heavily fueled the global warming hype. This is his explanation.

    You see: Younger Dryas is a return to glacial conditions. Moreover the methane (CH4) concentration closely follows the "temperature" proxie, that is actually isotopes with a very crude addition of borehole temperatures. So it basically boils down to: methane is greenhouse gas, greenhouse gas is causing climate change (hence global warming). Bingo crusade again greenhouse gas emission.

    We shall tear down the myth of the extreme Younger Dryas temperature changes in the next posts, using as tool:

    Hughen, K.A., J.T. Overpeck, S.J. Lehman, M. Kashgarian, L.C. Peterson, and R. Alley. 1998. Deglacial 14C calibration, activity and climate from a marine varve record. Nature 391: 65-68.

    See the last author? The same. So he could have known.

    and remember:
    "Non calor, sed umor".
     
    Last edited: May 2, 2005
  8. May 2, 2005 #7

    matthyaouw

    User Avatar
    Gold Member

    I'm glad you are back.

    I'm slowly sifting through all these sources, though some seem a bit complex to me. One thing in particular stood out as I read it:

    from- http://encyclopedia.lockergnome.com/s/b/Younger_Dryas

    Now this doesn't seem to add up to me... The impression I'd always got from current climate change theory was that it was a gradual process, and even though any human intervention was drastically speeding this up, the change was still at a mere fraction of the rate suggested above...
    I'm not sure I understand.
     
  9. May 3, 2005 #8
    Exactly, it doesn't add up and if that's the case, there is a fair chance that the interpretation of the evidence is wrong. Then it's time to start thinking out of the box, as discussed in this thread, which means back to the evidence, skip the conclusions (like temperature changes). Investigate ALL available evidence, not only ice cores or ocean floor cores.

    That brings us to the carbon dating platform problems first.

    more later
     
  10. May 3, 2005 #9
    In this thread we have discussed the problems (and solutions) of Carbon Dating. Especialy this part is essential:

    Now recheck my second post and notice that this abstract uses both original carbon BP dates as well as the calibrated dates to calendar years "between 17,000 and ~15,000 14C yr BP (~20,000-18,000 cal yr B.P."

    However when you read abstracts it turns out that this is quite uncommon. Several branches in earth science are not modern enough to convert "BP" to "Cal BP". Given the large range of calibration differences compared to the short duration of the Younger Dryas you may talk about completely different timing. That gave me the idea to "audit" several older and modern publications that talked about unusual glacial readvances at the end of the last ice age to see if the calibrated dating of those readvances would coincide with the calibrated dating of the Younger Dryas.

    Guess what.
     
  11. May 3, 2005 #10

    Monique

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    I don't quite follow the following:
    How does it follows from the above arguments that it is a crusade against greenhouse gas emission?
    So are you suggesting that there were no extreme temperature changes during the Younger Dryas?
     
  12. May 3, 2005 #11
    Thanks for the feedback Monique

    Richard Alley will explain:

    Note: that point being the end of the Younger Dryas with an alleged warming of some 10 degrees far more than can be attributed to pure basic greenhouse gas effect of some 0,7 degrees per doubling of CO2. So at this point the positive feedback factors were invented that would allegedly make the climate very unstable. But that's off topic at the moment.

    Indeed, I know that this is one of the most basic paradigms of palaeo climate. Nevertheless, it's the intention here of combining the data of all proxies to show - proof- explain the fundamentals of: "non calor sed umor"
     
  13. May 3, 2005 #12
    Here is our working sheet. Advise to view on 1:1 size. The year scale on the Y axis the upper right site is carbon years BP while the X-axis is Calender years BP. The line of numerous open and closed dots triangles and diamonds are calibration points of several proxies. The annual layers of trees (dendrochronology), lake sediments (varves) etc are both counted and carbon dated and the results are shown. Note that the several proxies are in good agreement. To the bottom I computed the annual precipitiation in the Greenland ice cores (Alley et 2004). Note the boundaries of the Younger Dryas shrink considerably on the y-axis of the carbon dating, roughly from 10,100 to 10,600 14C years BP.

    The next idea is to google up all papers with carbon dated glacial readvances in those periods and plot them in on the Y-axis on the BP scale and converting them to the Cal BP scale and see how many fall in the Younger Dryas period.

    Questions so far? Do I get help? I found some 25 papers so far.
     
  14. May 3, 2005 #13
    The first I heard of this was in 1995, and I half to admit I was sceptical. But by 2001 I was convinced that a highly variable climate system was indeed viable.
    Things like tree rings and Ice/bog cores don't lie.
     
    Last edited: May 3, 2005
  15. May 4, 2005 #14
    Right, and after this, one tends to philosophize about the scientific method like somewhere else in these forums. Anyway, I jotted down the dating results
    here

    Again, strongly advise to view it on a 1:1 scale.

    The numbers are according the ref list below. Whenever a BP date was given it's on the upper right scale. Sometimes Cal BP dates were given and put in in the middle x-axes. Scroll down to the bottom to see all dates converted to calender years. We see numerous glacial advances outside the Younger Dryas (blue), several with ambigeous datings, crossing borders between the BA - YD and BP (violet) and only an odd glacial readvance within the Younger Drays. I know the method is not perfect but what does that say about this?:

    I don't think so. Maximum Palaeo Glacial Confusion.

    The refs (I'll elaborate whenever challenged):
    Note the correlation between glacial readvances and precipitation rates in the Greenland Ice core GISPII. In other words "Non calor sed umor".
     
    Last edited: May 4, 2005
  16. May 6, 2005 #15
    Now let me try to explain what I tried to explain in this thread:

    The current paradigm is that the Younger Dryas was a brief period of intense cold accompagnied by massive glacial readvance. But we are well underway to show that this is a very spurious idea of the Younger Dryas. Instead it was a dry event with no reason to assume that the period was colder than either the previous Bolling Allerod "interstadial" or the following Pre Boreal period.

    We have shown that the vast majority of (global) glacier readvance actually occured outside the Younger Dryas with peaks just prior and after this event.

    The reason of the widespread misconception is probably related to the problems with carbon dating. Early pollen records showed an explosion of the tundra flower Dryas octopetala pollen that could be dated between 10,000 and 11,000 BP (carbon years), moreover the total number of pollen was highly decreased in this period. Next, there were many glacier readvances datable "between" 10,000 and 11,000 carbon years "within the Younger Dryas" (but actually AT both 10,000 BP and 11,000 BP - not in between and consequently outside the Younger Dryas). So from this, the hypothesis of the cold Younger Dryas with glacier readvances was formulated and later that hypothesis was "confirmed" by the stable isotope (d18O, dD) behavior of the Greenland ice cores GRIP and GISP2. On the other hand, the cold "Younger Dryas" confirmed that the isotope behavior was temperature related. So due to this beautiful circular reasoning - begging the question, the cold Younger Dryas is now one of the most deeply rooted errors in paleao climate.

    The problems related to carbon dating are the highly variable delta 14C around the end of the Pleistocene. This caused a distinct "carbon dating platform" or a relatively small change in carbon dating was in reality a large change in actual calendar dating. So the only thing what we did is calibrating all known glacier readvance carbon dates to real calendar dates. The result is that almost all readvances occured outside the Younger Dryas in the alleged "warm" Bolling Allerod and Holocene. Also the massive glacial retreats are dated around 17-13,000 carbon years or between 21 and 15,000 calendar years ago, well before the alleged warm Bolling Allerod. The interruption of the glacial retreat and some glacier readvance happened shortly after 13000 carbon years or 15,000 real years ago or at the onset of the alleged warm Bolling Allerod. So if the slight warming of nowadays (~0,6C) causes large scale glacial retreat then how can the distinct warming of the Bolling Allerod (5-7C) cause a glacial readvance?

    It can be concluded that the Bolling-Allerod event as well as the onset of the Holocene (Pre Boreal) were not warm at all. It was very wet instead and furthermore that the Younger Dryas was a dry event, not necesarely colder, hence: non calor sed umor.

    Another consequence is that the stable isotope behavior in the ice cores are not primarily temperature related but moisture related. But this error is the base of the global warming idea, assuming an unstable global climate with large positive feedback factors, causing a strongly increased greenhouse gas effect after a small increase of CO2 in the atmosphere. This was ultimately the reason for some people to crusade against global warming. Too bad. So, sloppy science without correcting for the well known carbon dating error is going to cost the world dearly by aiming the corrective measures to the wrong cause.
     
    Last edited: May 6, 2005
  17. May 7, 2005 #16
    So that all basically implies that the current understanding of the ice age can be trashed and this is normal, not exception:

    Emphasis mine

    Remember that thats exactly the same area with the claim:

    Good for the trashcan from the onset. That's what happens when you specialize and fixate on one item only.
     
  18. Jun 19, 2005 #17
    according to your rapid polar wander theory, ice ages did not happen. hence net volume of ice on earth does not vary significantly through time.however how would you then explain the large variations in sea level that were experianced throughout the holoscene epoch?
     
  19. Jun 20, 2005 #18
    Hi Sage,

    Consider this, there is an ice age hypothesis with waxing and waning ice sheets. This requires an sea level yoyo. So we go to Barbados, (nice place) and investigate. And what do you know, the sealevel behaves nicely according to that yoyo. So we try other places, and then some nasty things happen. We sea all around the South Chinese sea holocene sea level lowering hapening. The same around St-America and regarding Beijing, that was also sea bottom less than 80,000 years ago (Wuchang Wei 2002). Fortunately, Australia is behaving nicely again. So if you read publications about the sea level behavior and ice ages, plot the areas that are refered to. You will see that it concentrates in two areas, the Carribean and Australia / Indonesia

    So we appeared to have a problem for a moment but we have two places now that sustain the sea level yoyo. So we write that triumphantely in the IPCC reports, a sea level rise of 126 meters murmering something about some local regions that abbarate due to local tectonic conditions. However 5 cm/year in the beginning of the Holocene for the South Chinese sea is way over the estimated maximum (15mm) tectonic uplift rate.

    So, you see that the sea level change idea is much more complicated. And of course, the Canadian Laurentide and European Weicheselian ice sheets did disappear after the Last Glacial Maximum and would have been good for some 50 meters of sea level rise. For that 126 meters we would have needed a considerable Siberian ice sheet, but any ice in Siberia melted 60,000 years ago already, long before the Last Glacial Maximum.

    All in all, the erratic sea level changes seem to have more to do with tectonics and guess what caused all those severe tectonic movements concentrated around the Pleistocene-Holocene boundary?
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?