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Climate and Clathrate

  1. Sep 9, 2004 #1
    We have been fighting the last few days about the enormous impact of minute changes in a minute factor, carbon dioxide. We think that CO2 is causing significant more (triple to five times more) Greenhouse gas effect changes than it's fair share. We base this on the ice cores, the apparent greenhouse effect on the Planet Venus and the general correlation of the tendencies of carbon dioxide concentration and the apparant general temperature trend in the last centuries A.K.A. the highly disputed hockeystick. (Mann et al 98)

    But the word "Clathrate" is not in the ...err..Scientific basis of the IPCC.

    (BTW This is going to be rather complicated. So if you're not familiar with the terms and mechanisms you may need some time to study the links. That may be discouraging. However, it may help if you want to find out why I'm stubbornly denying catastrophic Antropogenic Global Warning -or not being qualified to do so- agree with the skeptics about Global Warming being an unfounded hype, as I'm intending to reveal in here why.)

    More specific, I'm intending in this thread to show (proof) that the alleged violent paleoclimate changes were in reality only isotope ratio changes due to changes in fractination processes, induced by Clathrate destabilisation events.

    Clathrate is ...

    This last remark of course is based on the assumed tremendous climatal sensitivity to changes in greenhouse gas concentrations. Also like this study assumes.

    Oops :eek: So far we seem to be heading to a conformation of global warming. I seem to be shooting in my foot.

    But more later.
    Last edited: Sep 9, 2004
  2. jcsd
  3. Sep 10, 2004 #2
    32 hits and 0 replies. Well, when I rant about the global warming hype I can stand to be corrected and everybody being there but when I explain why I rant, nobody's home. Anyway for those who are interested in Clathrate, Isotopes and (Paleo) Climate, perhaps have a close look at the latest devellopments on Greenlands Ice cores.

    Thanks to Nilequeen for finding this link

    Our main focal point linking to clathrate and climate are the "Dansgaard Oeschger" events, clearly visible in the Greenland ice cores.

    Also note the article -as usual- consist of two parts. Data and interpretation. Try and stick to data only. Interpretation is subject to bias and textbook consensus.

    The main objective is the investigation of the correlation of Dansgaard Oeschger events with possible clathrate events.
  4. Sep 11, 2004 #3
    Okay. So I've read the linked sites. I'm not positive I understand what you're proposing, though.

    Are you saying that clathrate (methane hydrate) events (sudden exposure and melting of large clathrate deposits) rapidly and heavily increased the methane concentration in the air, thus causing the oxygen isotope ratio to alter but NOT causing a supposed rise in temperature typically inferred from the change in oxygen isotopes?

    If no, then what are you proposing?

    If yes, then what is the mechanism by which higher methane concentrations would change the oxygen isotope ratio? (I'm not well versed in that area)

    On a lighter note:
  5. Sep 11, 2004 #4
    Well I have followed many of your other posts, that lead up to a agendy at hand. Are you postulating clathrate (methane hydrate) events are secondaring events to or the results of >>> http://www.homepage.montana.edu/~geol445/hyperglac/time1/milankov.htm
    or primary cause of which the cycles make a minor or little effect in glacial periods?
  6. Sep 11, 2004 #5
    Well, thanks for the feedback. I'm afraid that that it isn't going to be easy. Yes you can find plenty of links explaining ice ages and the general idea is that things are pretty much explained. But they aren't, not even faintly. For instance there are a lot of circular reasonings. For instance isotope ratios are sensitive to temperature. So isotope ratio change is temperature change. We have had ice ages and we see isotope changes so ice ages can be made visible by isotopes.
    But we should admit that we are in big trouble when large parts of the world were actually warmer during the last glacial maximum than they are today.

    If you have studied the carbon dating thread, I showed that in the early days, 14C isotopes were directly linked to a date assuming a constant 14C ratio in the CO2 in the air and a fixed ratio when the CO2 was converted to biomass. Both were utterly wrong.

    We still make the same mistakes with isotopes of the ice cores and sediment cores. Yes they are sensitive to temperature change but also to the original ratio of the source and to the processes that were involved before the ice and the sediments were formed.

    Isotopes are only representing temperature if you know exactly what the source isotope ratio was and if you know the processes.

    Now, the ice age theory is from about 1834 (Louis Agassiz) but with much not accounted for. When Imbrie and Imbrie cheered that they had solved the Ice Age riddle with by "proving" Croll-Milankovitch, they had never heard of clathrate because it was not discovered yet. But the global warming is based on this ice age solution and any change in isotope ratios is considered temperature now.

    This makes the Dansgaard Oeschger events very interesting because they seem to be defeating physical laws. About all isotopes wiggle violently, especially in Europe, yet we have near continuous in situ paleonthologic records indicating little or no climate change in the 60-28,000 years range in Europe, let alone those violent oscilations of climate. Here is a very comprehensive study of those oscilations but without any clathrate.

    Here is where the Clathrate comes in and things get pretty interesting. The ice age story is totally different.

    More about that next time.
    Last edited: Sep 11, 2004
  7. Sep 12, 2004 #6
    Let's focus on that link about the "clathrate gun". You need a free subscription to open that link. You can register here under the third "proceed" button.

    Anyway, the abstract.

    Check especially figure 2. (Opens only when registered.)

    "Interstadials" are Dansgaard Oeschger events.

    Before the clathrate gun, the interstadials were linked to the Thermal Haline Current (THC) a.k.a. gulfstream. So there has been quite a dispute about the validity of the clathrate hypothesis. It was thought that the Clathrate gun is firing blanks but we could refute that if required.

    The latest devellopments seems to be that the clathrate gun is about to shoot the opposition. The same author poses here (scroll down 1/3) that continental slope failures that induce massive clathrate release coincide with Heinrich events, the Bolling Allerod event (the big spike is the greenland ice cores between 15,5 and 13,5 K years) and the onset of the holocene. Not the interstadials (D-O events) but Kennett had another mechanism for that.

    But everybody links clathrate events to climate change (warming) due to the change in isotopes. I attempt to show that the isotope changes were an immediate result of the clathrate events without needing warming.
  8. Sep 13, 2004 #7
    Well, it's getting awfully quiet here. So how deep do you want to dig before understanding what the ice core are telling us and what lie we like to believe in (getting bold now - seeking discussion). Anyway, we have just started yet and we need to know all there is, right now before we can speculate a bit on the role of clathrate on the isotopes.

    Today I'd like to leave the clathrate were it is right now, and focus a bit on isotope behavior in the precipitation cycle in relation to temperature and the problems that have been identified already in that area, especially during the "Last Glacial Maximum" in the Greenland ice cores.

    This is the "piece the resistance", but also without any clathrate.

    But is it useful to continue or am I talking to an empty class? :eek:
  9. Sep 13, 2004 #8
    Ahem. Your "class" wants you to publish your ideas...
  10. Sep 13, 2004 #9
    Last edited: Sep 13, 2004
  11. Sep 14, 2004 #10
    I'm reading Andre. I haven't seen a reason to reply because I feel like the end of each of your posts as an explicit or implicit "to be continued..."

    And so I check back later :smile:
  12. Sep 14, 2004 #11
    Ok, I’ll continue and publish.

    Let's see what the current understanding is of stabile isotopes in the precipitation cycle. Of course science is a lot further than "isotopes-is-temperatures" as I bluntly stated earlier; several complications have been recognized, but perhaps not all.

    The fundamental factors that determine the isotope ratio of water isotopes at the destination ice cores are:
    - temperature, relative humidity and wind speed at the source of evaporation,
    - temperature and absolute humidity at the area of condensation, or sublimation if the vapor changes directly into ice.

    Furthermore, there are rain out effects, amount effects, Oreo graphical effects, re-¬evaporation effects and kinematical processes.

    Both heavy oxygen ratio d180 and heavy hydrogen (Deuterium) ratio (dD) react a bit or even a lot differently in these fractionation processes. It has been empirically established that fractionation of deuterium is mostly dependent on the source temperature and heavy oxygen reacts more strongly during condensation. So it is generally assumed that d180 is giving the local temperature whilst the so-called Deuterium Excess (defined as d = d180 - 8*dD ....Dansgaard 1966) tells something about the temperature of the evaporation source.

    So, explorers concentrate on these basics and get one surprise after the other (understated by: not completely understood). The Greenland temperature characteristix during the last glacial maximum are dramatically out of line compared with general data. This is
    attributed to a change of main snow fall season. (Jouzel et al QSR 2000). Furthermore it appears that the isotopes of the low latitude (tropical) glaciers of the Andes are virtually insensitive to temperature changes but instead; fluctuate in correlation with the amount of precipitation (Hoffman et al GRL 2003).

    Moreover, the new EPICA Dome C records (Stenni et aI, EPSL 2003) reveal that this site has cooled between 41,000 and 28,000 years ago but simultaneously, the average sea surface temperature is assumed to have warmed in that same time frame, when using the "Deuterium Excess"-method. So, it seems that we are looking at a totally different world during the ice ages with totally different climate laws and every anomaly is given an individual explanation if any. Or could there be other explanations?

    Incidentally, the Little Ice Age of the sixteenth century shows very distinctly in the Greenland Ice Cores (GRIP - Jouzel et aI1998). The dip in the Deuterium Excess suggests that the North Atlantic sea surface temperatures have been well below normal. However, the global warmers managed to kill the Little Ice Age (MBH98).

    The Andes response makes you wonder about the correlation of the (Ant)-Arctic ice cores and amount of precipitation. And surprise: a near perfect match of each and every individual isotope spike in the Vostok core (Andre et al 2002 :wink: ):

    (fragment of Vostok dD (red) versus snow layer thickness (blue) between 200,000 and 350,000 years ago)

    To date I have not seen any remarks, let alone an explanation, accounting for this match. Especially the dramatic increase in snowfall at the onset of the alleged interglacials. Of course, when it is warmer (as in less freezing), there can be more snowfall but that is not necessarily so. And on the other hand you can use evidence only once. Some part of the isotope ratio evidence is temperature, but some other part is caused by variations in amounts of water vapor or absolute humidity, rain out effects etc and perhaps even a lot more than is accounted for as suggested by the high correlation between dD and annual ice layer thickness. This would imply that the temperature difference, associated with glacial and interglacial periods, is not nearly as large as suggested.

    Wait a minute, I hear you say. How about the borehole temperatures known from the Greenland Ice cores? How about the actual temperatures that were taken in the boreholes of the ice cores? Aren't those representing actual temperatures of the ice ages and the interglacials?

    I think not. During the Last Glacial Maximum there was very little snowfall both summer and winter and this would suggest that there was enough time during the yearly season to even out the temperature of the top layers of the snow. Hence, the borehole temperatures reflect pretty much the average yearly temperature in this period. Now, during the Holocene -after the ice age- the snowfall increased dramatically up until five fold the LGM values. So thick insulating snow layer was build every year, trapping the temperature during the actual snowfall period and temperatures may not have evened out completely during the remainder of the yearly cycle. So, the borehole temperature may be biased towards the temperature of the snowfall season, which is obviously not wintertime, when it is too cold to snow.

    So the average temperatures during the Holocene and the interglacials could still be a lot lower than we assume. And certainly, if true, this should be seriously affecting the alleged scientific basis of global warming.

    I should stop here after having thrown that bomb. Back with Clathrate soon.

    QSR: Quaternary Science Review
    GRL: Geophysical Research Letters
    EPSL Earth and Planetary Science Letters
    Last edited: Sep 14, 2004
  13. Sep 30, 2004 #12
    I'm still interested, and I don't think I'm the only one.
    We're just listening, that's all.
  14. Oct 1, 2004 #13
    Okay, I had a post ready of several pages but lost it due to an 404 followed by a crash all of a sudden. The bigger problem (by experience) is trying to explain how we could have used response characteristics of lineair open loop systems to determine, which signal could be input and which signal could be output, more than comparing time scales with their errors. This is giving some remarkable results.

    Back soon on this.
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