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Paleocene Eocene Thermal Maximum: filling an ocean?

  1. Dec 17, 2006 #1
  2. jcsd
  3. Dec 17, 2006 #2
    These recent studies show some imposibilities which appear to be the key to the solution of the problem. How do you get fresh water duckweed and tropical algea into the arctic?
     
  4. Dec 17, 2006 #3
    So what are the main features of the PETM apart from the tropical algea and duckweed at the North Pole?

    The main evidence is indeed in the oceans. Gigantic isotope jumps in the proxies, a red clay layer in the oceans named Elmo, etc. etc.

    One of the most remarkable features of the PETM is its uniqueness. Nothing but really nothing in the geologic history resembles it at all. Given that, it appears evident that recurring events llike alleged greenhouse - ice house state changes on Earth would not suffice to explain it. That's why the greenhouse hype explanation is gibberish. Why is there only one PETM? Why not several at each high CO2 spike in the last so many 100 millions years ago? Actually the atmospheric CO2 was quite low already around the PETM.

    No, to explain a unique feature you require unique causes.

    One unique feature on geologic time scales is the continental drift due to plate tectonics. The topography of Earth is always unique as the continents drift around seemingly at random.

    Would that help?
     
    Last edited: Dec 17, 2006
  5. Dec 17, 2006 #4
    Not at all, since continental drift is not random, and takes place over millions of years, not thousands.
     
  6. Dec 17, 2006 #5
    Okay I ment to say that a certain location of the continents is unique in the time. Next year the world map is wrong, some continents have moved a quarter of an inch or something.

    An impression of the plate tectonics is animated here (source wikipedia) and each snapshot is unique.

    Meaning that somewhere in a unique setting of the continents something unique has happened.
     
  7. Dec 17, 2006 #6
    Last edited: Dec 17, 2006
  8. Dec 18, 2006 #7
    Nobody? Can't say that I did not give it a chance, Not interesting? Ridiculous? No idea what's up?

    Anyway, here is the abstract of the paper I'm working on, prio 2, the Mammoths go first:


    That's how you get tropical algae at the North Pole
     
    Last edited: Dec 18, 2006
  9. Dec 18, 2006 #8
    Now you could think that this is nonsense, however:

    Ernst SR , E Guasti, C Dupuis, RP Speijer 2006 Environmental perturbation in the southern Tethys across the Paleocene/Eocene boundary (Dababiya, Egypt): Foraminiferal and clay mineral records Marine Micropaleontology Volume 60, Issue 1 , 27 June 2006, Pages 89-111

     
  10. Dec 28, 2006 #9
    #Interesting, haven't had the time to look into all your refernces, but agree about the continent positions. Not sure but I think some major ocean stuff might have been going on.

    Go back to the mid Eocene and I think it is thought that a passage was open between north and south america, there is also some recent evidence that suggests an ice age at this time. Now I don't know all the evidence but presumably if (as someone I know who is just about to publish this suggests) this passage opened up in the Mid-Eocene, it would have been closed in the Early Eocene.

    This would have encouraged western boundary currents (similar to the Gulf Stream) to form, which would have carried more warmth to the poles and helped melt the ice caps. I definitely think the position of the continents was important.

    However I do not believe that any of this impedes on the validity of the greenhouse gases as a mechanism for global warming (take a look at Venus if you wann see what greenhouse gases can really do). Coupled with the fact that there is no evidence to suggest that the present-day continent arrangement is any less/more conducive to global warming than it was in the early eocene, I remain sceptical about those that use this kind of research to justify their climate/political views.
     
  11. Dec 29, 2006 #10
    Take a look at Mars, with blackbody temperature about the same as the actual temperature, to see what greenhouse gasses fail to do. However the case of Venus is probably utterly, completely different, when looking at all its features simulanously.

    Have a look here:

    http://www.bautforum.com/showthread.php?t=10879

    You realise that you are insulting me and disdaining the scientific process for a bunch of fallacies. Here are observations, ideas to explain them and evidence to support that. What on earth has that to do with climate/political views?
     
  12. Dec 29, 2006 #11
    I'm not trying to insult you. But if you're using your research to convince people that greenhouse gases aren't important then you're clearly politically motivated. The two mechanisms are not mutually exclusive.

    Your research is important but it is not as far reaching as you'd like to think, it certainly does not show that greenhouse gases are not important in raising global temps. In fact you insult me by suggesting that my ideas are "hype" and a bunch of scientific "fallacies". Perhaps you should be a little less sensationalist with your work, and try not to jump to such provokative and thoughtless conclusions.
     
  13. Dec 29, 2006 #12
    Right there, you're doing it again. Most definitely not. Being indifferent towards global warming, my research started off with investigating the mass murder on the Mammoths in 1999 with the sole objective to find out whodunnit.

    We solved that: here

    but in the process we also found out that the very basis of AGW, the interpretation of the ice cores and other isotope proxies got refuted in the process. I'll post that eventually. You may want to know that my first thought was: "oops this is terrible" but noticing the remorseless hatred campaign against anybody who had the guts to challenge anything, my sentiment has reversed 180 degrees.
     
    Last edited: Dec 29, 2006
  14. Dec 29, 2006 #13
    Andre, I am interested in what you have to say, but I am not sure exactly what it is that you are saying. I've clicked around as much as can be expected of any ordinary person, in an attempt to see what it is you are arguing. Perhaps it is time to sum up briefly your lines of evidence, and then clearly state your conclusions in one concise post.

    I have some issues with what I think you're saying but I need further clarification before I will comment.

    Cheers
     
  15. Dec 31, 2006 #14
  16. Jan 1, 2007 #15
    Unfortunately I can't currently read pdfs on this computer :(

    I guess the obvious point is why do you think the presence of duckweed and tropical algae in the Arctic is a nail in the coffin for the theory of greenhouse gas induced global warming??
     
  17. Jan 2, 2007 #16
  18. Jan 2, 2007 #17
    Perhaps if you could answer me more directly this would be a more interesting thread? It's nice to communicate with people and the references you give are great but they are no substitute for genuine discussion.

    Remember: I am not a researcher in this field, I don't have the time to try to draw out all the information for myself. But as a student of geophysics I am interested, especially with your claim that greenhouse gases are not significant in global warming.

    But I am confused because in one of the abstracts you cited earlier you mentioned how gas hydrates released beneath the frozen soil woulg have warmed the earth - these are greenhouse gases... See what I mean about not understanding your argument?
     
  19. Jan 3, 2007 #18
    Okay, there are many common features in terms of isotopes between the PETM 55 My and the Late Pleistocene. However the main difference is that the PETM happened only once, while the interglacials occur about every 100ky. On the latter we have orders of magnitude more data, yet it's very contradictory. My research however reveals that bluntly against the broad but sloppy consensus, there is very little if any evidnece that the isotope spikes in general are indicating temperature changes as in coming in and out of glacial periods.

    Thus isotopes are very lousy paleothermometers, simply because manu more events can cause isotope jumps, especially seasonality of precipitation. But isotope evidence is widely used to identify the PETM as cold warm.

    there is pretty strong evidence that the PETM is about massive release of oceanic methane hydrate, but what caused it? Warmth? Then the effect was aso GHG heating. Isn't there a whee bit circular reasoning in that. Chickens and eggs.

    How about massive methane hydrate release caused by a sudden dramatic eustatic sea level fall, reducing the pressure on the hydrate, causing it to destabilize on a global scale? How do you do that? By filling the empty Arctic bassin? The isotope spikes associated with it are merely reactions on precipitation patterns, acidity changes, salinity changes, and other chemical interactions, not drectly related to warmth.

    Have to think out of the box a little.
     
  20. Jan 3, 2007 #19
    I consider that it is more likely that a meteorite impact caused the catastrophic release of methane leading to the thermal maximum, it just seems more likely, but there could be any number of mechanisms. Sea level rises could have flooded a lot of the biosphere causing it to rot and release gases?

    Besides, this might be a unique event in our incomplete record (which has worse and worse resolution the further you go back in time), but it does not contradict anything I've heard about anthropogenic CO2 causing global warming. Our activity could be a trigger mechanism, no? Of course this hasn't happened before but that doesn't tell us anything because we haven't had industrial societies before.
     
  21. Jan 4, 2007 #20
    But we have had hundreds of large meteorite impacts in the last 4,7 Ga of which a few dozens are recognized in the last 600Ma. Some may have left distinct effects. There is the antipode flood basalt volcanism hypothesis. This may have occured with the K-T extinctintion, the Indian Deccan traps being antipode to the Chicxulub crater at 65 Ma. But, why wasn't there a catastrophic release of methane.

    Possebly the same happened during the End Permian extinctions and the Siberian Trap flood basalt volcanism and possible impacts http://researchnews.osu.edu/archive/erthboom.htm

    Hence not very unique

    A rather big difference with this type of events is the subsequent extinctions. Instead, the PETM led to an explosion of biodiversity.

    Another thing, after installing acrobat reader and reading my PDF file it should be clear that during the last glacial transition the large methane spikes did not lead to significant warming events, consequently there is no reason to expect something different then.
     
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