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Climate change: the future.

  1. Jul 13, 2007 #1
    Oh no, not another global warming thread!!! :surprised

    But seriously, I read that CO2 accounts for ~20% of the greenhouse effect on Earth, we are undoubtedly raising the amount of this (and other) greenhouse gases in the atmosphere. The greenhouse effect is very important in determining the lower atmosphere temperature, right? So isn't it a logical conclusion to draw that by increasing CO2 we will increase the greenhouse effect, and thereby increase the temperature of the lower atmosphere?

    I put it to you that global warming is not a "myth", (I don't care if someone misinterpreted past records, I'm looking forward now,) the greenhouse effect is real and it is contributing to (if not driving) global warming. Right?
     
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  3. Jul 16, 2007 #2

    Mk

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    That sounds good to me. It's worth mentioning that feedback (±, none) is a question, and about the logarithmic relationship between warming ability and concentration.

    I'm pretty sure the biggest issue is that if the world should be in crisis or not, and what we should do about it if we should.
     
  4. Jul 16, 2007 #3

    jambaugh

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    The issue is not so simple as CO2 is green house gas so more CO2 means more warming in proportion.

    Specifically the absorption lines of CO2 are at saturation i.e. already opaque in the principle bands. Thus increasing levels won't affect absorption further at those frequencies. So that 20% is mostly at saturation level and can't be increased by increasing concentrations. Rather there are two other issues. The absorption bands are roughly Gaussian in shape for short distance absorption and so increasing concentrations will only widen the absorption bands. This is a much smaller effect. The only prediction based directly on empirical data is that doubling the current CO2 concentration will at best induce a 0.012deg C increase in average global temp.

    See: http://www.john-daly.com/artifact.htm
    EDIT: (The above is a non-peer reviewed and somewhat controversial web posting. However there is included a zip-file of e-mail discussion and critique which is instructive.)

    The current computer models utilize historical correlations between CO2 levels and global temperature. It fails to differentiate between temperature induced CO2 increases, coincidence (since we are industrializing over a period of time where we are coming out of a recent cool spell) and actual CO2 induced warming. There are many modeling results published but this plurality of models are still based on a small set of actual driving factor calculations based on these "questionable" correlations.

    EDIT: (My statement above is not substantiated and too strong. I will do some more reading starting with the main IPCC citation: Cess et Al 1993 and either retract or qualify. This may take some time.)


    What we do know is the dramatic negative social and economic impact of the stringent emissions curtailing restrictions such as those proposed in Kyoto. People die just as dead from economic catastrophes as from environmental ones. So much better empirically based data confirming anthropogenic global warming, and an appropriate cost benefit analysis for utilization of (or restriction of) resources for CO2 reduction vs adaptation to climate change.

    The jury is still out and we should look (dispassionately) before we leap.
     
    Last edited: Jul 17, 2007
  5. Jul 17, 2007 #4

    Ivan Seeking

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  6. Jul 17, 2007 #5

    Ivan Seeking

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    The source site looks to be crackpot

    http://www.john-daly.com/dalybio.htm

    So we appear to have an unpublished paper from a site that claims to be biased. Unless you can show that this work is peer reviewed, it is not a valid reference.
     
  7. Jul 17, 2007 #6

    Ivan Seeking

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    According to the definitive source on this matter - the IPCC:

    http://ipcc-wg1.ucar.edu/wg1/Report/AR4WG1_Pub_SPM-v2.pdf
     
    Last edited: Jul 17, 2007
  8. Jul 17, 2007 #7

    Mk

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    Did your three posts thoughtfully criticize his facts yet?
     
  9. Jul 17, 2007 #8

    Integral

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    MK,
    It has been acknowledged that the mentor staff of PF does not have qualified earth scientists, to guarantee quality discussions we must INSIST upon peer reviewed references. If that article has not been published in a peer reviewed journal then we cannot accept it as a valid resource.

    Sorry if this bothers you.
     
  10. Jul 17, 2007 #9

    jambaugh

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    I got too bold, forgetting I'm here and not on usenet. I inserted some qualifying edits to my first post.
    ___________
    My apologies,
    James Baugh
     
  11. Jul 17, 2007 #10

    Attached Files:

  12. Jul 17, 2007 #11

    mheslep

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    Why must the IPCC be considered 'definitive'? It may be 'persuasive', 'informed', 'well sourced', etc. but who says its definitive.
     
  13. Jul 17, 2007 #12

    Evo

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    The IPCC document is a "work in progress" with many corrections already made to wrong information, new information disproving claims, etc...

    One of the head scientists for the IPCC resigned citing politics as obscuring the facts.

    http://sciencepolicy.colorado.edu/p...olicy_general/000318chris_landsea_leaves.html

    Another top climate scientist resigns.

    http://sciencepolicy.colorado.edu/ogmius/archives/issue_17/center_news.html

    I'm headed for bed, so don't have time to list all of Pielke's work, but this will show he is a well known authority and his work on climate science is published in peer reviewed journals.

    http://www.sciencemag.org/cgi/content/summary/310/5754/1625

    While we prefer links to peer reviewed sources, it is not mandatory here. As was pointed out, no mentor here has the expertise to say one way or another what is correct, so we would prefer to keep the links confined to recognized experts in the field. Links to obviously crank sites will be deleted.
     
    Last edited: Jul 17, 2007
  14. Jul 20, 2007 #13

    mheslep

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    The question is which data variable is causal. Take a close look; the C02 gradient lags the temperature gradient. Then, is C02 feedback to temp present?
     
    Last edited: Jul 20, 2007
  15. Jul 21, 2007 #14
    Perhaps you're right there, looking at the graph again, I notice that time is going backwards in the positive x-direction, so with this in mind there does appear to be a slight CO2 lag behind the temp. From that then, it is unclear what the relationship between CO2 and climate on Earth has been; if anything one might infer that temp has driven CO2 to rise. Other records have been similarly unequivocal.

    However, the past records are flawed in one very important regard: there was been no globally industrialized civilization to leave its mark. How limiting then are past records where CO2 has been allowed to vary naturally? It seems to me, much wiser to revert to first principles.
     
    Last edited: Jul 21, 2007
  16. Jul 21, 2007 #15
    Daly is using old science. RealClimate has a very clear explanation. http://www.realclimate.org/index.php/archives/2007/06/a-saturated-gassy-argument/#more-455
     
  17. Jul 21, 2007 #16

    Evo

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    Just a caution, www.realclimate.org is a blog and is non-peer reviewed. Blog posts can be considered opinion only.
     
    Last edited: Jul 21, 2007
  18. Jul 21, 2007 #17

    Of course. RealClimate is a climate scientists' public sevice, not a peer reviewed publication. It should certainly be an acceptable source for an explanation of CO2 atmospheric effects.


    "The creation of RealClimate was noticed by both the prestigious academic journals Science and Nature.[2][3]

    In 2005, the editors of Scientific American recognized RealClimate with a Science and Technology Web Award, writing:[4]

    A refreshing antidote to the political and economic slants that commonly color and distort news coverage of topics like the greenhouse effect, air quality, natural disasters and global warming, Real Climate is a focused, objective blog written by scientists for a brainy community that likes its climate commentary served hot. Always precise and timely, the site's resident meteorologists, geoscientists and oceanographers sound off on all news climatological, from tropical glacial retreat to "doubts about the advent of spring."
    In 2006, Nature compiled a list of the 50 most popular blogs written by scientists, as measured by Technorati. RealClimate was number 3 on that list."
    http://en.wikipedia.org/wiki/RealClimate

    Do you think realclimate.org is a biased source, or were you just making a general point?
     
  19. Jul 21, 2007 #18

    Evo

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    Making a general point. I'm all for allowing links to science blogs, I see them as a good way to see current dialog between experts in the field. Also, a lot of members do not have access to peer reviewed papers and can read abstracts only.
     
  20. Jul 22, 2007 #19
    I might also point out that the article cited by BillJx is written by a physicist and noted historian, in collaboration with another scientist with impeccable credentials.

    I recommend reading both part 1 and 2, as it puts into perspective the saturation argument. Since the debate took place for more than a century, and was finally put to rest in 1938.
     
  21. Jul 22, 2007 #20
    Yes, it was a good article, thanks BillJX, I wasn't aware of that site. It clears up something that I had been mulling over in my mind for some time: how the "saturation argument" could be flawed because it failed to account for the depth of the atmosphere.
     
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