Climate change: the future.

  • Thread starter billiards
  • Start date
  • #1
765
15
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?
 

Answers and Replies

  • #2
Mk
1,984
3
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.
 
  • #3
jambaugh
Science Advisor
Insights Author
Gold Member
2,238
268
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" [Broken]
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: http://pubs.giss.nasa.gov/abstracts/1993/Cess_etal.html" 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 by a moderator:
  • #4
Ivan Seeking
Staff Emeritus
Science Advisor
Gold Member
7,234
210
See: http://www.john-daly.com/artifact.htm" [Broken]
What is this source? Is it peer reviewed or just a blog?
 
Last edited by a moderator:
  • #5
Ivan Seeking
Staff Emeritus
Science Advisor
Gold Member
7,234
210
The source site looks to be crackpot

Climate and climate change has been a lifelong study of mine since my early days as a ship's officer in the British Merchant Navy. I have lived through and traced the progress of the `ice age' scare of the 1970's, the `nuclear winter' scare of the 1980s, and now the `global warming' scare of the present. All these scares have advanced the interests of what was a small academic discipline 30 years ago to become a mammoth global industry today. It is my view that this industry has, through the `politics of fear' which it has promoted, acted against the interests of the public.
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.
 
  • #6
Ivan Seeking
Staff Emeritus
Science Advisor
Gold Member
7,234
210
According to the definitive source on this matter - the IPCC:

Warming of the climate system is unequivocal, as is now evident from observations of increases in global average air and ocean temperatures, widespread melting of snow and ice, and rising global average sea level (see Figure SPM.3). {3.2, 4.2, 5.5}
The understanding of anthropogenic warming and cooling influences on climate has improved since the TAR, leading to very high confidence7 that the global average net effect of human activities since 1750 has been one of warming, with a radiative forcing of +1.6 [+0.6 to +2.4] W m–2 (see Figure SPM.2). {2.3., 6.5, 2.9}

...6 In this Summary for Policymakers, the following terms have been used to indicate the assessed likelihood, using expert judgement, of an outcome or a result: Virtually certain > 99% probability of occurrence, Extremely likely > 95%, Very likely > 90%, Likely > 66%, More likely than not > 50%, Unlikely < 33%, Very unlikely < 10%, Extremely unlikely < 5% (see Box TS.1 for more details).

7 In this Summary for Policymakers the following levels of confidence have been used to express expert judgements on the correctness of the underlying science: very high confidence represents at least a 9 out of 10 chance of being correct; high confidence represents about an 8 out of 10 chance of being correct (see Box TS.1)
http://ipcc-wg1.ucar.edu/wg1/Report/AR4WG1_Pub_SPM-v2.pdf [Broken]
 
Last edited by a moderator:
  • #7
Mk
1,984
3
What is this source?
just a blog?
crackpot
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.
the definitive source on this matter - the IPCC
Did your three posts thoughtfully criticize his facts yet?
 
  • #8
Integral
Staff Emeritus
Science Advisor
Gold Member
7,201
56
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.
 
  • #9
jambaugh
Science Advisor
Insights Author
Gold Member
2,238
268
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
 
  • #10
765
15
What about this attached graph (found here http://www.geosc.psu.edu/~kump/KumpCommentary.pdf [Broken]), I know I said I didn't want to look back, but it's hard to dispute the correlation between CO2 and temp in this high resolution record.
 

Attachments

Last edited by a moderator:
  • #11
mheslep
Gold Member
311
728
According to the definitive source on this matter - the IPCC:
Why must the IPCC be considered 'definitive'? It may be 'persuasive', 'informed', 'well sourced', etc. but who says its definitive.
 
  • #12
Evo
Mentor
23,164
2,864
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.

After some prolonged deliberation, I have decided to withdraw from participating in the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC). I am withdrawing because I have come to view the part of the IPCC to which my expertise is relevant as having become politicized. In addition, when I have raised my concerns to the IPCC leadership, their response was simply to dismiss my concerns.

With this open letter to the community, I wish to explain the basis for my decision and bring awareness to what I view as a problem in the IPCC process. The IPCC is a group of climate researchers from around the world that every few years summarize how climate is changing and how it may be altered in the future due to manmade global warming. I had served both as an author for the Observations chapter and a Reviewer for the 2nd Assessment Report in 1995 and the 3rd Assessment Report in 2001, primarily on the topic of tropical cyclones (hurricanes and typhoons). My work on hurricanes, and tropical cyclones more generally, has been widely cited by the IPCC. For the upcoming AR4, I was asked several weeks ago by the Observations chapter Lead Author - Dr. Kevin Trenberth - to provide the writeup for Atlantic hurricanes. As I had in the past, I agreed to assist the IPCC in what I thought was to be an important, and politically-neutral determination of what is happening with our climate.<snip>

It is beyond me why my colleagues would utilize the media to push an unsupported agenda that recent hurricane activity has been due to global warming. Given Dr. Trenberth’s role as the IPCC’s Lead Author responsible for preparing the text on hurricanes, his public statements so far outside of current scientific understanding led me to concern that it would be very difficult for the IPCC process to proceed objectively with regards to the assessment on hurricane activity. My view is that when people identify themselves as being associated with the IPCC and then make pronouncements far outside current scientific understandings that this will harm the credibility of climate change science and will in the longer term diminish our role in public policy.
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:
  • #13
mheslep
Gold Member
311
728
..., but it's hard to dispute the correlation between CO2 and temp in this high resolution record.
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:
  • #14
765
15
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?
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:
  • #15
BillJx
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" [Broken]
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.)
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
 
Last edited by a moderator:
  • #16
Evo
Mentor
23,164
2,864
Just a caution, www.realclimate.org is a blog and is non-peer reviewed. Blog posts can be considered opinion only.
 
Last edited:
  • #17
BillJx
Just a caution, www.realclimate.org is a blog and is non-peer reviewed. Blog posts can be considered opinion only.

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?
 
  • #18
Evo
Mentor
23,164
2,864
Do you think realclimate.org is a biased source, or were you just making a general point?
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.
 
  • #19
Skyhunter
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.
 
  • #20
765
15
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.
 

Related Threads on Climate change: the future.

  • Last Post
Replies
17
Views
6K
  • Last Post
Replies
12
Views
5K
  • Last Post
2
Replies
27
Views
6K
  • Last Post
Replies
2
Views
5K
Replies
4
Views
724
  • Last Post
2
Replies
33
Views
7K
  • Last Post
Replies
1
Views
6K
  • Last Post
Replies
4
Views
5K
  • Last Post
2
Replies
35
Views
4K
Replies
3
Views
5K
Top