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Climate Hustle

What do the hacked CRU emails tell us?

Posted on 22 November 2009 by John Cook

Earlier this week, the servers at the University of East Anglia were illegally hacked. Emails dating back to 1996 were stolen and leaked onto the web. Phil Jones, the director of the Climate Research Unit, has confirmed the emails are not forgeries although there is over 60Mb worth of material - they can't guarantee all of it is genuine. What does it all mean? Michelle Malkin labels it the global warming scandal of the century (of course the century is only 9 years old but even 'scandal of the decade' would be no mean feat). James Delingpole at the UK Telegraph claims the emails are the final nail in the coffin of 'Anthropogenic Global Warming'? So just what do these emails tell us?

Some of the emails must be embarrassing for the authors. One email responds in poor taste to the death of a well known skeptic. There's scathing discussion of skeptics such as Steve McIntyre and Roger Pielke, including imaginings of violence. However, the crucial question is whether these emails reveal that climate data has been falsified. The most quoted email is from Phil Jones in 1999 discussing paleo-data used to reconstruct past temperatures (emphasis mine):

"I've just completed Mike's Nature trick of adding in the real temps to each series for the last 20 years (ie from 1981 onwards) and from 1961 for Keith's to hide the decline."

What do the suggestive "tricks" and "hiding the decline" mean? Is this evidence of a nefarious climate conspiracy? "Mike's Nature trick" refers to the paper Global-scale temperature patterns and climate forcing over the past six centuries (Mann 1998), published in Nature by lead author Michael Mann. The "trick" is the technique of plotting recent instrumental data along with the reconstructed data. This places recent global warming trends in the context of temperature changes over longer time scales.

The "decline" refers to the "divergence problem". This is where tree ring proxies diverge from modern instrumental temperature records after 1960. The divergence problem is discussed as early as 1998, suggesting a change in the sensitivity of tree growth to temperature in recent decades (Briffa 1998). It is also examined more recently in Wilmking 2008 which explores techniques in eliminating the divergence problem. So when you look at Phil Jone's email in the context of the science discussed, it is not the schemings of a climate conspiracy but technical discussions of data handling techniques available in the peer reviewed literature.

In the skeptic blogosphere, there is a disproportionate preoccupation with one small aspect of climate science - proxy record reconstructions of past climate (or even worse, ad hominem attacks on the scientists who perform these proxy reconstructions). This serves to distract from the physical realities currently being observed. Humans are raising CO2 levels. We're observing an enhanced greenhouse effect. The planet is still accumulating heat. What are the consequences of our climate's energy imbalance? Sea levels rise is accelerating. Greenland ice loss is accelerating. Arctic ice loss is accelerating. Globally, glacier ice loss is acceleratingAntarctic ice loss is accelerating.

When you read through the many global warming skeptic arguments, a pattern emerges. Each skeptic argument misleads by focusing on one small piece of the puzzle while ignoring the broader picture. To focus on a few suggestive emails while ignoring the wealth of empirical evidence for manmade global warming is yet another repeat of this tactic.

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Comments 1 to 50 out of 121:

  1. As I posted earlier on another site, let me know when they find the e-mails that show our understanding of the physics is wrong. Until then this is just dirt.

    However it is amusing to see what is being quoted as the "smoking gun". For example this:

    “Since the IPCC makes it quite clear that there are substantial grounds for concern about climate change, is it not partially the responsibility of climate science to make sure only satisfactorily peer-reviewed science appears in scientific publications? – and to refute any inadequately reviewed and wrong articles that do make their way through the peer review process?”

    is being offered as "Evidence of an organized subversion of the peer review process". Also Soon (2003) is being dragged up as evidence of blacklisting of scientific journals. I would have though they would have wanted Soon 2003 to remain buried as long as possible.

    My recommendation, sit back, grab some popcorn and watch as this unfolds.

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  2. Scientists are as cynical as the rest of us so you can't read too much into personnel emails ......but....... ouch. you may think I'm a climate skeptic but really what I am is critical of individuals making too much of their research and more importantly media and politicians blowing situations out of proportion. Nobody wants to see science smeared by careerists.

    There's popcorn downstairs I better go and get it!!
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  3. @realclimate I left the following message:

    It is true that hackers are a problem nowadays, my linux box reports many break in attempts, but to the best of my knowledge nobody ever passed the defense lines. The stolen CRU data which is now publicly made available causes quite some trolling on the internet. But so far I’ve not seen anything coming close to disclosing global warming as a scam or whatever is claimed by the trolls and the global warming deniers.

    Meanwhile the consequences of global warming continue to become available and they have absolutely nothing in common with the CRU data center. Greenland is for instance showing accelerated melting, it is picked up as a gravity feature, as shown last week in Science. And such results will fill the peer-reviewed journals for the next coming years.

    Let me add:

    The interesting point we will hopefully learn is whether there is a bias in science research, which is a fundamental problem not resolved by peer review. One of my students suggested an improvement therefore to the peer review system, he said, lets make the system double blind, meaning that a reviewer doesn't know who the author is and the other way around also, that authors don't know who reviewers are (which is actually my default mode as reviewer).
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  4. This is pathetic. "Skeptics" have declared that anything goes. It would be of course equally low to hack McIntyre or Watts' personal e-mails, and those of the think tanks and industries hostile to action. Yet I can't help to think it would only be equitable to have all their dirt posted on the internet as well. Just to see who's really more dishonest in the whole "debate."
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  5. @Philippe: Scientists do often fight like little children, it is well known and unfortunately now also publicly exposed. What does matter is, is the physics right, and can somebody who is not involved in the discussion come to the same conclusion within the same boundary conditions of course. If that is not the case then all bells and whistles should go off, but I don't expect this to happen with the Hockey stick, because Mann's finding was independently confirmed already.
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  6. This just reconfirms that scientists are human beings. No surprise there I hope.
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  7. Um, the most important word in the email is "hide". If the decline were actually not real(say if it were a statistical artifact), it would not need to be hidden.

    In any case, frankly, I don't think that there is much new here in terms of the scientific issues. It seems to me that anyone with a decent understanding of the issues should probably recognize 1.that tree ring reconstructions are based on some pretty shaky science and 2. that there is a pretty decent chance that recent temperature changes are not all that unprecedented(being slightly warmer than MWP perhaps).

    Obviously, many people have been saying for a long time that 1&2 are true and these emails give them significant validation IMO.

    Also, since a couple of folks have brought up the fact that the physics are still right, it bears repeating that current predictions are not based solely on physics, but also on computer simulations that parameterize atmospheric effects.

    Cheers, :)
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  8. A page worth reading: Newtongate: the final nail in the coffin of Renaissance and Enlightenment ‘thinking’. It looks like they've actually read through actual correspondance to, from and about Isaac Newton to find incriminating excerpts.
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  9. Thanks for this post, John. Is it right to say, then, that the decline needed to be 'hidden' because it was in the case referred to shown by the tree-ring proxy data, which, given your comments about sensitivity, would have been a distortion to include in that case?

    If so, bad choice of word (though it wasn't being chosen for publication), but no problem for climate science.

    I, and not doubt other lay readers, really appreciate the clarity of your writing here - Thanks.
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  10. Um, the most important word in the email is "hide". If the decline were actually not real(say if it were a statistical artifact), it would not need to be hidden.

    The decline isn't real. The instrumental temperature record shows that it isn't real. Global temps over the last fifty years have not declined, they've increased, despite the tree-ring data.

    So in essence what's happening here is an attempt to graph out what scientists believe to be the best reconstruction of past to present temps they can.

    Gavin Schmidt agrees that the graph created for the WMO brochure should've been more comprehensively labelled, but this has nothing to do with the science. Mann explained exactly what he did and why he did it in his Nature article. All out in the open, nothing "hidden".

    The divergence problem is real. As John mentions in his top post, it's been discussed a lot in the literature, and is an area of active research. Denialists - Jeff Id currently is perhaps the most vehement in this view - claim that tree ring proxies can't accurately reflect temperature at all. This is bull. We know that properly situated trees are sensitive to temperature changes due to extensive work into plant (including tree) physiology (and, remember, trees are a valuable agricultural crop so most of this research has had nothing to do with the climate change debate). We also know it is bull because such reconstructions closely match other proxy reconstructions. Also, not all dendro datasets show the divergence problem.

    Is it right to say, then, that the decline needed to be 'hidden' because it was in the case referred to shown by the tree-ring proxy data, which, given your comments about sensitivity, would have been a distortion to include in that case?

    I'd say it's simpler - the decline shown by the tree-ring proxy data over recent decades can't be real because the instrumental record shows it's not real.
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  11. For the science, this has minimal impact. I have seen a couple of comments from more skeptical scientists who in fact have gotten more confidence by seeing that these guys are almost obsessed with science.

    It will lead to even more focus on openness, quality and the peer review process. Very good. It wouldn't harm with a bit more focus on ethics, either. In the RC posting about this they pointed to Newton, who was no angel. OK, then I would say that Newtonian ethics is much more outdated than Newtonian mechanics :-)

    The political impact will be much bigger, but mostly short term. The IPCC will be more dependent on the science and the reasoning, and less on the authority of leading scientists. It may be a setback for international negotiations, but not for very long. And I think we may even get better and more robust policy measures this way.

    The most important thing in the current situation, is that the models have been somewhat oversold, and the IPCC estimates have not been as conservative as they should be. In addition lots of time and energy has been used unproductively on tree-rings, hockey-sticks and "unprecedented warming". Look at this discussion, too: The divergence problem is real, and interesting, but how much of current climate science depends on it, really? To me, it seems mostly to fuel denialists' attacks.

    The present situation, where feedback estimates tend to be reduced over time, is most unfortunate. James Hansen's old curves, using 4 deg/doubling, may increasingly be used as examples of "alarmism" by "skeptics" and among the leaked emails can be found what Kevin Trenberth wrote to Tom Wigley 20091014:
    "How come you do not agree with a statement that says we are no where close to knowing where energy is going or whether clouds are changing to make the planet brighter. We are not close to balancing the energy budget." This is of course relative to Trenberths very high standards, but still quite different from the impression of rather small uncertainties. Which is also borne out by the models not performing very well for the last decade. In fact, a few more years with little or no warming would show them to be in error - something that would not have happened with more conservative estimates. According to the models, the development of the last decade is a bit anomalous - I'm not sure it is, and something like what has happened, should have been announced in advance.
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  12. @dhogaza Thanks for further explaining that. I'm not sure I understand why a change would occur in sensitivity, but I'm not a scientist. That what was claimed to be hidden was in fact explicit in the literature is, I think, sufficiently reassuring.

    As for the denialists, I'm sure they'll continue to make capital of this stuff, but the point about the broader, and quite obvious, climate picture should serve as a powerful contradiction to their nonsense.
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  13. The emails have been archived in a searchable form here.

    I was wondering what peoples thoughts are on this comment from one "Despite its relatively small size, CRU has had (and continues to have!) a rather remarkable "fingerprint" in the world of climate science."
    I had wondered about the influence of this organisation.
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  14. I'm not sure I understand why a change would occur in sensitivity, but I'm not a scientist.

    It doesn't matter that you're not a scientist, because they don't understand either.

    That's why the divergence problem is ... a problem! :)

    Seriously ...

    But they're working on it. You might google "Liebig's Law of the Minimum". In plain language, this essentially says that growth is typically limited by the most scarce resource/factor. For a tree up high near the specie's tree line, this is often temperature, often the number of warm days over a short period of summer. Lower down, you may find many more warmer days, the same precip, the same nutrients more or less, and growth patterns will be different because the scarcest resource might be (say) soil nitrogen. It's warm enough so the tree will grow rapidly enough to be limited by that rather than temps.

    Does this make sense to you?

    So the confounding factor as temps have warmed for some of the series might simply be that temperature is no longer the most limiting factor. Maybe precip has dropped. Maybe something else is going on.

    This is the kind of stuff they're working on - trying to understand what factors have changed to cause growth patterns to change.

    I think they'll work it out. Science typically does ...
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  15. I am somewhat surprised by these responses. I find significant problems with the following discoveries in the emails:
    1) Tree ring data is good when it supports the hypothesis, but must be hidden when it conflicts? None of you take issue with that?
    2) Through the email text it is pretty clear that their approach is to validate data based on how well it fits to the hypothesis, not how well the hypothesis fits to the data
    3) Why is it ok to obstruct the freedom of information act? What do they have to hide?
    4) Why do they collude to exclude peer review of articles that question their hypothesis, I find it most disturbing since they use the lack of peer review to discredit the skeptics. This truly brings into question both their ethics and scientific agenda.

    The models have been notoriously inaccurate in making future projections, and now we find that even the week claims of model accuracy are nothing more than the result of massaged data. There is an old saying, that if you torture the data enough, it will confess.
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  16. TruthSeeker, refer to @dhogaza at the end of comment 10 re the evidence of the instrumental record. I guess you don't say the instruments have stopped working because the tree-rings don't agree.

    Comment 14 goes on to suggest that other factors may well be in play re the tree-rings. For example, I might grumpily say it's hot and that has been a good proxy for the outside temperature in the past (e.g. I tend to say it when it reaches about 25C inside), but while I'm away on a work trip my wife installs an air-conditioner and sets the thermostat at 22C - pleasant but not necessarily obvious.

    Having lazed away the weekend inside on returning from my trip, would I sit there looking in disbelief at a TV weather report of 37C, or go looking for another explanation (i.e. the new air-conditioner)? I don't think I'd be suggesting there was something wrong with the instruments of the meteorologists, do you?

    I'd also imagine that the tree-rings would have continued to be a good proxy had the conditions in which they formed remained continuous in the divergence period with the time when they more closely reflected temperature.
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  17. Interesting. You provide anictdotal evidencen to suggest that Tree rings are no longer any good while I suggest that if they arn't currently any good who has evidece that they were ever any good.
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    Response: The evidence that tree-rings are a reliable proxy can be found in Briffa 1998 that show tree-ring width and density show close agreement with temperature back to 1880. To examine earlier periods, one study split a network of tree sites into northern and southern groups (Cook 2004). While the northern group showed significant divergence after the 1960s, the southern group was consistent with recent warming trends. This has been a general trend with the divergence problem - trees from high northern latitudes show divergence while low latitude trees show little to no divergence. The important result from Cook 2004 was that before the 1960s, the groups tracked each other reasonably well back to the Medieval Warm Period. Thus, the study concluded that the current divergence problem is unique over the past thousand years and is restricted to recent decades. More on the divergence problem...
  18. The "trick" to "hide the decline" dates from 1999. As 1998 was a record hot year, it is hard to imagine what real decline in temperatures the sceptics/deniers think was occurring that needed to be hidden.
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  19. The "trick" to "hide the decline" dates from 1999. As 1998 was a record hot year, it is hard to imagine what real decline in temperatures the sceptics/deniers think was occurring that needed to be hidden.

    You're thinking the wrong way round.

    It's not that they were using a 'trick' to hide a divergence. They were using a trick to hide a 'decline'

    That was the language used. I've no reason to believe that they didn't mean what they said.

    ie. It's a case of manipulating things to fit the hypothesis, not trying to explain what doesn't fit the hypothesis.

    Combine that with all the other details in the emails and it shows a particular unpleasant group of people.

    Imagine plotting to get a PhD removed from a student because their results were awkward?

    In reality, its a disaster for climate change advocates.

    They have been hiding data, and its clear they have done this now. They have also talked about destroying data that is subject to a FOI request. That is a criminal offence in the UK
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  20. A general point

    There are lots of vague references to what are presumably rather specific emails. If anyone makes a comment about a particular point, why not specify exactly what email(s) the point refers to. Then we can assess the context etc.

    This relates to post #13 (HumanityRules extraced single sentence), post #15 (Truthseekers list), post #19 (Nickle's PhD comment) etc.

    HumanityRules (post #13) has linked to the hacked archive. So simply put the date of the email(s) that you are referring to, rather than posting single extracted sentences or making unspecified assertions.
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  21. dhogaza,

    The decline is the divergence problem, you can't say one is real and not the other. IAC, the point is, if we know that recent tree ring data for which we have independent temperature data shows that tree rings are not (currently) a good temperature proxy, why should we assume they were a good proxy for times when we do not have much independent temperature data?

    Confirmation bias, anyone?

    Cheers, :)
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  22. The decline is the divergence problem, you can't say one is real and not the other. IAC, the point is, if we know that recent tree ring data for which we have independent temperature data shows that tree rings are not (currently) a good temperature proxy, why should we assume they were a good proxy for times when we do not have much independent temperature data?

    Confirmation bias, anyone?


    1. Not all tree ring data sets show the divergence problem, yet they show the same general pattern of climate in the past than those that do.

    2. There are a dozen or so paleo reconstructions that DON'T USE TREE RING DATA AT ALL that show a similar pattern in past climatic conditions.

    3. We know from tree physiology unrelated to paleoreconstructions that trees near their altitudinal and latitudinal range limits are frequently growth-limited by temperature.

    4. They don't just count tree rings, but rather for variation in tissue that is known from studies into tree physiology to be due to temperature being a limiting factor in growth.

    etc etc etc.

    The problem with simplistic rejection of science you don't understand is that unlike you, specialists *do* understand their subject very well.

    Which leads to statements like:

    4)Libel?? see tree rings, they use it when it supports their claims and through it out when it contridicts. That isn't libel that is true and has as you say "something that's been widely discussed in the open professional literature for a decade."
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  23. re #24:

    Your points don't make a lot of sense TruthSeeker.


    a). There isn't really anything hidden. Briffa et al. themselves highlighted the divergence issue already in 1998 in Nature, and pointed out the late 20th century lack of response of high latitude trees to rapid warming meant that this part of a reconstruction was demonstrably incorrect [*]. However the tree response to temperature was reliable over the previous decades of the 20th century and back to the 1880’s. So that defines a range of temperature responses (range/rates) in which the proxy is expected to provide reliable temperature reconstructions in the past.

    b) Since we now have paleotemperature reconstructions from a large range of proxies and that don’t involve tree rings (e.g. [**]), and cover the same period as the ones under discussion in these very old emails, we can see that the analyses of 1998 have pretty much held up to the test of time.

    5) Not sure what you mean there. Please clarify.

    6) This is about one paper out of 1000’s of papers published in the climate-relate field. It was so obviously dodgy that the failure of the review process caused the editorial board of Climate Research to resign, and the publisher himself stated that the paper shouldn’t have been published as it was. If we have to pretend that we can’t recognise rubbish when we see it, then we’re in trouble (and easy prey for propagandists and other charlatans).

    7) Not sure what you’re referring to there. No-one decides what is or isn’t peer-reviewed other than an editor, and it’s very unlikely that an editor wouldn’t send a paper for peer-review, unless possibly if it didn’t conform to the requirements of the journal (character length, number of figure in a communication, etc), or if it's a paper sent to Nature or Science, in which case an editorial decision is made about whether a paper makes it past a preliminary hurdle based on “general interest”, “sexiness”, or “newsworthiness”.

    [*] K. R. Briffa et al. (1998) Reduced sensitivity of recent tree-growth to temperature at high northern latitudes Nature 391, 678-682

    [**] M. E. Mann (2008) Proxy-based reconstructions of hemispheric and global surface temperature variations over the past two millennia. Proc. Natl. Acad. Sci. USA 105:13252-13257
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  24. re #13 HumanityRules, I'm not going to link to the email you're referring to, since it's a personal email that refers to the inability of a distinguished scientist to sttend a meeting due to illness. It's pretty obvious that the phrase is part of a general personal reminiscence between scientists.

    The CRU is a leading institution in climate research. It's one of the three centres that compile surface temperature data for constructing past and contemporary temperature anomalies from direct surface temperature measurements. You can learn about it here:
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  25. "places recent global warming trends in the context of temperature changes over longer time scales" John, excellent explanation - after following all the RC thread I still hadn't understood what was being said until I read your few lines. And dhogaza - "The decline isn't real. The instrumental temperature record shows that it isn't real. Global temps over the last fifty years have not declined, they've increased, despite the tree-ring data" - full marks too for a clear explanation. Astonishing to think that this nonsense is the thing that is getting Deniaworld excited. I have a discussion here about the context what is going on.
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    Response: Normally, WWII analogies in climate discussions are a bad idea. But the dropping of foil plates to mask the Allied invasion is an apt metaphor.
  26. Readers of this blog may be interested in a very recent paper which seems to be able to solve the tree ring mystery:

    "Recent unprecedented tree-ring growth in bristlecone
    pine at the highest elevations and possible causes".

    Matthew W. Salzer, Malcolm K. Hughes, Andrew G. Bunn, and Kurt F. Kipfmueller
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  27. I just want to give an example of how this is playing out around the world. Aftenposten, the most influential Norwegian newspaper, has been running a lot of good articles on climate change. But when this turns up, it is handled as classical conflict stuff, and the basic journalistic principle is to give both sides equal opportunities and weight. In today's article, the "skeptic" side is represented by a well-known "skeptic", professor Olav Martin Kvalheim, University of Bergen.

    Kvalheim refers to "Mike's Nature trick", and I have no doubt he is able to understand this, but he still presents this as proof of data manipulation:

    "This, in Kvalheim's opinion, shows how temperature measurements are manipulted to fit with the model of temperature rise in cliate crisis".

    He then continues to talk about big research money, to end up with:

    - Aren't there even stronger economical interests on the skeptics' side?

    - You mean that the oil and car industry support the skeptics? No. From the skeptics' side this is pure idealism - many view the climate panel as a propaganda machine, and want to defend scientific principles.

    I really hadn't believed he would spin it in such a cheap and dirty way. But the impact is much more short-lived this way, and he surely isn't increasing his credibility in the informed public debate in Norway.
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  28. Eh. This is being discussed at great length everywhere else. Why bother to jump in? As far as I can tell, it's all about personalities, not so much about science.

    Your site's niche market is presenting well-written, clear, informative, and interesting explanations of science topics, often with mentions of papers that don't receive a lot of publicity elsewhere.

    My opinion doesn't really matter, but I'd encourage you to generally ignore whatever the manufactured controversy of the week may be, and just keep writing about the science.

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  29. dhogaza, I personally don't find tree ring reconstructions all that interesting so I won't debate them at length. I think it is pretty clear though that we don't know why tree rings stopped being good temperature proxies(Briffa 1998 says this). If the tree ring proxies currently suggest that the temperature should be 0.5C cooler than they actually are, how do we know that the last time they read as 0.5C cooler than now, they aren't equally warm as today(or warmer)?

    As to the fact that other paleoclimate reconstructions agree, IMO this depends on which ones you use, of course(which is where confirmation bias comes in). CO2 science has at least a couple of dozen papers that would argue that the MWP was warmer than currently. Personally, I don't have an opinion one way or another, but temperature reconstruction is very tricky IMO.

    Cheers, :)
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  30. John, I must say that I was disappointed to see you weigh in on this CRU fiasco. The first 24 comments here were pretty constructive, but now it seems that some people feel it is OK to adopt a 'carpet bombing' approach to posting. Isn't that trolling?

    Others, RC et cetera are doing a good job of stemming the tide of nonsense that can be expected to arise out of this fiasco. Not that those in denial will pay any attention to context or reason, they made up their minds years ago and now this fiasco is just feeding their bias and preconceived ideas. They will read and see what they want to, regardless of the truth.

    This CRU hack story is about egos and politics and money for those in denial. It is best left up to the police, lawyers and judges to sort it out now. I sure do hope ClimateAudit and AirVent and WUWT have good lawyers.....

    Anyhow, the planet continues to warm, and there is still much science to discuss and advance; and you do an excellent job of that. Can we please stick to that much more interesting and important task? Thanks.
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    Response: My initial reaction when the news first broke was to ignore it. But as it unfolded, I realised it would be a mistake to let skeptic blogs write the narrative on this issue. The whole approach of Skeptical Science is to point out that global warming skepticism misleads by focusing on narrow pieces of the puzzle while neglecting the broader picture - the job of Skeptical Science is to communicate the broader picture. The case of the CRU hack is a textbook example of this tactic - focusing on a few suggestive emails to discredit the entire field of climate science while neglecting the wealth of empirical evidence for man-made global warming. This point needed to be made but I'll be happy to move on to worthier topics as soon as I can (believe me, I'm working on it).
  31. I wasn't going to bother addressing this thread at all, then felt compelled to respond to some obvious howlers.

    There's an interesting bit of sociopolitics involved, with some nasty precedents. In fact I think climate scientists are maybe allowing themselves to become rather over-involved with the rubbish from the pseudoskeptics. Why not just ignore all this crap, don't have anything to do with it, and just get on with doing and publishing the science?

    Unfortunately, it just isn't that simple. There's a similarity with the McCarthyist calamity of an earlier age (apols for a slight descent towards breaking Godwin's Law, but some specific similarities are quite strong) where the very act of accusation to contrive a psychology of distrust, forces a response in the accused which may well come across as sounding a little defensive (although in fact the responses have been admirably robust!).

    Inevitably, by responding to contrived accusation, a "controversy" is constructed where the focus is shifted away from the science into a sort of miasma of real and imagined deceit in which the pseudoskeptic "accusers" are comfortable. And those that may not care to engage with the science but surely know how to enjoy a witch-hunt, are all too happy to chip in with their own "interpretations"...

    So yes, this site should be encouraged to continue to focus on the "light" and leave the "heat" elsewhere, 'specially since John Cook does such a fantastic job of fairly dispassionate description and documentation of the science.
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  32. I second with chris here. I thought maybe the political/public impacts of this might be somewhat interesting, but I realize that is not an area of focus for this site, and I'm _very_ happy with that. Keep up the good work, John!

    For the subject matter of the leak, I think RC is the best place right now.

    That said, I think there may be quite a few points raised by the material that we might, perhaps even should, discuss here, if we want to be really skeptical. It's just quite pointless to go into it in a more general discussion like this one. Rather, it may be brought up where it properly belongs, like in treatments of proxies, different temperature reconstructions, energy budget balancing, forcing/feedback estimations etc.

    "Light" vs "heat". Yes, exactly.
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  33. As to the fact that other paleoclimate reconstructions agree, IMO this depends on which ones you use, of course(which is where confirmation bias comes in).

    They're selected objectively, but of course you'll never be convinced of this.

    But I love the way confirmation bias is *assumed*.
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  34. You mention above that “ seas level rise is accelerating”. But a recent ( June 2009 ) scientific paper by Cliff Ollier of the School of Earth and Environment, The University of Western Australia, states as follows :
    Abstract: Graphs of sea level for twelve locations in the southwest Pacific show stable sea level for about ten years over the region. The data are compared with results from elsewhere, all of which suggest that any rise of global sea level is negligible. The Darwin theory of coral formation, and subsidence ideas for guyots would suggest that we should see more land subsidence, and apparent sea level rise, than is actually occurring. Sea level studies have not been carried out for very long, but they can indicate major tectonic components such as isostatic rebound in Scandinavia. Attempts to manipulate the data by modelling to show alarming rates of sea level rise (associated with alleged global warming) are not
    supported by primary regional or global data. Even those places frequently said to be in grave danger of drowning, such as the Maldives.
    Also, in an interview with Dr. Nils-Axel Mörner (head of the Paleogeophysics and Geodynamics department at Stockholm University in Sweden, past president (1999-2003) of the INQUA Commission on Sea Level Changes and Coastal Evolution, and leader of the Maldives Sea Level Project – he has been studying the sea level and its effects on coastal areas for some 35 years) by EIR (Argentine Foundation for a Scientific Ecology) [] he talked about the IPCC misrepresentation of sea level data: “Then, in 2003, the same data set, which in their [IPCC's] publications,... was a straight line—suddenly it changed, and showed a very strong line of uplift, 2.3 mm per year, the same as from the tide gauge... It was the original one which they had suddenly twisted up, because they entered a “correction factor,” ... I accused them of this at the Academy of Sciences in Moscow —I said you have introduced factors from outside; it's not a measurement. It looks like it is measured from the satellite, but you don't say what really happened. And they answered, that we had to do it, because otherwise we would not have gotten any trend! That is terrible! As a matter of fact, it is a falsification of the data set. ... So all this talk that sea level is rising, this stems from the computer modeling, not from observations. The observations don't find it! I have been the expert reviewer for the IPCC, both in 2000 and last year. The first time I read it, I was exceptionally surprised.
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  35. Do we *really* have to put up with the cut-and-paste flooding?
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  36. re #43/44

    neilperth you're just cutting and pasting's very boring and tedious.

    Cliff Ollier hasn't published anything in the scientific literature since 2007, unless he's decided to publish under a different name. Please cite or link to the "June 2009" paper that you are referring to.

    No one is going to be taken in by the Morner nonsense here. Surely you can find a more appropriate site to peddle this dreary stuff designed for the gullible.

    Dr. Morner is not the most reliable of sources [*] and hearsay and unverified allegations are boring. If you can't find any science that pertains to a subject, why bother posting. If you want to learn about contemporary sea level measurements, you can look at the science here:


    The long cut 'n paste nonsense from your post #44 is from an email sent by someone to a climate scientist. It contains a typical trail of previous emails, one of which contains the trash that you've cut 'n pasted for our edification. It would help if you were to think about what you post, before dumping junk.

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  37. I see that some posters on this thread are calling for it to be closed. The point is that the hacked Hadrut emails give an insight into what is going on at Hadcrut, This is where much of the scientific data comes form on which you people base your scientific analyses of the climate.

    The excerpts I have posted raise legitimate questions about the lack of impartiality shown by some climate research scientists. They also show that interpretation of the climate data often produces ambiguous results and that the science is far from settled.

    There is also correspondence between some climate research scientists and organisations such as WWF and Greenpeace with regard to when certain announcements on the findings of the scientists should be made to the press in order to have maximum effect on upcoming intergovernmental meetings and onferences.

    You are free to read the full email transcripts on the Net.

    Closing this thread will not look good and will be interpreted as a denial that the legitimate questions I have raised above exist.
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  38. dhogaza,

    "Objectively" chosen or not, temperature reconstructions being what they are, it is virtually unavoidable to separate measurements into the ones that reflect a real temperature signal and those that do not. You have to make some assumptions one way or the other. If you already know what the "correct" answer is, it is human nature(at least IMO) to be more likely to reproduce that answer again.

    If you didn't have to choose which records reflected the true signal and which didn't, confirmation bias wouldn't matter.

    Cheers, :)
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  39. Chris your post stating that " Cliff Ollier hasn't published anything in the scientific literature since 2007,"

    please find below the reference to the Cliff Ollier paper.

    Ollier C (2009 ), Sea level in the Southwest pacific is stable. New concepts in global tectonics. No 51, June 2009.

    I thought you were keeping up with such important research.
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  40. "New Concepts in Global Tectonics" isn't a scientific journal neilperth. It's a newsletter, and it certainly contains some weird stuff.

    As I pointed out above, Ollier hasn't published anything in the scientific literature since 2007. It's pretty straightforward to establish that. What people say in newsletters isn't always very interesting or enlightening for dispassionate understanding.
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  41. Neil Perth,

    "As Corcoran points out, "the IPCC has depended on 1) computer models, 2) data collection, 3) long-range temperature forecasting and 4) communication. None of these efforts are sitting on firm ground.""

    This is off topic, as have several of your posts. Are you a Canuck? I am, that is why I know exactly who Terrence (Terry) Corcoran is. He is a neocon editor at the infamous "and almost bankrupt" Financial Post (Canadian paper, I use the term "paper" loosely). Rumour has it is that he is on the take from big oil....

    Anyhow, he alleged pillars of AGW are nonsense. That said, yes, scientists need to do a better job of clearly communicating their findings.

    I would strongly advise you not to solicit your 'scientific' knowledge from the likes of Terrence, but it seems that you think quite highly of him and his and others' pseudo science.

    PS: You do know the editors at the National Post (a sister paper of Financial Post) have even acknowledged recently that AGW is real (an editorial on 7 November 2009).
    PPS: THe NP and FP have NO ethical guidelines and are not a member of any group or organization in Canada which can hold them accountable for misconduct.
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  42. John,
    You start the comments by saying, "...let me know when they find the e-mails that show our understanding of the physics is wrong."

    I cannot point to an email that shows that your understanding of the physics is wrong, but it has long been claimed by AGW scientists that "...the science is settled." This claim is used by policy-makers of many countries to promote drastic cap-&-trade-type measures that many see as draconian (if not outright totalitarian). Therefore, while I can't point to an email that shows that the physics is definitely wrong, I can certainly point out an email string that shows the physics is not settled, and indicates that it might be wrong.

    This exchange - - between Kevin Trenberth, Michael Mann, Tom Wigley, Stephen Schneider, and one of Schneider's PhD candidates (read from the bottom, up) certainly indicates that the physics of where the heat went in that past decade is not well understood.

    Trenberth writes, "...we can't account for the lack of warming at the moment and it is a travesty that we can't."

    Wigley responds, "I do not agree with this."

    Trenberth writes back, "How come you do not agree with a statement that says we are no where close to knowing where energy is going or whether clouds are changing to make the planet brighter. We are not close to balancing the energy budget. The fact that we can not account for what is happening in the climate system makes any consideration of geoengineering quite hopeless as we will never be able to tell if it is successful or not! It is a travesty!"

    Mann then tries to explain it in terms of natural variability: "...we can easily account for the observed surface cooling in terms of the natural variability seen in the CMIP3 ensemble (i.e. the observed cold dip falls well within it). So in that sense, we can "explain" it."

    But Mann is not that certain this is a full explanation, so he continues: "But this raises the interesting question, is there something going on here w/ the energy & radiation budget which is inconsistent with the modes of internal variability that leads to similar temporary cooling periods within the models. I'm not sure that this has been addressed--has it?"

    Trenberth responds with his concerns again: "Saying it is natural variability is not an explanation. What are the physical processes? Where did the heat go? We know there is a build up of ocean heat prior to El Nino, and a discharge (and sfc T warming) during late stages of El Nino, but is the observing system sufficient to track it? Quite aside from the changes in the ocean, we know there are major changes in the storm tracks and teleconnections with ENSO, and there is a LOT more rain on land during La Nina (more drought in El Nino), so how does the albedo change overall (changes in cloud)? At the very least the extra rain on land means a lot more heat goes into evaporation rather than raising temperatures, and so that keeps land temps down: and should generate cloud. But the resulting evaporative cooling means the heat goes into atmosphere and should be radiated to space: so we should be able to track it with CERES data. The CERES data are unfortunately wonting and so too are the cloud data. The ocean data are also lacking although some of that may be related to the ocean current changes and burying heat at depth where it is not picked up. If it is sequestered at depth then it comes back to haunt us later and so we should know about it."

    John, this is a very serious disagreement over the physics of planetary warming, or lack thereof over the last few years. It has the potential to profoundly impact policy-makers decisions. Can you explain the physics to Trenberth's satisfaction? Or to the satisfaction of the average layman - like myself - who is concerned about the social engineering being proposed based on this very physics?
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  43. Chris .... "New concepts in global tectonics" thought Ollier's paper worthy of publication and as you are no doubt aware, if you want to criticise it, you should address the science he puts forward .

    On the question of sea level rise, surely you would be concerned about Morner’s comments ( see my previous post ) that the IPCC adjusted sea level data “otherwise we would not have gotten any trend”. Or is that not relevant ?
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  44. "I've just completed Mike's Nature trick of adding in the real temps to each series for the last 20 years (ie from 1981 onwards) and from 1961 for Keith's to hide the decline."

    This isn't science, its arranging data to suit a pre- conceived agenda. And your stubborn refusal to acknowledge this, and the way you skip over this basic fact shows you are simply protecting the interests of your class-ie mainstream academia. This is a very common human trait, but it is not a scientific one.

    And its the very reason skeptics are so skeptical-its not about some 'nefarious conspiracy', its simply about human bias and the very common, but unscientific trait, of protecting ones social group/class interests. This is enough to distort data, and to allow it to go uncorrected/unregulated.

    Take a long hard look at what is being done in the above quote to the actual data, and just as importantly, to its presentation. A basic tenet of science is that the present is the key to the past. This is violated in the above 'trick', 'hiding', 'data handling techniques available in the peer reviewed literature' or whatever you want to call it. Fudging is fudging. The researchers choose to ignore the current, verifiable, tree ring data which shows the technique has major problems with the present, and yet use this same flawed technique to reconstruct the variable and dynamic climatic past, without due reference. They recognise, selectively, that the 'present' has a problem, and so they, conveniently, replace it with something else, but if they are to be consistent they shouldn't then be using the same, verifiably flawed technique, to reconstruct (ie 'arrange') the past. (He who controls history controls the future). This is a selective arrangement to suit ones pre-conceived agenda. They then further violate basic statistical presentation by splicing different datasets, and different methodologies, together, without proper referencing. Every one of these steps violates standard scientific principles. 'Data handling techniques available in the peer reviewed literature' my arse. It is misleading, at best, and wrong at worst, to present spliced data as a single dataset, especially if there are known and obvious flaws in any of the techniques used to obtain parts of the dataset, which are not then applied to the rest of the dataset, and not being properly referenced.

    Do you really think, that the Busang-like graph of Mann et al 1998 presented to the uniformed public (who are not aware of the splicing etc) does service to science? I don't. The point with the Busang fraud, was that they used spliced datasets which contained flawed collecting (salting) and analysing (eg non-duplicated) techniques within parts of the datasets, and then presented this as a single, coherant (pre-arranged outcome) dataset. This sort of 'hiding' and 'trick' and 'data handling technique available in the peer reviewed literature' cost billions of dollars. Sound familiar to Mann et al 1998?

    Applying the 'present as the key to the past' to the "suggestion of a change in the sensitivity of tree growth to temperature in recent decades" implies that tree ring growth during abnormally warmer periods is inhibited, therefore further implying a strong MWP which is not being picked up the tree ring proxies-which is the exact opposite to the conclusions of Mann et al 1998, (because he doesn't use this basic scientific tenet, he simply replaces it with a pre-conceived agenda).

    Moreover both the Wilmking and Briffa papers refer to the 'divergence problem' as real, not as a statistical methodological problem; they don't attempt to 'trick' 'hide' or substitute it with 'data handling techniques available in the peer reviewed literature' to get a pre-arranged outcome, but rather they seek to highlight the connotations of such a divergence (which as I said above, includes a stronger MWP).

    Your references to the 'physical realities currently being observed' doesn't change the central issue, whether or not these 'physical realities' are being caused by humans (AGW). Th reason the skeptics focus on eg reconstructions, is that this is one particularly sensitive piece of the puzzle which has a large say in whether humans are causing the current warming.

    I for one, can agree, with a shove and a push, that all your 'physical realities' may well be true, yet the issue of whether humans are causing them remains, and so we go back to eg Mann et al 1998 and his 'tricks' 'hiding' etc. I disagree therefore that such things are only a small piece of the puzzle.
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    Response: The divergence problem is not about obtaining a pre-conceived result - it's about compiling all the different pieces of the puzzle into a single, coherent picture.

    The divergence problem has no connection to the Medieval Warming Period - it is concerned with the last few decades of proxy records. But even if the MWP was much greater than currently thought, that would mean climate is more sensitive than currently thought - which means climate is more sensitive to the radiative forcing from CO2. This is the great irony in the skeptic obsession with the hockey stick. If climate scientists have been underestimating past climate change as skeptics claim, then the danger of CO2 warming is that much worse now.

    The "hockey stick" is not a particularly significant part of the evidence that humans are causing warming. It's suggestive, sure, that CO2 and temperature both show hockey stick like shapes. But correlation does not necessarily prove causation. The evidence that humans are causing global warming is found in observations of an enhanced greenhouse effect at CO2 wavelengths.

    If you can be pushed and shoved to agree that the physical realities (of accelerating ice loss in Antarctica, Greenland, glaciers, Arctic, etc) are actually happening, well, each journey begins with a single step. :-)
  45. @billbrent, 54
    "John, this is a very serious disagreement over the physics of planetary warming, or lack thereof over the last few years. It has the potential to profoundly impact policy-makers decisions. Can you explain the physics to Trenberth's satisfaction? Or to the satisfaction of the average layman - like myself - who is concerned about the social engineering being proposed based on this very physics? "

    Why don't you check the facts before jumping to conclusions? And with explanations easily available, your reference to and interpretation of the notorious "Mike's Nature trick" either shows an ignorance I would not expect from contributors to this site, or willfull misrepresentation.

    Just to make it clear: I do not defend their approach to the divergence problem in that case, in particular their presentation. But it's not fraud to proceed as they do. And it's not about the benefit of doubt here, the wording uses "trick" as in my favorite definition of "method": "A method is a trick that you use twice." Any attempt at a fair interpretation would show up this. And no, it is NOT a fair interpretation to pick one that implies malpractice without checking alternatives first, even if that one comes easily to mind.

    Then, to "very serious disagreement over the physics of planetary warming". You did check all the details before you make such a sweeping statement, didn't you? Oh no, then you wouldn't used that wording. First, the "balancing of the energy budget" is according to Trenberth's standards, and they are higher than average, to say the least. Second, this is mostly not about lack of physical understanding, but lack of data.

    The observations show that the models are not adequate, and they have to be improved. Which is not shocking unless you have had very much faith in the present incarnations of the models - and that may be the case with some in the general public. I'm concerned that the results may have been oversold.

    But the focus on this blog is on the science, and there is really nothing new or very problematic in what Trenberth is talking about. To get us where he wants may very well imply some methodological revolutions, but almost surely none of physics. To put it simple: The positive feedbacks, while still very significant, have been smaller than implied by the models, and now they are looking into why.

    Your concern about "social engineering" is valid. But to me, it's a bit the other way around: Increasing the GHG emissions as we do is a gigantic, for a large part non-reversible, experiment, and THAT should not be allowed unless we know the consequences fairly exactly, and there is global agreement that they are acceptable. We know, both from theory and observations, that anthropogenic global warming occurs, the question is about the extent. And, contrary to what many "skeptics" maintain, that question is not that relevant to decide about regulations of GHG emissions. Why? First, even with zero positive feedback, "carbon liberalism" will get us into climate problems pretty soon. Second, even with small temperature changes, CO2 emissions will, sooner or later, lead to catstrophic acidification of the oceans.

    I might add a third: Sooner or later, we have to get off the fossile fuel hook anyway. And why not sooner, when we, basically, already have the technology? But that's not something we should focus on here, I think.
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  46. re: divergence problem

    I don't see why people seem to have such a hard time understanding this issue. There is a variety of proxy data available as well as the instrumental record. There is no problem with omitting proxy data that deviates from observed results.
    If I have 10 clocks in my house and I notice that one of them starts working:
    1) I know that it is more likely that one clock is giving the wrong reading than the other 9 showing the same wrong reading.
    2) It would be silly to criticize me for not using the errant clock when its clearly wrong. It is neither devious nor underhanded to avoid the bad clock.

    I have to admit that I thought the CRU leak was going to be a big deal. After reading through it and reading the explanations given I am surprised that so little of substance can be used to criticize the team. I do think as a PR issue they should make a statement which will clear the air and also serve as a scary science lessen for those that think AGW is a hoax.
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  47. For me, what comes out of the hacked Hadcrut emails is that there is much disagreement between scientists about many aspects of climate research, particularly in the area of interpretation of proxy data. That is tree-rings, ice cores, lake sediments etc.

    One email states that it is generally considered by scientists that the effect of the solar cycle cannot be identified in the temperature record. The same scientist then does some research and comes to the conclusion himself that effect of the solar cycle can be identified in the temperature record.

    My point is that the emails show that there are large uncertainties in the field of climate research. But it seems we have not been told this. We are instead told that the science is settled. It is not !

    And now world governments want to spend hundreds of billions of dollars fighting this global warming (or is it climate change ? ) based on such shaky science.
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    Response: Certain key questions are settled. The warming effect from CO2 is known with high understanding and directly observed by satellites and surface measurements. The planet's energy imbalance is directly measured from ocean heat and satellites. There are other areas with higher uncertainty such as the radiative effects from aerosols or the behaviour of clouds as climate warms. When all the uncertainties are considered, climate scientists conclude that there is a greater than 90% chance that humans are causing global warming (I believe this actually understates the certainty).

    If you were told there was a greater than 90% chance that a plane was going to crash, would you get on board with your family? And yet this is the risk skeptics are happy to take with the planet we're handing over to our children and grandchildren.
  48. Regarding your response above, my reply is as follows :

    It is clear from some of the hacked Hadcrut emails that the climate research scientists agree that they do not understand why there is a lack of warming at present and that their computer models do not predict this lack of warming.

    There are also emails which state that when climate changes, it is often difficult to apportion the cause
    ( man-made, natural or some combination of the two. )

    Your statment above : "there is a greater than 90% chance that humans are causing global warming" is not correct is it ? It should read : "there is a greater than 90% chance that humans are having some effect on global warming - but natural forcings still play an important part"

    In any event, given the many factors that go into any estimate of probability in this case, I would not take the scientists 90% chance claim seriously in terms of a statistiacl probability. I believe that in the IPCC reports this probability is expressed as more of a "gut feel" rather than a statistically calculated probability. If all the uncertainties are taken into account, each with its associated confidence interval, I would be amazed if the result would be a 90% probability. If this 90% chance was based on a statistical calculation, do you have the complete data sets used as I would like to see them?

    Many (most ?) skeptics ( including myself ) are not anti AGW or anti environment. I would say that most (?) of us would agree that the temperature is rising in general and would agree that trying to curb toxic emmissions is good. What I cannot abide is the fact that the way of doing this ( carbon tax, possible " world government", passing billions of dollars over to third world countries etc ) is the wrong way. It is clear that this scenario would be based on very shaky science and one would have to be naive not to realise that such a decision would be motivated by wider political considerations.
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    Response: You're putting the horse before the cart. Carbon taxes and one world governments have nothing to do with climate science. The confusion and muddled thinking that occurs when politics are inserted into climate debates are the reason why this website is concerned with a single question - are we causing global warming? The answer to that question lies purely in the realm of science and empirical measurements. I would encourage you to clear your head of one world governments for the moment and consider what observed empirical data has to say about man's influence on climate.
  49. John,
    It is clear that skeptics are the badguys. But when they ask, "OK, so if CO2 is the culprit, what alternative do you propose? And what are the risks of these solutions?", all that you find on this website is the same churning about CO2, CO2, CO2. Where is the science that points to solutions and alternatives???

    Whether global warming is manmade or not should have no relevance if the alternatives are so attractive and have no "risks". Please explain.
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  50. To neilperth
    I seem to agree with every word you say. No changes.
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