Bad study on climate experts opinion

[Oberon]

I started commenting on this study in another thread, but it was off topic. So I'm re-posting here, mainly because another poster claimed my comments were factually incorrect. Rather than continue to derail the thread, here's the study:Expert credibility in climate change — PNAS

It is a clear attempt to enhance the credibility of AGW theory by noting that virtually all the real experts by into it. While it is very likely true that most experts do, this study is very poor and misrepresents the number of skeptics among experts. Here's my post:

This is exactly why the term "poll" is problematic. They didn't go around asking what people believed. In fact, they didn't ask anybody anything. What they did was compile a list of over a thousand experts designed to already sort the experts into categories (read their methods sections). There are several problems here:
1) As already noted, this method could very easily mean placing skeptics in the "convinced by the evidence" group. Again, Dr. John Christy is among the foremost authorities on climate change, which was why he was asked to contribute to working group 1 by the IPCC. The problem is, his contribution to AR4 gets him sorted into the "convinced" crowd, when he isn't
2) The methods they used to get their list of names meant limiting themselves only to those scientists who have publicily come out and signed some list or joined some group, a method which got them almost twice as many people in the CE camp. It isn't a great way to assess the field, because there may be many published scientists who haven't sciened something like the oregon petition.
3) Here's the kicker: they then cut these two groups down to 817 to 93 and using google scholar they determined who were the "top" researchers. They did this not just by noting how much a given scientist was published, but how much they were cited. The problem is, guys like Mann, Jones, etc, all cite each other all the time. As the authors admit "our dataset is not comprehensive of the climate community." Their methods predetermined their result. Unbelievable.
4) Finally, the one problem with ranking based on publications is that many skeptical experts find their funding dropped and their studies rejected, compared with the ease other experts get published (e.g. Mann still gets his studies published despite using proxies the NAS said were unreliable). The CRU emails show that there are gatekeepers to publication which limits the amount skeptics get published.

There are better studies which show that a substantial majority of experts believe humans are causing an increase in temperature. This certainly doesn't show that 97% of climate scientists believe in AGW. In fact, they found several hundred scientists who do whom they excluded from the study.

 

[Alceste]

Factual error number 1: Dr. John Christy

I quote: "As far as the AGU, I thought that was a fine statement because it did not put forth a magnitude of the warming. We just said that human effects have a warming influence, and that's certainly true."

Sounds pretty convinced to me.

Factual error number 2: CRU emails and the AGW conspiracy theory

Several inquiries have exonerated the authors of the CRU emails of any wrongdoing, conspiracy or professional malpractice apart from failing to respond to FOI requests by climate change deniers in a timely fashion.

Factual error number 3: Skeptics were excluded by design.

Many skeptics were self-excluded because they have not published more than 20 papers. This is a neutral threshold could have excluded anybody, as was the tallying of citations. On the other hand, though it might frustrate you to accept this, publications and citations are in fact a completely valid gauge of a scientist's prominence and credibility. Even if there is, as you insinuate, a vast conspiracy to exclude reality-deniers like climate skeptics and creation scientists from mainstream publications, this in itself would constitute excellent evidence that the majority of scientists accept the mainstream view.

How about you provide an equally credible study that calls their findings into question?

 

[Oberon]

Factual error number 1: Dr. John Christy

I quote: "As far as the AGU, I thought that was a fine statement because it did not put forth a magnitude of the warming. We just said that human effects have a warming influence, and that's certainly true."

Sounds pretty convinced to me.

Then you didn't read carefully. Most of the skeptics believe that CO2 will cause some warming. What they don't agree with is that this will be a problem. I corresponded with Christy personally. He does not believe we know enough to say that AGW is a problem. You can read all about in his letter protesting the EPA's proposed rules on CO2 here. Also, since you like wikipedia: "I'm sure the majority (but not all) of my IPCC colleagues cringe when I say this, but I see neither the developing catastrophe nor the smoking gun proving that human activity is to blame for most of the warming we see. Rather, I see a reliance on climate models (useful but never "proof") and the coincidence that changes in carbon dioxide and global temperatures have loose similarity over time." Source

Factual error number 2: CRU emails and the AGW conspiracy theory

Several inquiries have exonerated the authors of the CRU emails of any wrongdoing, conspiracy or professional malpractice apart from failing to respond to FOI requests by climate change deniers in a timely fashion.

I am aware of the hearings, and aware of the fact that none of them actually addressed the hard questions. However, that goes beyond the scope of this debate. I have no problem getting into it, but it isn't necessary for my point here. If you want to go into detail on how these inquiries failed let me know.

Factual error number 3: Skeptics were excluded by design.

Many skeptics were self-excluded because they have not published more than 20 papers.

Wrong. You don't seem to understand how they picked the skeptics. They didn't look at the research and then determine who was a skeptic. They picked skeptics based on who has signed petitions. This excludes any scientists who didn't feel like they wanted to go public with their views. Not everyone is in a position where they can do so, and not everyone wants to. It is a basic fact of study procedure that your selection methods determine in part your results. This is why randomized selection is so important. You want your sample to be representative of the population. By selecting the most outspoken, you have biased your sample.

How about you provide an equally credible study that calls their findings into question?

I don't have to. Their methods make that clear. Hell, their own statement is pretty clear "Our dataset is not comprehensive of the climate community and therefore does not infer absolute numbers or proportions of all CE versus all UE researchers." This is particularly true when there methods get UE scientists in the CE group, and considering their selection process.

 

[dmgdnooc]

OK, so add in the missing skeptical scientists. What do we come up with?
96% of scientists acknowledge that anthropogenic CO2 is driving climate change,
95 or 94% maybe, certainly not less than 90%.
　
Its all moot, a done deal long ago.
　
From the Vienna Convention for the Protection of the Ozone Layer (1988)
http://www.austlii.edu.au/au/other/dfat/treaties/1988/26.html
　
Preamble - '... States have .... the responsibility to ensure that activities within their jurisdiction or control do not cause damage to the environment of other States or of areas beyond the limits of national jurisdiction.'
　
Article 2.1 'The parties shall take appropriate measures .... to protect human health against adverse effects resulting or likely to result from human activities which modify or are likely to modify the ozone layer.'
　
Annex 1.4.a 'Carbon Dioxide .... affects stratospheric ozone by influencing the thermal structure of the atmosphere.'
　
The signatories to this Convention have already acknowledged their responsibility to not export their pollution. They have agreed to take appropriate action to protect human health. And they have recognised that CO2 levels influence the thermal structure of the atmosphere.
　
20 odd years ago those signatory States agreed to address these issues.
The question is - is your State a signatory to this convention?
　
If it is then it is being every bit as criminally negligent of its agreements as the Australian government.

 

[Oberon]

OK, so add in the missing skeptical scientists. What do we come up with?
96% of scientists acknowledge that anthropogenic CO2 is driving climate change,
95 or 94% maybe, certainly not less than 90%.

Where do you get these numbers? Prior to cutting down their lists based on recent publications and work, the authors of the above study found 903 in support versus 472 against. Of course, my whole point here is that these numbers are rather meaningless, but I would be interested in knowing where your numbers come from.

　

Its all moot, a done deal long ago.

I didn't open this to start a debate about climate change. If you would like to do that, I'm more than happy to, but this thread was to address the shortcomings of this particular study.

 

[dmgdnooc]

From the page you cited.
'(i) 97-98% of the climate researchers most actively publishing in the field surveyed here support the tenets of ACC (anthropogenic climate change) ..., and (ii) the relative climate expertise and scientific prominence of the researchers unconvinced of ACC are substantially below that of the convinced researchers.'
　
There may be flaws in how the number 97-98 was derived but they will not greatly alter the 'striking agreement among climate scientists on the tenets of anthropogenic climate change'.
　
The funders of this (uncriticised) critique have no doubt that ACC is a fact. The critique has not shaken their conviction of ACC, I see no reason that it should shake mine.
The William and Flora Hewlett Foundation have stated one of their goals is to 'Slow global climate change by reducing greenhouse gas emissions'.
Environment Program | Hewlett Foundation
Stanford University has no doubt that ACC is a fact. 'Carbon Dioxide is a major cause of global warming.'
Storing CO2 underground could shake up the Earth | School of Earth Sciences
　
I'm not interested in a debate on global warming.
My problem with such a debate is that we have had that debate already in the years leading up to the Vienna Convention.
My point is that governments all over the globe have already acknowledged that anthropogenic CO2 levels influence the thermal structure of the atmosphere.
End of story from my pov, the fact was legally recognised over 20 years ago.

 

[Oberon]

There may be flaws in how the number 97-98 was derived but they will not greatly alter the 'striking agreement among climate scientists on the tenets of anthropogenic climate change'.

That's the question, isn't it? How can you possibly know the magnatidue of the error?
　
The funders of this (uncriticised) critique have no doubt that ACC is a fact. The critique has not shaken their conviction of ACC, I see no reason that it should shake mine.
The William and Flora Hewlett Foundation have stated one of their goals is to 'Slow global climate change by reducing greenhouse gas emissions'.
Environment Program | Hewlett Foundation
Stanford University has no doubt that ACC is a fact. 'Carbon Dioxide is a major cause of global warming.'
Storing CO2 underground could shake up the Earth | School of Earth Sciences
　

My point is that governments all over the globe have already acknowledged that

anthropogenic CO2 levels influence the thermal structure of the atmosphere.

But has the science? and to what degree? What is global warming

 

[Alceste]

Then you didn't read carefully. Most of the skeptics believe that CO2 will cause some warming. What they don't agree with is that this will be a problem. I corresponded with Christy personally. He does not believe we know enough to say that AGW is a problem. You can read all about in his letter protesting the EPA's proposed rules on CO2 here. Also, since you like wikipedia: "I'm sure the majority (but not all) of my IPCC colleagues cringe when I say this, but I see neither the developing catastrophe nor the smoking gun proving that human activity is to blame for most of the warming we see. Rather, I see a reliance on climate models (useful but never "proof") and the coincidence that changes in carbon dioxide and global temperatures have loose similarity over time." Source




I am aware of the hearings, and aware of the fact that none of them actually addressed the hard questions. However, that goes beyond the scope of this debate. I have no problem getting into it, but it isn't necessary for my point here. If you want to go into detail on how these inquiries failed let me know.



Wrong. You don't seem to understand how they picked the skeptics. They didn't look at the research and then determine who was a skeptic. They picked skeptics based on who has signed petitions. This excludes any scientists who didn't feel like they wanted to go public with their views. Not everyone is in a position where they can do so, and not everyone wants to. It is a basic fact of study procedure that your selection methods determine in part your results. This is why randomized selection is so important. You want your sample to be representative of the population. By selecting the most outspoken, you have biased your sample.



I don't have to. Their methods make that clear. Hell, their own statement is pretty clear "Our dataset is not comprehensive of the climate community and therefore does not infer absolute numbers or proportions of all CE versus all UE researchers." This is particularly true when there methods get UE scientists in the CE group, and considering their selection process.

Christy believes human activities have contributed to global warming. That is the only factor this study attempted to quantify. Case closed.

You spend a lot of time picking apart research for not accomplishing things it did not set out to do. Is that fun for you?

 

[dmgdnooc]

ACC is not 'rocket' science, its 19th century long established fact.
CO2 is a 'greenhouse' gas the science at the root of global warming is as complex as 'greenhouse' science.
When CO2 is introduced into an atmosphere that atmosphere will retain more of its heat.
　
Human activity introduces CO2 into the Earth's atmosphere and impacts on the Earth's climate systems.
Governments the world over acknowledged this fact by signing the Vienna Convention and undertook to take appropriate measures to protect humanity from any adverse effects resulting from this human activity.
And the adverse effects did not have to be 'slam dunk' 100% proven certainties, there only has to be a likelihood of adverse effects.
It was further agreed that States have no right to undertake activities that cause damage to the environment of other States.

This deal is done, the ink is long dried and its too late to renegotiate.

 

[Oberon]

Christy believes human activities have contributed to global warming. That is the only factor this study attempted to quantify.

Nice try. Try reading the study. It is about agreement with the IPCC. From the opening: "anthropogenic greenhouse gases have been responsible for “most” of the “unequivocal” warming of the Earth's average global temperature over the second half of the 20th century. According to the study, the difference is not those who believe that there is some warming humans contributed to, or none, but whether or not they agre with the IPCC version: "A vocal minority of researchers and other critics contest the conclusions of the mainstream scientific assessment"

This can also be seen by examing some prominent names on their lists of those unconvinced. Signers included on some of these lists include researchers like Patrick Michaels, who also believes humans are causing a warming but that it isn't a problem.

So no, according to the study, isn't just about whether there was any human caused warming at all, and there methods wouldn't select people into those groups (as many signers of their UE documents disagree with the IPCC only in that the human caused warming isn't a problem), because the point of the study was agreement with the mainstream (IPCC) version of ACC. Christy isn't in agreement, but was sorted into this group thanks to being a contributer working group 1.

Nice try.

You spend a lot of time picking apart research for not accomplishing things it did not set out to do. Is that fun for you?

Actually what's a lot more fun is to see your claims fall apart. If you were correct, and these researchers merely wanted to get a sense of which experts believed humans were responsible for any warming, then there methods were just as flawed. Most skeptics acknowledge that humans are likely causing some warning, just that it isn't a problem. In this case, there method of obtaining UE members is flawed, and the study is meaningless, because nobody cares about global warming if it isn't a problem. For example, the common (i.e. IPCC) estimates of warming caused by CO2 alone are not an issue. Only with the feedback parameters does climate change become concerning, and it is this feedback that the debate is about. Not whether humans are causing any warming at all.

 

[Alceste]

Oberon, still waiting for your equally credible counter-evidence. I'm not the type to dissect the limitations of any research published by a credible institution unless I am looking at two equally credible but conflicting findings. Or unless I, like you, have an irrational personal attachment to an ideology the bulk of the available research calls into question, but that type of situation is infrequent for an apophatic.

 

[Oberon]

Oberon, still waiting for your equally credible counter-evidence.

The study was just published, this year. If someone wants to critique the paper in the peer-review (and is allowed to publish) one would hardly expect it to be published by now unless an opposing view was asked for from the beginning. Sciencemag has a could unbaised view of the paper though, noting both strengths and weaknesses:"
But the paper, published todayin the Proceedings of the National Academy of Sciences, faces criticism on three fronts: how it divides scientists into one of two groups, whether the scientists have been chosen properly, and whether the peer review process stacks the deck in favor of the consensus view. "This is a completely unconvincing analysis," says climate expert Judith Curry of the Georgia Institute of Technology, who was included in neither group. "

Scientists 'Convinced' of Climate Consensus More Prominent Than Opponents, Says Paper - ScienceInsider

I'm not the type to dissect the limitations of any research published by a credible institution

That's a rather interesting take. So unless you are spoon fed information you don't have the capability to assess basic methodological problems? Well, thankfully, I don't suffer from that limitation. I have taken a variety of research methods courses and studied statistics. I also know how they sorted their groups and have pointed out the problems with this approach. Other scholars have done the same.

Comments On The PNAS Article “Expert Credibility In Climate Change” By Anderegg Et Al 2010 | Climate Science: Roger Pielke Sr.

Or unless I, like you, have an irrational personal attachment to an ideology

You do. If I put up a study showing something you didn't like, I have no doubt you'd try to take it apart. In fact, in the past when I have posted peer-reviewed information by scientists you have made ad hominem attacks.

 

[Alceste]

The study was just published, this year. If someone wants to critique the paper in the peer-review (and is allowed to publish) one would hardly expect it to be published by now unless an opposing view was asked for from the beginning. Sciencemag has a could unbaised view of the paper though, noting both strengths and weaknesses:"
But the paper, published todayin the Proceedings of the National Academy of Sciences, faces criticism on three fronts: how it divides scientists into one of two groups, whether the scientists have been chosen properly, and whether the peer review process stacks the deck in favor of the consensus view. "This is a completely unconvincing analysis," says climate expert Judith Curry of the Georgia Institute of Technology, who was included in neither group. "

Scientists 'Convinced' of Climate Consensus More Prominent Than Opponents, Says Paper - ScienceInsider

I'm not looking for evidence that this study has flaws - every study has flaws. I'm asking you to supply counter-evidence that indicates these flaws have caused incorrect conclusions to be drawn. One way to do that would be to produce an equally credible published study that draws a completely different conclusion, for example that expert opinion is evenly divided or that experts on both "sides" are equally prominent and credible.

We both know you can't do that, so why don't you just tip your king?

That's a rather interesting take. So unless you are spoon fed information you don't have the capability to assess basic methodological problems?

No, unless I have very good reason to doubt the consensus of the vast majority of experts in any given field, I simply take it at face value.

Unlike you, I am not passionately driven to try to find fault with the methods of experts simply because - and only when - they conflict with my ideology. Every study has flaws. Unless you have a better designed, equally credible study at the ready that reaches a significantly different conclusion and are prepared to compare the merits and failings of both, from my perspective you're simply making noise for the sake of making noise.

If I put up a study showing something you didn't like, I have no doubt you'd try to take it apart. In fact, in the past when I have posted peer-reviewed information by scientists you have made ad hominem attacks.

You must have me mistaken for someone else. I do quite regularly point out when reality-denying research is directly funded by the PR industry on behalf of energy concerns. That's evidence of a conflict of interest, not an ad hominem attack.

Anyway, as I mentioned might happen at the start of this diversion, I'm already bored. It's quite clear you - much like creationists and 9-11 conspiracy theorists - have no empirical evidence to support your reality-denying position, so I'm going to clock out now.

Take it easy.

 

[Oberon]

. I'm asking you to supply counter-evidence that indicates these flaws have caused incorrect conclusions to be drawn.

One point would be that in order to get their numbers they discounted the opnion of over 300 scientists on the unconvinced side.

One way to do that would be to produce an equally credible published study

Only a more recent study hasn't been published yet. It takes a very long time for that to happen (this study was submitted in 2009 and not published until july of 2010). So I'll let you know. In the meantime, your point that "every study has flaws" is meaningless. There are minor flaws which cannot make a large difference, and there are major methodological errors. Selecting a biased non-random sample, and using a selection method that puts the wrong people in the wrong groups, is a major problem. There simply isn't any reason to take anything in the study seriously at all, unless of course you are only out to promote your own ideology.

We both know you can't do that, so why don't you just tip your king?

I could provide earlier studies, but would you discount them because they were earlier?

No, unless I have very good reason to doubt the consensus of the vast majority of experts in any given field, I simply take it at face value.

This isn't about the consensus for global warming. It is about clear and obvious methodological issues with this study. By the way, the consensus method for research across fields is that large, randomly obtained samples from the population you wish to study is the way to go, and that selecting based on other methods, especially ones like the authors' did, biases your samples.

So if you follow scientific consensus with respect to research methods, then you would discount this study.

Unlike you, I am not passionately driven to try to find fault with the methods of experts simply because - and only when - they conflict with my ideology. Every study has flaws.

I don't have a problem with a study that shows that most experts in the field agree that humans are causing a warming and that it is a problem. I suspect that is absolutely true. It isn't the conclusions of the study I have a problem with, it's the methods.

Because I don't base my opinion on climate change on what experts are saying, but on the studies and the science.

from my perspective you're simply making noise for the sake of making noise.

Right. Because the only possible way a study could have serious methodological problems is if another study contradicts it, even though the first was published this year.

I do quite regularly point out when reality-denying research is directly funded by the PR industry on behalf of energy concerns. That's evidence of a conflict of interest, not an ad hominem attack.

It's quite clear you - much like creationists and 9-11 conspiracy theorists - have no empirical evidence to support your reality-denying position,

About climate change or this study? I have already discussed the issues with this study. As for climate change, I can cite plenty of article. But I'm sure that, rather than even bother to read them or try to critique them, you'd just discount them because your mind is already made up without doing the research.

 

[Alceste]

Don't see any links, didn't read.