The "97% consensus" on AGW is out of date...

[caraher]

If you measure by more recent peer-reviewed literature, you get a much different picture of the raging scientific controversy over climate change than Naomi Oreskes' dated analysis and other AGW "alarmist" claims suggest...

[LouisvilleDem]

1. Unfortunately this is meaningless

The way the study defined the term "rejected anthropogenic global warming", all of the well known skeptic scientists get categorized as non-skeptics. This and Oreskes' study use fundamentally flawed methodology. It's a shame really, because I think we need a list of people that deserve to be flogged when the deluge comes...

[caraher]

2. Go ahead and re-analyze the data then

The author provides an Excel file with all the papers - you need only go back through and flag those from the "well-known skeptic scientists" to come up with your list of those who need flogging.

Anyone can repeat as much of the new study as they wish--all of it if they like. Download an Excel database of the 2,258 articles here. It includes the title, document number, and Web of Science accession number. Scan the titles to identify articles that might reject man-made global warming. Then use the DOI or WoS accession number to find and read the abstracts of those articles, and where necessary, the entire article. If you find any candidates that I missed, please email me here.

[LouisvilleDem]

6. Ommisions

I started to do this and discovered there are a huge number of papers this study missed. I was familiar with the fact that there have been a number of studies published recently that claim that climate sensitivity is much lower than what the IPCC claims. Needless to say, I personally believe that these studies are junk science written by skeptics. So I downloaded the Excel database and searched for papers with the words 'Climate Sensitivity' in the title. After a reading a few of the articles that I found by googling the DOI number, I ended up reading a paper on the American Meteorlogical Society website. While there, I noticed a search facility on the sidebar that would let me search for AMS journal articles with 'Climate Sensitivity' in the title. I figured, great, instead of flipping back and forth between the Excel spreadsheet, doing a google search and finding the article, I can just stay on the AMS site and save myself a bunch of time. After all, any article about climate sensitivity has got to have been included in the study's 2258 articles. Bzzzz. Wrong. A quick comparison revealed that 15 of the 17 articles with Climate Sensitivity in the title did not show up in Powell's list. If his methodology missed that many articles using just one specific aspect of climate change (climate sensitivity) in just one specific journal (AMS), its hard to believe his sample is representative.

I'll email this to the author and see what happens.

You can verify by searching the AMS website yourself if you'd like:

http://journals.ametsoc.org/action/doSearch?type=advanced&displaySummary=true&author=&title=Climate+sensitivity&searchText=&abstract=&pubidspan=&categoryId=allJournals&filter=multiple&start=2012-11-12&end=2013-12-31&Search=Search&startPage=0&captionspan=&fulltext=&notes=&sortBy=date&pageSize=20

[kristopher]

3. Do me a favor and back that up with the specific language you are referring to.

[LouisvilleDem]

4. Here you go

http://www.jamespowell.org/methodology/method.html

Basically he does a search to obtain a set of journal articles that are about climate change and then for each one:

Read some combination of titles, abstracts, and entire papers as necessary to judge whether a paper "rejects" human-caused global warming or professes to have a better explanation of observations.

Richard Lindzen, one of the best known skeptics (http://www.skepticalscience.com/lindzen-illusion-7-the-anti-galileo.html), pointed out that by this definition (he was actually referring to the original Oreskes study) none of his papers met the study's definition of "rejecting human caused global warming". This is because he agrees that the world is warming and that CO2 is part of the reason it is warming. The fact that he also believes there won't be enough warming to make it something we need to worry about is apparently not enough to make him a skeptic.

[caraher]

8. I don't think Lindzen has any peer-reviewed publications in the relevant time frame

His own publication list web page is clearly out of date (it lists nothing after 2011). Still, I only found one paper in 2012.

I do agree that the selection criteria can skew the count substantially. At least Powell is transparent about how he got his numbers.

[LouisvilleDem]

13. Transparent yes

Repeatable no. Any "study" whose results cannot be replicated by other scientists is not really science.

[caraher]

14. What's unrepeatable about it?

Disagree with the methodology all you like, but it's perfectly repeatable. You can change the criteria and get different results, but that just makes it a new "experiment," that you are free to argue is superior to his. Powell insists that his results are perfectly replicable if you repeat what he did. If you do a slightly different scientific experiment, you actually should generally expect a different result, not the same one.

But what if I had used different search terms? Another article that I allegedly missed provides the answer:

European hot summers associated with a reduction of cloudiness

This article does not have global warming or global climate change as keywords, nor does either term appear in the abstract. Nor do I believe that it rejects man-made global warming using my criteria, but that is not the point here.

The keywords from the WoS are: SOIL-MOISTURE; HEAT WAVES; SURFACE-TEMPERATURE; SOLAR-RADIATION; CLIMATE-CHANGE; PRECIPITATION; IMPACT; FEEDBACK; CLOUDS; TRENDS

To find this article, I would have had to use one of those terms. Had I used “climate change” as a keyword, from 1991 to the present the search would have turned up this paper, and 62,662 additional articles. Is there any reason to suspect that a greater proportion of those 62,662 articles would have rejected man-made global warming? Let anyone who believes the answer is yes have at it.

It's hard to imagine that any reasonable variation on what he did will result in the emergence of a significant number of "skeptical" publications in the peer-reviewed literature, and that's the real point. Add "climate sensitivity" to the search terms and then tally up the papers that appear to be skeptical of AGW. You will, of course, get different numbers, but you are also not repeating what he did. More importantly, you are not going to suddenly find a lot of "skepticism" emerge from the new tally.

[LouisvilleDem]

15. The definitions are too subjective

This is the weak step in the process:

Read some combination of titles, abstracts, and entire papers as necessary to judge whether a paper "rejects" human-caused global warming or professes to have a better explanation of observations.

Two different people can read the same paper and come to different conclusions regarding whether or not the paper "rejects" human-caused global warming. An example of this very thing can be found on this thread. A more proper study would define a very precise criteria for what constitutes "rejection" of global warming. For example, in drawing up a list of skeptical scientists, Wikipedia defines the following:

The main conclusions on global warming were as follows:

The global average surface temperature has risen 0.6 ± 0.2 °C since the late 19th century, and 0.17 °C per decade in the last 30 years.

"There is new and stronger evidence that most of the warming observed over the last 50 years is attributable to human activities", in particular emissions of the greenhouse gases carbon dioxide and methane.

If greenhouse gas emissions continue the warming will also continue, with temperatures projected to increase by 1.4 °C to 5.8 °C between 1990 and 2100. Accompanying this temperature increase will be increases in some types of extreme weather and a projected sea level rise. The balance of impacts of global warming become significantly negative at larger values of warming.

In their methodology, a person that disagrees with one of the above statements should be considered a skeptic. You can disagree with their criteria, but that is not my point. The point is that they define their terms much more precisely and therefore are less likely to suffer from subjective differences.

[caraher]

16. OK, but this is a shift

Your initial objection was that the search excludes articles that should be considered; now it is that the "coding" is subjective.

Using his search terms, then, if the classification is the weak link, there should be authors from his 2000+ articles stepping forward to say they were wrongly classified as not skeptical. Or at least people identifying additional papers from his list that are mischaracterized.

Both are perfectly reasonable objections, but I still don't see how either or both would materially change the conclusions (though they could change the exact numbers, of course).

[LouisvilleDem]

17. An additional problem, not a shift

Simply put there are lots of things wrong with this study. It would never get published in a reputable journal.

[LouisvilleDem]

5. A specific example

Take a look at this paper, written in 2013:

"Overestimated global warming over the past 20 years"

http://www.nature.com/nclimate/journal/v3/n9/full/nclimate1972.html

Do you believe this paper should be considered 'skeptical'?

[caraher]

7. Not really

There's not a hint that the authors are skeptical about human-caused warming. They argue for a need to improve the modeling. Here is the abstract:

Recent observed global warming is significantly less than that simulated by climate models. This difference might be explained by some combination of errors in external forcing, model response and internal climate variability.

(I've also found a copy of the paper not behind a paywall...)

This in no way argues that warming is not human-caused or is not significant.

I'm also not sure whether "Commentary" pieces are peer-reviewed, which would also remove it from the list.

[LouisvilleDem]

9. It is a matter of opinion I guess

On average, I believe current models predict 2.1C of warming over the next century. By saying that models 'significantly' overestimate warming the authors are basically adopting a lukewarmer position. I personally think lukewarmers are so close to deniers that the distinction is irrelevant, and I've heard through the grapevine that expressing that exact same position has gotten several people banned from this very forum (AverageJoe90 was the person I think they were talking about).

Personally, I like the way Wikipedia categorizes scientists. It is far more nuanced:

http://en.wikipedia.org/wiki/List_of_scientists_opposing_the_mainstream_scientific_assessment_of_global_warming

[kristopher]

10. No, I don't.

The question is why do you?

Caraher has addressed your statements well so I'll move onto a more personal note. You were attacked by a couple of regular posters here for attempting to frame denialist arguments about the climate change significance of extreme weather events.

I defended you in that case because your point was true when narrowly viewed and charitably read.

I was wrong to do so.

[LouisvilleDem]

11. Consensus View

The whole job of the IPCC is to review the existing body of scientific research and determine the current consensus view as we best know it. All of my extreme weather views were consistent with what the IPCC said in AR5--the people who attacked me for expressing them were just ignorant of what the consensus science said. In contrast, the IPCC has consistently maintained that climate sensitivity is probably around 3C and not lower than 2C. In my mind, anybody who tries to undermine the validity of the computer models is a denier, and a particularly dangerous one at that. Everything we know that is dangerous about climate change comes from model predictions. Undermine the models and you undermine the entire explanation of why we need to take drastic action ASAP.

[kristopher]

12. Sure, yeah. You're a persecuted saint.

G'bye.