Your peer review study is flaw and have been debunked! Here why James Powell is wrong !! Here is why is peer reviewed articles have major flaws!,
https://critical-angle.net/2016/04/04/james-powell-is-wrong-about-the-99-99-agw-consensus/
James Powell is wrong about the 99.99% AGW consensus
In a recent article in Skeptical Inquirer, geologist and writer James Lawrence Powell, claims that there is a 99.99% scientific consensus on Anthropogenic Global Warming (AGW). You might think that after all of the harsh criticism that the 2013 Cook et al. paper (C13) has received from climate contrarians that we would be pleased to embrace the results of a critique that claims we were far too conservative in assessing the consensus. While it certainly does make a nice change from the usual rants and overblown methodological nit-picks from the contrarians, Powell is wrong to claim such a very high degree of agreement.
He makes many of the same errors that contrarian critics make: ignoring the papers self-rated by the original authors; and making unwarranted assumptions about what the “no-position” abstracts and papers mean.
Powell’s methodology was to search the Web of Science to review abstracts from 2013 and 2014. He added the search term “climate change” to the terms “global climate change” and “global warming” that were used by C13. He examined 24,210 papers co-authored by 69,406 scientists and found only five papers written by four authors that explicitly reject AGW. Assuming the rest of the abstracts endorsed AGW, this gives consensus figures of 99.98% (by abstract) and 99.99% (by author).
His definition of explicit rejection would align roughly with the seventh level of endorsement used in C13: “Explicitly states that humans are causing less than half of global warming” . In the abstracts from 1991-2011, C13 found 9 out of 11,914 that fit level 7, which using Powell’s consensus calculation assumptions, would yield 99.92%. So, there is probably not much difference between the two approaches when it comes to identifying an outright rejection paper. It’s what you assume the other abstracts say—or do not say—that is the problem.
C13 also counted as “reject AGW” abstracts that: “Implies humans have had a minimal impact on global warming without saying so explicitly, e.g., proposing a natural mechanism is the main cause of global warming”. These are more numerous than the explicit rejections and include papers by scientists who consider that natural causes are more important than human causes in recent warming, but who do not outright reject some small human contribution.
pacmen2
Competing Climate Consensus Pacmen. Cook on the left, Powell on the right.
Perhaps the simplest argument that shows that Powell is wrong is that surveys conducted in the past ten years consistently show a stubborn, small minority of scientists who dismiss the mainstream expert view on AGW. These studies include polls of scientists, analyses of the published literature and examination of the public statements of scientists (see the references below). In a new paper that is currently in press we found that consensus increases with the degree of climate science expertise of the populations studied. When the studies are limited to publishing climatologists, the consensus ranges from 84- 98%. The specific criteria chosen for what constitutes endorsement or rejection of the consensus also influences outcomes.
There are a few scientists—and even a very few who actively publish in the peer-reviewed literature on climatology—who reject or play down the human role in recent climate change. In the second part of the C13 paper, we asked the authors of the articles whose abstracts we had analyzed to rate their own papers. We received self-ratings on 2141 papers, among which 39 (1.8%) were self-rated as rejecting AGW. Of the 1189 authors who responded, 28 (2.4%) wrote papers that rejected AGW to some degree or other. The dissenters are but a small percentage of the many thousands of scientists working on climate change. They may or may not be doing good science, but it would be foolish to deny that they exist.
The no-position abstracts and papers
Powell’s main beef is that we ruled out of the calculation of consensus the two-thirds of the abstracts that did not take a position on AGW. Since the analysis of the abstracts was limited to the text, we could not guess what the non-expressed opinions of the authors were. Powell:
[James] Hansen had a total of six articles in Cook et al.’s “no position” category. A number of other prominent climate scientists show up there as well. These include (with the number of articles): R. Bradley (3), K. Briffa (2), E. Cook (5), M. Hughes (2), P. Jones (3), T. Karl (5), M. Mann (2), M. Oppenheimer (3), B. Santer (2), G. Schmidt (3), the late S. Schneider (3), S. Solomon (5), K. Trenberth (7), and T. Wigley (3). Cook et al. ruled them all out of the consensus calculation.
It is maybe worth noting that the fact that we classified abstracts by many prominent mainstream climate scientists as “no-position” rebuts the notion that we regularly cheated by looking up the authors of the abstracts and classifying them accordingly.
Powell continues: (with my emphasis)
Most of these authors, like Hansen, also have articles in one or more of the three endorsing categories. Again, we see that the Cook et al. method is about language and the subject of articles rather than whether their authors accept AGW.
Bingo. It wasn’t an opinion poll and we didn’t try to guess what the authors think about AGW generally, we just relied on their specific abstracts. [Edited for clarity]
Many papers on the impacts of global climate change did not mention a human cause. A good number of papers on impacts looked only at local or regional—not global—climatic change. The majority of the paleo-climate papers did not mention the modern era at all.
By assuming that “no-position” abstracts or papers are tacit endorsements, Powell makes the same error that contrarian critics make when they claim that the “no positions” count as rejections or don’t-knows. By making such assumptions you either end up with results that the consensus is implausibly large or absurdly small.
Powell, arguing from personal incredulity:
Since it is inconceivable that any climate scientist today could have no opinion on the subject, if 97 percent accept AGW it follows that 3 percent reject it.
Studies like Doran and Zimmerman (2009) and Verheggen et al (2014) do actually get a few “don’t know” answers from samples identified as climate scientists. Some of these “don’t knows” may in fact be “can’t say” answers to questions that the scientists think were poorly framed. But it is surely likely that, in a sample of scientists that contains a minority that outright denies the major human influence on climate, there may also be a few who are genuinely uncertain about it.
Powell:
A scientist who has evidence that AGW is false will be eager to say so and to present that evidence. Who among us would not love to be that scientist!
This is a valid point. Mainstream scientists will be inclined to reserve the limited space of their abstracts for reporting novel results, therefore, statements of the obvious (endorsement of the consensus) may well go unmentioned. On the other hand, a result that goes against the grain of the consensus is, by definition, a novel result and is more likely to be explicitly reported. The C13 methodology, therefore, may well have systematically overestimated the relative level of rejection of AGW. (There was at least one exception to this, though, see the Footnote.)
To be continued on next post below:
