For anyone interested in the consensus on climate change, there’s a very interesting feature by Joseph Romm who blogs over on Climate Progress on Salon today, in which he argues that opinion on the cause of global warming is irrelevant. What is relevant, says Romm, is the overwhelming body of well-tested science and real-word observations.
Romm makes the case that the perpetual use of the word ‘consensus’ by the media, scientific community, and others mistakenly frames climate change as an issue of opinion, rather than one of scientific scrutiny based on data and evidence:
“Science doesn’t work by consensus of opinion. Science is in many respects the exact opposite of decision by consensus…One of the most serious results of the overuse of the term “consensus” in the public discussion of global warming is that it creates a simple strategy for doubters to confuse the public, the press and politicians: Simply come up with as long a list as you can of scientists who dispute the theory. After all, such disagreement is prima facie proof that no consensus of opinion exists.
So we end up with the absurd but pointless spectacle of the leading denier in the U.S. Senate, James Inhofe, R-Okla., who recently put out a list of more than 400 names of supposedly “prominent scientists” who supposedly “recently voiced significant objections to major aspects of the so-called ‘consensus’ on man-made global warming.”
Opinion polls on the climate consensus crop up from time to time. Coincidentally one such poll came to my attention this week, via email, and is being discussed over on Roger Pielke Sr’s blog.
The posts basically describe the rejection, first by the AGU journal EOS and secondly by Nature Precedings, of a research poll by Pielke Sr, James Annan and Fergus Brown surveying whether there is agreement among climate scientists on the IPCC fourth assessment report.
Pielke Sr. writes:
“It is clear that the AGU EOS and Nature Precedings Editors are using their positions to suppress evidence that there is more diversity of views on climate, and the human role in altering climate, than is represented in the narrowly focused 2007 IPCC report”.
There’s a further post and comment stream over on Brown’s blog.
I’m not privy to the inside information on why their paper was rejected from both EOS and Nature Precedings, but it seems to me that there are (at least) two point to be made here:
Firstly, as William Connolley points out in the comment thread on Brown’s blog, the conclusion of the poll that “there is not a universal agreement among climate scientists about climate science as represented in the IPCC’s WG1” is a strawman.
This is precisely one of the bugbears that Romm has with the term ‘consensus’: is it ‘unanimity’ or ‘the judgment arrived at by most of those concerned’?
“Many, if not most, people hear the second meaning: ‘consensus’ as majority opinion”, argues Romm – meaning that even if every living scientist doesn’t agree, there can still be a consensus.
As for sample design, the authors themselves admit that the sampling does not follow standard protocol for opinion polls and further “cannot be tested for statistical significance” as “there is no currently available information on the complete community of ‘climate scientists’”.
This whole discussion is reminiscent of that on the survey by Hans Von Storch and Dennis Bray last year, discussed here on Climate Feedback, which similarly attempted to survey climate scientists’ responses to bold statements on climate change, and had potentially biased sampling.
Whether or not opinion on climate change is relevant, it seems the debate is still open on how it can be gauged in a way that is scientifically credible.
Olive Heffernan