What do those 97% agree on exactly?

The Organizing For Action staff seems to have a new campaign on the Obama website: Call out the Climate Change Deniers. They list a number of politicians that “deny the science of climate change” and the suggestion to call them out on it. How low can one go? They are obviously willing to do a lot of effort just to evade debate.

When visiting their campaign page, something caught my attention. It was the statement at the top of the page:

97% OF THE CLIMATE SCIENTISTS AGREE that climate change is real and man-made, and affecting communities in every part of the country.

There is that 97% consensus myth again. I remembered last time when they used a similar misrepresentation. Did they even look at those publications or even at the abstracts studying that illusive 97% consensus? I think they didn’t do this effort, not before and not now.

To my knowledge there were two surveys that involved climate scientists and that gave a “97% agreed” result: the Doran & Zimmerman (2009) survey and the Anderegg et al (2010) survey.

Doran & Zimmerman surveyed 10,257 earth scientists and asked whether they believed that the current global mean temperatures had risen, fallen or stayed the same since pre-1800 levels and whether they believed human activity was a significant contributing factor. They received 3,146 answers from which 79 scientists listed climate science as their area of expertise and also published more than 50% of their peer reviewed papers on the subject of climate change. 75 scientists from 77 answered the second question with “Yes”. Giving their 97.4% figure. By the way, they had to throw out more than 99% of the surveyed scientists to come to that result…

Anderegg et al compiled a database of 1,372 climate researchers and classified them either as “convinced by the evidence for anthropogenic climate change” or “unconvinced by the evidence”. They found 903 convinced, 472 unconvinced and 3 scientists were classified in both groups (that is about 34% unconvinced, so far for the consensus). That was obviously not exactly what they wanted, so they look further. They found that the unconvinced group consisted of only 2% of the top 50 climate researchers as ranked by expertise (number of climate publications), 3% of researchers of the top 100, and 2.5% of the top 200, excluding researchers present in both groups. The average of those three numbers gave their 97.5% figure.

My impression is that the 97% of both surveys depend heavily on the carefully made selections. But that is not the issue here.

The issue is that NONE of those two studies examined whether or not “climate change affect communities around the country”. None of the two studies even asked whether the human impact is large enough to be considered a problem.

“Climate Change is real and man-made” is really ambiguous. None of the two studies gave a definition of what they considered “Climate Change” or “significant” or what they exactly meant with “unconvinced”. This places the opinions of the surveyed scientists somewhere from “there is a human impact, but don’t worry” to “we change the climate and we have to do something, now”. I am not sure if the group that leans towards the first statement would agree that the Organizing For Action statement is correctly representing their opinion.

This is not the first time that Organizing For Action misrepresented the facts. Remember the “Obama” tweet (that actually came from Organizing For Action) with the claim that “Ninety-seven percent of scientists agree: climate change is real, man-made and dangerous” when talking about the Cook Survey? That tweet was actually more wrong than the above statement: Cook didn’t even count scientists (he and his group counted papers), he didn’t investigated whether climate change was dangerous at all and only 0.5% of the papers unequivocally were put in the 50% or more category.

So unless there is still another survey that showed a result of 97% scientists who agree and that also specifically asked if those scientist believed whether communities are affected by climate change, the Organizing For Action staff seem to have rather poor reading and/or comprehension skills.