Nowadays, television news shows and newspaper and magazine articles that mention global warming rarely resort to outright lies
like this grotesque piece of propaganda
. Instead, you'll likely catch a reportorial "balancing" act that purports to show "both sides." Scientists, you'll be told, don't all agree that humans are causing the earth's climate to change, the implication being that an intellectual wrestling match is going on among experts in the know.
In fact, not all scientists do agree that humans are causing global warming. As researchers under the guidance of John Cook at Skeptical Science discovered in a "citizen science" survey of 11,944 peer-reviewed articles, 1.6 percent of the authors expressing an opinion on the subject rejected or were uncertain about the consensus that the earth is undergoing anthropogenic (human-generated) global warming (AGW). And 97.1 percent of the nearly 4,000 articles in which the author(s) took a position endorsed the AGW consensus. (The survey was published May 15 in Environmental Research Letters as an open access article.)
The survey will not, of course, persuade the professional deniers, several of whom have already weighed in with attacks on the credibility of Cook and Skeptical Science itself. What optimists might hope for, however, is that the media will finally get the message and stop implying that some significant proportion of scientists dispute the anthropogenic nature of global warming. If only we could get the number of warming rejectionists in Congress down to 1.6 percent.
Cook's team of volunteers, recruited from the Skeptical Science website's readers in eight countries, expanded on an original survey conducted in 2004 by Naomi Oreskes. That survey found 928 peer-reviewed articles in the scientific literature from 1993-2004. Here's how the Skeptical Science team did its work:
We performed a keyword search of peer-reviewed scientific journal publications (in the ISI Web of Science) for the terms 'global warming' and "global climate change" between the years 1991 and 2011, which returned over 12,000 papers. John Cook created a web-based system that would randomly display a paper's abstract (summary). We agreed upon definitions of possible categories: explicit or implicit endorsement of human-caused global warming, no position, and implicit or explicit rejection (or minimization of the human influence). [...]
We took a conservative approach in our ratings. For example, a study which takes it for granted that global warming will continue for the foreseeable future could easily be put into the implicit endorsement category; there is no reason to expect global warming to continue indefinitely unless humans are causing it. However, unless an abstract included (either implicit or explicit) language about the cause of the warming, we categorized it as "no position."
The reviewers also asked the authors of some 2,100 articles to rate their own views about AGW. In this short video, Cook explains some of the details:
Please continue reading below the fold for more on the survey.
Comments are closed on this story.