Its aim was to give its viewers a tour through the shadowy world of sinister interests selling the idea that anthropogenic ("human-caused") global warming is a myth, a hoax, and a scam.
PBS reporter John Hockenberry put on screen crowds of Tea Party activists holding that view, and interviewed conservative activists like Tim Phillips (Americans for Prosperity) and Myron Ebell (Competitive Enterprise Institute).
These were described as "fighting science with doubt and delay."
Hockenberry interviewed - and heavily edited - only one skeptical climate scientist, Dr. Fred Singer. In response to Hockenberry's implication that the skeptics were few and unqualified, Singer replied that some 31,000 persons with scientific degrees had signed the 1998 "Oregon Petition," the key sentence of which is "There is no convincing scientific evidence that human release of carbon dioxide, methane, or other greenhouse gases is causing or will, in the foreseeable future, cause catastrophic heating of the Earth's atmosphere and disruption of the Earth's climate." There were, incidentally, 51 signers from Vermont, 22 of them with doctorates in science or medicine.
To dismiss the Oregon Petition, Frontline asserted at least twice during the program that "97 percent of active climate researchers" believe that humans are a significant cause of global warming. ("Significant" can range from "the most influential" to "barely detectable." ) Thus, why should you few skeptics be taken seriously?
The origin of this often-quoted percentage is curious. Canadian environmentalist Lawrence Solomon was a global warming believer until he authored a 2008 book entitled "The Deniers: The world-renowned scientists who stood up against global warming hysteria, political persecution, and fraud."
More recently he traced the origin of the "97 percent" assertion back to a two-minute online survey of 10,257 earth scientists, conducted in 2009 by two researchers at the University of Illinois.
The researchers, Doran and Zimmerman, deliberately excluded the solar scientists, space scientists, cosmologists, physicists, meteorologists and astronomers who might have thought that the sun and planetary movements might have something to do with Earth's climate.
They also decided that neither academic qualifications nor scientific accomplishment would be a factor in whose responses could be accepted - about 1,000 of those surveyed did not have a Ph.D., and some didn't even have a master's degree. They reduced the list to 3,146 who responded to these two questions:
1. When compared with pre-1800s levels, do you think that mean global temperatures have generally risen, fallen, or remained relatively constant?
2. Do you think human activity is a significant contributing factor in changing mean global temperatures? Ninety percent of the respondents answered "risen" to the first question, presumably assuming it referred to the pre-1850 Little Ice Age. Eighty two percent of the respondents answered "yes" to the second question.
Those percentages weren't impressive enough for the researchers, so they further reduced the sample until only 77 remained.
Seventy five of the select 77 said "yes" to both questions, producing the desired "consensus" finding that "97 percent of "active climate researchers" believe that humans are a significant cause of global warming. Those human activities, incidentally, include land use changes as well as greenhouse gas emissions.
This manufactured "consensus" is obviously dishonest, but Frontline repeated it twice while alleging that skeptical scientists were largely funded by fossil fuel interests and other undesirables.
One Vermont politician who has made himself a champion of a supposed climate change consensus is Gov. Peter Shumlin. He has repeatedly blamed human-caused "climate change" for every noticeable weather event, and predicts that unless checked it will lead to an "unspeakably horrid future."
"The evidence is overwhelming," he has declared, "and any other conclusion is simply irresponsible."
So you must accept Shumlin's personal conclusion about the Menace of Global Warming, or you're simply irresponsible, well beyond the pale of civilized discussion. This would be merely annoying, but for the fact that Shumlin's nonexistent climate change consensus is the indispensable rationale for his sweeping program of energy taxes, mandates, subsidies, regulations, and credits, many of which seem to produce wealth for his friends in the renewable industrial complex at the expense of everybody else.
John McClaughry is vice president of the Ethan Allen Institute (www.ethanallen.org).