PolitiFudging climate change consensus

PolitiFact jumped on Republican congressional hopeful Lenar Whitney's recent claim that global warming is a hoax.

We're not going to delve into whether Whitney's claim was true or false, or even whether her YouTube video promoting her beliefs was a wise election strategy.  We're simply concerned in this case with the methods PolitiFact uses to support the claim of a scientific consensus backing climate change (a.k.a. global warming).

First:

Among climate researchers most actively publishing scientific articles, at least 97 percent believe in anthropogenic climate change, found one 2009 study published in the Proceedings of the National Academy of Sciences, a scientific journal. The study examined published scientific articles and surveyed experts.

At Zebra Fact Check, I reviewed each of the evidences used to support the claim of a scientific consensus on climate change.

The study PolitiFact describes above was led by William R. L. Anderegg.  PolitiFact's description of this study is reasonably accurate, but glosses over the following concerns.  Anderegg and company deliberately narrowed the survey group down to the researchers publishing most actively.  That method allows intimidation of the editors of scientific journals to artificially establish the expertise of the survey group.  Part of the scandal discovered through the release of the East Anglia email concerned the efforts of scientists to keep journals from publishing articles by climate change skeptics.

It's manifestly obvious the study's methodology was designed to give added weight to the views of scientists who had published the most.  And that's not a good method for measuring scientific consensus in the field of study.

Second:

Another survey out of the University of Illinois found that 82 percent of earth scientists (out of more than 3,000 respondents) believe that global temperature shifts are human-caused. Among climate-specific earth scientists who responded, 97.4 percent said they believe in human-caused climate change.

In this case, PolitiFact and Lauren Carroll are simply guilty of bad reporting.  The survey PolitiFact used as its evidence, by graduate student Maggie Kendall Zimmerman and professor Peter T. Doran, concerned the answers to 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?

In other words, 82 percent of earth scientists surveyed believe human activity is a significant contributing factor.  PolitiFact helpfully translates that into "human-caused."

Among earth scientists studying climate, 97.4 percent believe human activity is a significant contributing factor.  PolitiFact likewise translated that into believing climate change is "human-caused."

Thanks to the muddled definitions supported by the media, it's likely that most climate change skeptics believe humans are a significant cause of climate change. A skeptic may not believe humans cause most or all of climate change yet at the same time think humans contribute significantly to climate change.

It's heartwarming, if not exactly a cause of global warming, to see PolitiFact routinely engaging in behavior that, if performed by a Republican, would warrant something like a "Half True" rating (or worse) on the "Truth-O-Meter."


Clarification Aug. 9, 2014:
Added the word "following" in the midst of the first sentence of the fifth paragraph to clarify intent.

More on PolitiFact's deceptive Rubio/climate correction

We've uncovered a bit more evidence of PolitiFact's dishonest correction of its climate-change hit piece on Sen. Marco Rubio (R-Fla.).

For review, here's the correction notice PolitiFact attached to its amended article:

CORRECTION: This story was updated on May 15 to clarify that 97.1 percent of the studies that took a position on global warming agreed that there's been a negative human impact on the atmosphere; more than half the studies did not take a position. Also, the story clarifies that the 2013 report looked at studies, not individual scientists.

The original article wasn't unclear about the 2013 report. It flatly said the report indicated 97.1 percent of scientists disagree with Rubio's supposed claim (PolitiFact blew and continues to blow the reporting on what Rubio said) that humans do not contribute to climate change.

Here's how PolitiFact was publicizing the Rubio fact check on its list of stories (red oval added to draw attention to the false reporting):

PolitiFact's clarification is not a clarification.  It's a gloss on a reporting error.

Here's how the Rubio blurb appears today:

PolitiFact's original article encouraged readers to conclude that 97 percent of scientists agree the Antarctic ice shelf is collapsing because of human-caused climate change.  That's a deception far worse than the Jeep ad from the Romney campaign that PolitiFact awarded its 2012 "Lie of the Year."  And the current version remains more misleading than that Romney ad.

PolitiFact continues climate change smear of Rubio

I noted over at Zebra Fact Check last year how PolitiFact has enlisted itself to aid in tarring various Republican politicians as "climate change deniers."  PolitiFact continued that effort this month:

Scientists have been issuing more new reports on the irreversible effects of climate change in recent weeks. Two groups reported on May 12, 2014, that the global sea level will rise at least 10 feet, accelerating to a dangerous pace after the next century.

Just a day before those reports were released, Sen. Marco Rubio, R-Fla., sat down with ABC’s Jonathan Karl on This Week. Talk turned to climate change, where the possible Republican presidential candidate denied a link between humans and the changing environment.

PolitiFact wasn't alone in its interpretation of Rubio's remark.  Unfortunately, PolitiFact didn't included enough context to make clear what Rubio was talking about.  Lucy McAlmont, writing at Patterico's Pontifications, took note of the cyclone of media spin and provided that context (bold emphasis carried over from McAlmont's transcript):

KARL: Miami, Tampa, are two of the cities that are most threatened by climate change. So putting aside your disagreement with what to do about it, do you agree with the science on this? I mean, how big a threat is climate change?

RUBIO: I don’t agree with the notion that some are putting out there, including scientists, that somehow, there are actions that we can take today that would actually have an impact on what’s happening in our climate. Our climate is always changing. And what they have chosen to do is take a handful of decades of research and say that this is now evidence of a longer term trend that’s directly and almost solely attributable to manmade activity. I do not agree with that.

KARL: You don’t buy that.

RUBIO: I don’t know of any era in history where climate has been stable. Climate is always evolving and natural disasters have always existed.

KARL: Let me get this straight. You do not think that human activity, the production of CO2 has caused warming to our planet?

RUBIO: I do not believe that human activity is causing these dramatic changes to our climate the way these scientists are portraying it. That’s what I do not — And I do not believe that the laws we pass will do anything about it. Except it will destroy our economy.

Reading Rubio's responses to Karl, it should be obvious that PolitiFact reports falsely when it says Rubio denied a link between humans and the changing environment. Rubio acknowledges people contribute to climate change but questions some of the more extreme claims.
 

PolitiFact provided a great example of an extreme claim.  We assume PolitiFact did this unknowingly.

The Ice Sheet

PolitiFact led the Rubio fact check with this:

Scientists have been issuing more new reports on the irreversible effects of climate change in recent weeks. Two groups reported on May 12, 2014, that the global sea level will rise at least 10 feet, accelerating to a dangerous pace after the next century.

That rise in sea level is a result of the irreversible effects of climate change?  And relevant to Rubio's skepticism regarding the size of mankind's role in climate change?

The hotlink embedded in PolitiFact's story leads to an article in The New York Times, where we find this:

Scientists said the ice sheet was not melting because of warmer air temperatures, but rather because relatively warm water that occurs naturally in the depths of the ocean was being pulled to the surface by an intensification, over the past several decades, of the powerful winds that encircle Antarctica.

The Times' story goes on to note that (unnamed) researchers think global warming may have contributed to the wind pattern affecting the ice sheets.

For PolitiFact, somehow the tenuous scientific link between global warming and the collapsing ice sheet makes a perfect intro to its Rubio fact check.

That's irony.

A 97.1 Percent Consensus and a PolitiFact Correction

The original version of the Rubio fact check claimed 97.1 percent of scientist disagreed with Rubio.  We looked forward to dissecting that blunder.  Now we find PolitiFact buried it with the following correction:

CORRECTION: This story was updated on May 15 to clarify that 97.1 percent of the studies that took a position on global warming agreed that there's been a negative human impact on the atmosphere; more than half the studies did not take a position. Also, the story clarifies that the 2013 report looked at studies, not individual scientists.

That's how to do a dishonest correction.  PolitiFact buried its inaccurate reporting by clarifying that the 97.1 figure was a select group of science papers, not scientists.  And simply eliminates the inaccurate reporting, pretending it never happened.

See Also

James Taylor of Media Trackers Florida also brought some attention to PolitiFact's smear of Rubio. We've picked out a section that includes some of PolitiFact's pre-correction malfeasance:

PolitiFact Florida is flat-out wrong regarding its scientific assertions. PolitiFact Florida justified its “False” ruling by claiming, “A May 2013 report analyzing all scientific papers that address the causes of climate change showed 97.1 percent of scientists agree that there’s been a negative human impact on the atmosphere.”

Taylor's quotation makes clear the magnitude of some the false reporting PolitiFact covers up with its correction spin.

Also See

Zebra Fact Check has an article that helps sort out what various studies show about the consensus on climate change.

PolitiFact could have benefited by consulting it before publishing its Rubio smear.