"The crucial step in this is you're taking out all preconceived notions, political biases, people's emotions about this," he added.

To set up the study, the researchers first recruited an expert set of economists and statisticians to serve as test participants. None of these participants knew the study had anything to do with climate change.

The researchers also compiled a list of contrarian statements commonly used by climate doubters to question the existence or extent of anthropogenic climate change — for instance, the idea that Arctic sea ice is growing, not shrinking. To make sure these statements were representative of ideas commonly included in contrarian discourse, the researchers conducted a search of prominent climate skeptic blogs, verifying that each chosen statement was a popular hit.

During the test, the researchers featured such a statement, along with the corresponding climate data — but they changed the labels and wording, making it appear that they were displaying information about entirely unrelated topics, such as agricultural output or business profits. They then asked the expert participants to answer a series of questions about whether they thought the given statement confirmed or contradicted the accompanying data; whether the statement seemed misleading; and whether the statement was appropriate for use by policy-makers or industries.

Just to shake things up a little, the researchers also administered the test to some participants using statements supporting the ideas of mainstream climate science (also disguised, of course). The difference between the responses in each case was striking.

"Across two groups of experts and across six different scenarios, contrarian claims were judged to be misleading, inaccurate, and unsuitable for policy advice," the researchers wrote in the paper. "Conversely, mainstream scientific interpretations were found to be accurate and suitable for policy advice overall."

"It's a huge effect," Lewandowsky added. "They are about as far apart as anything I've seen."

As an added test, the researchers asked the participants to predict what the masked data should look like in the future — and in general, the experts made predictions in line with what's been projected by mainstream climate scientists.

"So no one thought the Arctic was going to recover — they thought it was going to continue melting, because that is what the data show," Lewandowsky said.

But not everyone is convinced. According to Jonathan Jones, a physics professor at the University of Oxford who has critiqued previous research published by Lewandowsky, a problem with the study is the data it chooses to begin with.

"The obvious problem is that because they have control over both the choice of data set used to assess a contrarian claim and over the corresponding 'consensus claim,' it is essentially trivial to construct situations where the data supports the consensus claim and opposes the contrarian claim," he added. "In reality, many of the real arguments are over precisely which data set to use (there are several competing data sets for global temperatures) and over which time periods to use (recent trends or longer term trends)."

Most climate scientists feel that using longer-term trends to make inferences and projections about the Earth's changing climate — say, for temperature increase or Arctic ice loss — is best practice, and that short-term trends are not always indicative of ongoing global patterns in factors like temperature or precipitation.

Those remaining skeptical of the science of climate change will surely object to the experimental design. But the researchers say the findings strip away preconceptions to prove a basic point: that across disciplines, experts know good science when they see it.

Washington Post