You Ought to Have a Look: Competing Theories for Source of Bias in Scientific Research

You Ought to Have a Look is a feature from the Center for the Study of Science posted by Patrick J. Michaels and Paul C. (“Chip”) Knappenberger.  While this section will feature all of the areas of interest that we are emphasizing, the prominence of the climate issue is driving a tremendous amount of web traffic.  Here we post a few of the best in recent days, along with our color commentary.

Two papers were announced this week that sought to examine the sources of bias in the scientific literature. They could not be more starkly opposed.

First off is a doozy of a new paper by Stephan Lewandowsky, Naomi Oreskes and colleagues that complains that skeptical viewpoints are disproportionately influencing the science of climate change. Recall that Lewandowsky and Oreskes are quixotic climate change denialslayers—conspiracy theorists of somewhat ill-repute.

According to a story in Science Daily (the Lewandowsky et al. paper was not available at the time of this writing) Lewandowsky and Oreskes argue that:

Climate change denial in public discourse may encourage climate scientists to over-emphasize scientific uncertainty and is also affecting how they themselves speak – and perhaps even think – about their own research.

Lewandowsky and Oreskes fret:

The idea that ‘global warming has stopped’ has been promoted in contrarian blogs and media articles for many years, and ultimately the idea of a ‘pause’ or ‘hiatus’ has become ensconced in the scientific literature, including in the latest assessment report of the Intergovernmental Panel on Climate Change (IPCC).

The Science Daily article continues:

Recent warming has been slower than the long term trend, but this fluctuation differs little from past fluctuations in warming rate, including past periods of more rapid than average warming. Crucially, on previous occasions when decadal warming was particularly rapid, the scientific community did not give short-term climate variability the attention it has now received, when decadal warming was slower. During earlier rapid warming there was no additional research effort directed at explaining ‘catastrophic’ warming. By contrast, the recent modest decrease in the rate of warming has elicited numerous articles and special issues of leading journals.

This asymmetry in response to fluctuations in the decadal warming trend likely reflects what the study’s authors call the ‘seepage’ of contrarian claims into scientific work.

And according the Lewandowsky, this is a problem because:

“It seems reasonable to conclude that the pressure of climate contrarians has contributed, at least to some degree, to scientists re-examining their own theory, data and models, even though all of them permit – indeed, expect – changes in the rate of warming over any arbitrarily chosen period.”

So why might scientists be affected by contrarian public discourse? The study argues that three recognised psychological mechanisms are at work: ‘stereotype threat’, ‘pluralistic ignorance’ and the ‘third-person effect’.

‘Stereotype threat’ refers to the emotional and behaviour responses when a person is reminded of an adverse stereotype against a group to which they belong. Thus, when scientists are stereotyped as ‘alarmists’, a predicted response would be for them to try to avoid seeming alarmist by downplaying the degree of threat. Several studies have indeed shown that scientists tend to avoid highlighting risks, lest they be seen as ‘alarmist’.

‘Pluralistic ignorance’ describes the phenomenon which arises when a minority opinion is given disproportionate prominence in public debate, resulting in the majority of people incorrectly assuming their opinion is marginalised. Thus, a public discourse that asserts that the IPCC has exaggerated the threat of climate change may cause scientists who disagree to think their views are in the minority, and they may therefore feel inhibited from speaking out in public.

Research shows that people generally believe that persuasive communications exert a stronger effect on others than on themselves: this is known as the ‘third-person effect’. However, in actual fact, people tend to be more affected by persuasive messages than they think. This suggests the scientific community may be susceptible to arguments against climate change even when they know them to be false.

We humbly assert that Lewandowsky, Oreskes, and colleagues have this completely backwards.

When global warming was occurring faster than climate models expected during the 1990s, there was little effort by the mainstream climate science community to look into why, despite plenty of skeptic voices (such as our own) pointing to the influence of natural variability.  Instead, headlines proclaimed “Global warming worse than expected,” which fueled the human-caused climate change hysteria (favored by the 1990s White House) and helped build the push for calls to regulate greenhouse gas emissions from fossil fuels.  But since the late 1990s, there has been no statistically significant warming trend in the highly-cited HadCRU4 temperature record, and both the RSS and UAH satellite records are now in their 21st consecutive year without a significant trend.  This behavior contrasted with, and called into question, the veracity of climate model projections. And it was these projections upon which rested the case for a dangerous human influence on the climate. Again, skeptic voices were raised in objection to the mainstream view of climate change and the need for government intervention. But this time, the skeptic voices were accompanied by data that clearly showed that rather than “worse than expected,” climate change was actually proceeding at a quite modest pace.

It was only then, with the threat of losing support for actions to mitigate climate change—actions that a top U.N. climate official, Christine Figueres, described as an effort “to intentionally transform the economic development model, for the first time in human history” —that the mainstream climate community started to pay attention and began investigating the “hiatus” or “pause”—the words so despised by Lewandowsky and Oreskes.

Through these research efforts, we have learned a lot about the role of natural variability in the broader climate system and how such variability impacts of projections of human-caused climate change (such as through a better understanding of the equilibrium climate sensitivity—how much warming results from a doubling of atmospheric carbon dioxide concentration).

In other words, science has been moved forward, propelled by folks who didn’t take the mainstream climate science at face value, and instead questioned it—i.e., Lewandowsky’s and Oreskes’ “deniers.”

The outcome of all of this is, in fact, the opposite of what Lewandowsky and Oreskes assert has occurred.  Rather than “skeptic” ideas “seeping” into science and leading to a false narrative, skeptic ideas instead have spurred new research and therefore new knowledge. Such was not the case when skeptics were being shut out. The only thing different now vs. 20 years ago, is that this time around, the existence of a profoundly inconvenient truth (a “hiatus” in global warming) gave public credence to the skeptics which forced them to be taken seriously by the scientific consensus-keepers. Incontrovertible evidence that threatened to tear down the meme of climate alarmism clearly required some sort of response.

Science is biased not by the inclusion of skeptical voices, but rather the exclusion of them.

In fact, this week, we announced the framework for an investigation into the existence of such bias.

We teamed with Dr. David Wojick to produce a Cato Working Paper titled “Is the Government Buying Science or Support? A Framework Analysis of Federal Funding-induced Biases” we describe:

The purpose of this report is to provide a framework for doing research on the problem of bias in science, especially bias induced by Federal funding of research. In recent years the issue of bias in science has come under increasing scrutiny, including within the scientific community. Much of this scrutiny is focused on the potential for bias induced by the commercial funding of research. However, relatively little attention has been given to the potential role of Federal funding in fostering bias. The research question is clear: does biased funding skew research in a preferred direction, one that supports an agency mission, policy or paradigm?

An interested reader may want to review the fifteen bias-inducing scientific practices that we identify and compare them with the “three recognised psychological mechanisms” that Lewandowsky and Oreskes assert are at work to see which seem to make the most sense.

Essentially, our project seeks to determine if the dog is wagging the tail. Lewandowsky and Oreskes propose the tail is wagging the dog.

Hopefully, in the not too distant future, we’ll be able to report back what we find in our investigations. We’ll be surprised if we find that exclusionary practices drive science forward more efficiently than inclusive ones!


Lewandowsky, S., N. Oreskes, J. S. Risbey, B. R. Newell and M. Smithson, 2015. Climate change denial and its effect on the scientific community. Global Environmental Change, (in press)