Temperature difference from normal in 2016. (NASA)


In a recent op-ed, Steven Koonin, a professor at New York University, called for the establishment of a “Red Team/Blue Team” process for climate science. Environmental Protection Agency Administrator Scott Pruitt made a similar request in an interview with Breitbart News, and demanded “a true, legitimate, peer-reviewed, objective, transparent discussion about CO2.”

Such calls for special teams of investigators are not about honest scientific debate. They are dangerous attempts to elevate the status of minority opinions, and to undercut the legitimacy, objectivity and transparency of existing climate science.

The basic premise of these “Red Team/Blue Team” requests is that climate science is broken and needs to be fixed. The implicit message in the requests is that scientists belong to tribes, and key findings of climate science — such as the existence of a large human-caused warming signal — have not undergone adequate review by all tribes. This tribalism could be addressed, Koonin believes, by emulating Red Team/Blue Team assessment strategies in “intelligence assessments, spacecraft design, and major industrial operations.”

In Koonin’s view, “traditional” peer-review processes are flawed and lack transparency, and international scientific assessments do not accurately represent “the vibrant and developing science.” He implicitly accuses the climate science community of “advisory malpractice” by ignoring major sources of uncertainty. To use present-day vernacular, both Koonin and Pruitt are essentially claiming that peer-review systems are rigged, and that climate scientists are not providing sound scientific information to policymakers.

We do not consider ourselves to be members of any team or tribe. Our goal is not to “win” against “the other side.” Our prime motivation is to understand the natural world, and to use that knowledge and understanding to inform sensible decisions on important public policy questions. Whether we succeed in doing so is what we are ultimately judged on.

The peer-review system criticized by Koonin and Pruitt is imperfect, but it is the best system we have, and has served science well for several centuries.

The international assessments Koonin has questioned are made by large groups of experts, and are reviewed in an extraordinarily open and transparent way. These assessments receive detailed comments from many hundreds of scientists uninvolved in the writing of the assessment, with expertise in a wide range of fields, as well as from industry stakeholders and government representatives. All comments received are logged and made publicly available, together with responses from the assessment authors. Independent review editors determine whether the authors’ responses are accurate and adequate. Developing science, far from being ignored, is confronted directly and openly in such assessments.

Koonin’s claim that important uncertainties are neglected is patently incorrect. Scientists have spent many decades kicking the tires of climate science, identifying and quantifying key uncertainties, and trying to reduce those uncertainties. Critical examination of models, data and theory is not a fringe activity.

All scientists are inveterate tire kickers and testers of conventional wisdom. To paraphrase the Geico commercial, “If you’re a scientist, that’s what you do.” The highest kudos go to those who overturn accepted understanding, and replace it with something that better fits available data. Even after all the tire kicking, there is strong scientific consensus that planetary-scale warming is now unambiguous, and that human activities are the dominant contribution to this warming.

Critiques of this consensus have been offered up for decades. Each critique is often presented as a kind of smoking gun — one piece of evidence that falsifies all other evidence and understanding. There are many examples of such putative smoking guns. The ballistics of each gun has been carefully tested by thousands of scientists around the world. The “natural causes” gun doesn’t fit the overwhelming evidence of human-caused climate change. The “no warming” gun is inconsistent with reality.

If you’re a climate scientist, you’ve likely spent years of your career going down such rabbit holes, evaluating “natural causes” and “no warming” claims. You’ve considered and debated these claims. You’ve put them through their paces. They do not hold up to available evidence. Only the most robust findings survive peer review and form the basis of today’s scientific consensus.

Science has substantially improved our understanding of the physical climate system, the reality of human-caused warming, and the likely climatic outcomes if we do nothing to reduce emissions of greenhouse gases. Rejecting this tried and tested understanding would constitute real “advisory malpractice,” and would delay effective action to address human-caused climate change.

In short, climate science is not broken. It does not need fixing. We hear similar “broken” arguments about the media, the courts and our democracy itself. We are told that only one team or person can fix the problem; that if we place our trust in that one team, that one person, everything will be fine. In the case of climate science, we choose to place our trust in peer review and in the scientific community — not in teams appointed by Koonin or Pruitt.

Benjamin Santer is an atmospheric scientist and member of the U.S. National Academy of Sciences.

Kerry Emanuel is a professor of atmospheric science at the Massachusetts Institute of Technology.

Naomi Oreskes is a professor of the history of science at Harvard University.