June 30, 2017

Can a Red Team Exercise Exorcise the Climate Debate?



E&E News is reporting (no paywall) that the Trump Administration is beginning a critical reviewor red team analysisof climate science. In recent weeks, EPA Administrator Scott Pruitt and Secretary of Energy Rick Perry had voiced support for the idea, echoing physicist Steve Koonin in the Wall Street Journal and climate scientists Judith Curry and John Christy.

Climate scientists and advocates have responded dismissively and Sen. Al Franken cornered Perry about the idea in a recent hearing. But this isn’t the right reaction. On the contrary, both climate scientists and advocates should see opportunity in a red team exercise. A properly-done red team exercise could both elevate the status of climate science in the Trump administration and among Republicans, and reset how we approach climate science as a nation.

Many climate skeptics suspect that the climate science community is caught up in political conformity that leans toward alarmism, and that alternative ideas about the causes and risks of climate change cannot break through peer review. Red teaming is designed to address such a situation. As Micah Zenko writes in his authoritative book Red Team: in institutions that are supposed to police themselves through internal processes, like the scientific community with peer-review, “even longtime analysts are susceptible to adopting the assumptions and biases of the institutions and subjects they are supposed to be objectively studying.” Whether climate science is caught in such a morass or not, many people in power think that it is. We have to find a way to unstick that belief if the climate debate is to move forward. A red team exercise is a fine way to do it.

In fact, red teaming outside the typical peer-review process has a long history in climate science; similar efforts have already been used to test the conclusions of climate science and the dangers associated with greenhouse gas emissions. In most of the previous instances, it has positively contributed to our understanding of climate science, and has generally elevated the status of climate science with decision makers.

The early IPCC studies could be considered a red team exercise. In the late 1980s, some scientists thought that human-caused climate change would emerge as a significant ecological and economic danger in the early 21st century. To evaluate that conclusion, and better understand the problem, the IPCC was created to review the whole body of evidence and present an acceptable consensus. It took that process more than 20 years to confidently reject non-human drivers as an explanation of recent warming.

In the 1990s, the team at the University of Alabama at Huntsville (UAH) was the first to use weather satellites to bootstrap a climate record. Their early records showed atmospheric cooling, a result that was surprisingly contrary to the warming trends observed in surface records. A second group of scientists suspected there were errors in the UAH analysis and embarked on an alternative (red team) analysis. Years later they proved that there were errors in the UAH analysis that caused it to underestimate warming and UAH correctly made adjustments. To this day, those two teams are working toward resolving the problems in measuring atmospheric temperature trends and iteratively producing new datasets. The newest resultsshowing that atmospheric warming trends are 140 percent higher than previously thoughtjust broke this week.

The Berkeley Earth Project started as a quasi-red team exercise that was designed to investigate how scientists combine measurements from weather stations around the planet into a global temperature record. That process involves a lot of technical data processing choices (with names like homogenization and kriging) that could potentially make temperature records biased or inaccurate. Skeptics thought that they would make the recorded temperatures too hot.

The project embarked on its own analysis, using raw weather station data and participating in an open scientific inquiry that resulted in peer-reviewed publications and a new reference-quality global temperature dataset. In the end, it found that the data processing that skeptics objected tothough it had problems that warranted investigationdid not significantly bias global temperature records. Through that process, Berkeley Earth founder Richard Muller publicly went from skeptic to believer.

No two red team efforts are the same, but in each of these, teams were assembled to test the assumptions and conclusions of others. Critically, each of these efforts was designed to make alternative analyses and original conclusions. They stayed close enough to the scientific community (recruiting in-group expertise to balance outside gadflies and participating in peer review) that their outcomes had a real effect on the directions of future climate research and the authority of the process both inside and outside climate science.

So as the administration designs its own red/blue review of climate science, they should keep those structural advantages in mind. If the review is simply a back and forth, as has been suggested by Steve Koonin, there is little chance that the process will have the buy-in of the science community and the administration, and it would risk looking like a kangaroo court to the public (or the 21st century version of the Scope’s Monkey Trial).  

The back and forth model has been tried before and has produced very little. In 2014, as part of its climate change statement review, the American Physical Society (APS), the scientific society for physicists in the United States, convened its own red/blue workshop. The workshop focused on a set of questions that challenged or sought to clarify statements from the 5th IPCC Assessment report of 2013. Those questions were addressed by six leading climate scientists: three scientists that reflected the body of mainstream opinion (Isaac Held, Ben Santer, and Bill Collins) and three scientists that objected to various findings from the IPCC and are frequently cited as climate skeptics (Richard Lindzen, John Christy, and Judith Curry).

The transcripts, however, demonstrated how difficult it is to pose a set of questions that is tractable and can be elucidated by tabletopor back and forthdebate. Most discussions broke down over misunderstandings, disparate definitions of terms and phenomena, and plain disagreement. All of those conflicts took place in front of a panel somewhat unqualified to judge their relative merit or novelty, because they were too far from their own expertise (physics) or the subjects were outside the expertise of the experts themselves (there was no expert in paleoclimate, for instance).  

While an interesting picture of the climate science debate, circa 2014, there is little that came of the APS review. I think that is largely a function of its form. The strongest red team exercises have buy-in from all parties and give the red team resources to perform original analysis along a set of critical questions. They also ensure that the team has the right mixture of expertise so that its results will be considered credible to the institution they are looking to influence (in this case, climate science). Lastly, they give the red team sufficient independence to come to original and creative conclusions.

Zenko’s book includes an interesting example. He recounts how the Intelligence Community (IC) performed multiple red team analyses regarding the suspected nuclear reactor in Syria in 2007. The IC was relatively certain that a mysterious facility in Eastern Syria was a nuclear reactor being built with technical assistance from North Korea. Before taking any action, however, the IC wanted to perform multiple red team analyses of their conclusions over several alternatives. One team was assigned the task of making the strongest case for the facility being anything other than a nuclear reactor. Combing through photographic and other evidence, that team eventually concluded that the most likely alternative conclusion was a decoy: a fake nuclear reactor.

How could such a process play out in climate? Both Administrator Pruitt and Secretary Perry have expressed doubt in the conclusion that greenhouse gas emissions are the primary cause of climate change (most scientists think that they are). So the administration might charge a team with making the case for the most likely alternative. My bet is that they find an “unspecified increase in greenhouse gas forcing.” If they do, then Pruitt and Perry should have sufficient cause to then ask a different red team the question: what should we do about it?