In Saturday’s WSJ, Matt Ridley completed his three part series on confirmation bias by looking at how it has impacted the debate over global warming:
It isn't just models, but the interpretation of real data, too. The rise and fall in both temperature and carbon dioxide, evident in Antarctic ice cores, was at first thought to be evidence of carbon dioxide driving climate change. Then it emerged that the temperature had begun rising centuries earlier than carbon dioxide. Rather than abandon the theory, scientists fell back on the notion that the data jibed with the possibility that rising carbon dioxide levels were reinforcing the warming trend in what's called a positive feedback loop. Maybe—but there's still no empirical evidence that this was a significant effect compared with a continuation of whatever first caused the warming.
The reporting of climate in the media is full of confirmation bias. Hot summers (in the U.S.) or wet ones (in the U.K.) are invoked as support for climate alarmism, whereas cold winters are dismissed as weather. Yale University's Dan Kahan and colleagues polled 1,500 Americans and found that, as they learned more about science, both believers and nonbelievers in dangerous climate change "become more skillful in seeking out and making sense of—or if necessary explaining away—empirical evidence relating to their groups' positions on climate change and other issues."
As one practicing scientist wrote anonymously to a blog in 2009: "honestly, if you know anything about my generation, we will do or say whatever it is we think we're supposed to do or say. There is no conspiracy, just a slightly cozy, unthinking myopia. Don't rock the boat."
Bring on the gadflies.
Ridley argues that the best way for scientists (and all of us for that matter) to avoid the perils of confirmation bias is to have their theories and the underlying data that support them challenged. This is the best way to ensure that they aren’t seeing what they want to see and ignoring evidence that contradicts their conclusions. It is through this process that the myriad scientific achievements that we celebrate and enjoy were made possible. If previous generations had just gone along with what the existing consensus on various scientific matters was at the time, we would not be where we are today. To function properly, science needs skeptics, it needs what Ridley calls the “gadflies” to challenge what might be the accepted wisdom of the day and ask if there might be alternative explanations that merit exploring.
Last night, we were watching a show on the Science Channel on the landing of the Curiosity rover on Mars. The motto of the Science Channel which is prominently displayed every time they go to a break is “Question everything.” And that seems like an appropriate credo for the subject that the channel covers.
But it doesn’t seem like one that’s embraced by many scientists and self-describing admirers of science when it comes to anthropogenic global warming. Those who skeptical about any part of the summary conclusion that the earth is warming, that said warming is man-made, and that the results will be catastrophic are shouted down, defamed, and told that the argument is over. That’s not science.
The reality is that the AGW supporters need the skeptics. They need to have their conclusions and data challenged. They need to make their arguments more convincing. They need to be sure that the evidence is indeed supporting their theories and not just seeing what they want to see to confirm them. They need to engage with those skeptics and to be willing to look beyond the “consensus” and honestly ask and answer questions about whether other explanations and outcomes are possible. Then, and only then, will the debate truly be on based on science.