Summary: Many factors have frozen the public policy debate, but none more important than the disinterest of both sides in tests that might provide better evidence — and perhaps restart the discussion. Even worse, too little thought has been given to the criteria for validating climate science theories (aka their paradigm) and the models build upon them. This series looks at the answers to these questions given us by generations of philosophers and scientists, which we have ignored. This post shows how Popper’s insights can help us. The clock is running for actions that might break the deadlock. Eventually the weather will give us the answers, perhaps at ruinous cost.
“Confirmations should count only if they are the result of risky predictions; that is to say, if, unenlightened by the theory in question, we should have expected an event which was incompatible with the theory — an event which would have refuted the theory.”
— Karl Popper in Conjectures and Refutations: The Growth of Scientific Knowledge (1963).
“I’m considering putting “Popper” on my list of proscribed words.”
— Steve McIntyre’s reaction at Climate Audit to mention that Popper’s work about falsification is the hallmark of science, an example of why the policy debate has gridlocked.
This graph creates a high bar for useful predictions by climate models
What test of climate models suffices for public policy action?
Climate scientists publish little about about the nature of climate science theories. What exactly is a theory or a paradigm? Must theories be falsifiable, and if so, what does that mean? Scientists have their own protocols for such matters, and so usually leave these questions to philosophers and historians or symposiums over drinks. Yet in times of crisis — when the normal process of science fails to meet our needs — the answers to these questions provide tools that can help.
A related but distinct debate concerns the public policy response to climate change, which uses the findings produced by climate scientists and other experts. Here insights about the dynamics of the scientific process and the basis for proof can guide decision-making by putting evidence and expert opinion in a larger context.
A previous post in this series (links below) described how Thomas Kuhn’s theories explain the current state of climate science. This post looks to the work of Karl Popper (1902-1994) for advice about breaking the gridlocked public policy debate about climate change. At the end of this post is the best-known section of his work about this.
Popper said scientific theories must be falsifiable, and that prediction was the gold standard for their validation. Less well known is his description of what makes a compelling prediction: it should be “risky” — of an outcome contrary to what we would otherwise expect. A radical new theory that predicts that the sun will rise tomorrow is falsifiable by darkness at noon — yet watching the dawn provides little evidence for it. Contrast that with the famous 1919 test of general relativity, whose prediction was contrary to that of the then-standard theory.
How does this apply to climate science?