Tomorrow’s March for Science will draw many thousands in support of evidence-based policy making and against the politicization of science. A concrete step toward those worthy goals would be to convene a “Red Team/Blue Team” process for climate science, one of the most important and contentious issues of our age.

The national-security community pioneered the “Red Team” methodology to test assumptions and analyses, identify risks, and reduce—or at least understand—uncertainties. The process is now considered a best practice...