When dealing with global warming, the size of the risk matters

Abstract

Climate change is both high-impact and high-probability. Probabilities matter. Take strangelets as one extreme. They are particles with the potential to trigger a chain reaction that would reduce the Earth to a dense ball of strange matter before it explodes, all in fractions of a second. That’s a high-impact event if there ever was one. It’s also low-probability. Really low probability. At the upper bound, scientists put the chance of this occurring at somewhere between 0.002% and 0.0000000002% per year, and that’s a generous upper bound