Climate activism has a long history of innumeracy and gaps in baseline scientific knowledge (ask an activist how much warming is projected from now to 2100 in a moderate IPCC scenario – the flagship warming phenomenon). Some years ago, I came upon something so stupid that it paralyzed me. It locked my brain when I tried to write about it, and I let it sit for years like a Horcrux I dare not touch. Just knowing that it was out there bothered me.

It’s the opening paragraph of a 2012 Rolling Stone article by Bill McKibben – “Global Warming’s Terrifying New Math”. It’s a remarkable artifact that I’ve come to use as a test of applied intelligence and reading ability. Only one person has ever passed, and every climate scientist I’ve tried has failed, including Gavin Schmidt and Katharine Hayhoe:

If the pictures of those towering wildfires in Colorado haven’t convinced you, or the size of your AC bill this summer, here are some hard numbers about climate change: June broke or tied 3,215 high-temperature records across the United States. That followed the warmest May on record for the Northern Hemisphere – the 327th consecutive month in which the temperature of the entire globe exceeded the 20th-century average, the odds of which occurring by simple chance were 3.7 x 10-99, a number considerably larger than the number of stars in the universe.

The final, bolded clause is the test. Focus on his claim – the 327th consecutive month that the temperature of the globe exceeded the 20th-century average, on which he performs some sort of probability calculation. (From now on, I’ll abbreviate the 20th-century average as the 20C average, not to be confused with the actual value, which was 13.9 °C.)

Pause here and ponder his sentence. Do you understand what he’s saying? What does he mean by his “odds” claim? Is his statement valid? Is it true? What do you need to know to evaluate it?