The Flaw of Averages: Why We Underestimate Risk in the Face of Uncertainty

CHAPTER 37

The Flaw of Averages and Climate Change

Everyone is talking about it, everyone is uncertain about it, and everyone is asking questions: How much hotter will it get? How high will the oceans rise? What should we do about it? Give us the numbers.

Why the Earth’s Average Temperature Is Falling

As I began my own investigation of climate change, I realized that current researchers had ignored some important aspects of the problem, which, if taken into account, indicate that average temperature is likely to decrease not increase.

Given the growing number of upstart nuclear-armed states, the chance of thermonuclear war is on the rise. And according to experts, the dust kicked up by a robust exchange of such weapons would significantly block the planet’s solar heating, “causing surface temperatures to drop drastically.”¹ Major asteroid strikes and catastrophic volcanic events would have similar effects. Taking these disasters into account drags the average temperature way down. Of course, like people with their heads in the oven and their feet in the freezer, humanity may not be comfortable in any event.

But seriously, folks, the Flaw of Averages permeates our discussion of climate change in other ways as well. Before addressing this issue I will attempt to frame the problem.

1. The earth’s temperature has varied over time. Figure 37.1 shows the relative temperature over the past 420,000 years, as determined from an ice sample taken at the South Pole. The Vostok Ice Core ...