Going through some papers on my desk, I ran across this quote scribbled on a piece of paper:

Many droughts will occur; many seasons in a long series will be fruitless; and it may be doubted whether, on the whole, agriculture will prove remunerative.

That’s John Wesley Powell describing life in what he called the Arid Region, the lands west of the 100th meridian where rainfall averages less than 20 inches (~51 cm) per year. Less than that and it’s tough to make a go of it without irrigation, but Powell understood back then that you have to think about more than the annual average. What matters, he realized early on, is not only the mean but the variability around that mean.

It’s difficult to view Powell through the lens of history. We in the western U.S. tend to see our own ideas reflected in his. For me, it’s easy to imagine him now looking at the bungle we’ve made of things and saying, “I told you so.” But he did. His Report on the Lands of the Arid Region is amazing. Bernard DeVoto called it “One of the most remarkable books ever written by an American.”

(The Library of Congress has put the whole thing on line, and William deBuys included lengthy excerpts, along with a great introductory essay, in his collection of Powell’s writings.)