M. King Hubbert
I don’t usually go to the trouble of telling people where I get my scientific information. I prefer to have you suppose that it comes from my own research, grinding lenses and letting little balls roll down inclined planes and all that. This time, though, there’s a piece in a recent issue of Science that I want to tell you about and, if interested — and I think we all might be interested — go to the periodicals desk at the nearest halfway decent library, ask for the 13 March issue of Science and turn to page 142, where there is an article titled “How much coal remains?”
Of course, you could spend $15 to read it online, or if you are a member of the American Association for the Advancement of Science, you are already getting the magazine, so you can skip the drive to the library. (Am I a member? Nah! For the last thirty years I’ve been a Fellow, and thus entitled to put the letters F.A.A.A.S. after my name when I write crank letters to the New York Times, and don’t you forget it.)
Yes, the article’s about coal, but what it’s mostly about is the process called curve-fitting, and that’s what I am embarrassed to have to admit is a whole new world to me.
Go back to 1956 and a geophysicist named M. King Hubbert, who had an interest in bell curves. Those (as you of course know) are graphic models of some kind of process, let’s say something like railroad building.
In the beginning there’s hardly any of that going on, and so the dot you plot for that first year is barely above zero. By the second year it picks up a little, by the third year more than that. When you connect the dots, you have a line that rises shallowly at first, then ever more steeply, until you reach the time of peak production — I don’t know, say perhaps the 1890s in America, and the top begins to round off — and then to go down. And the curve you wind up with does look like a bell.
The insight of M. King Hubbert was to realize that when you’ve got as far as the peak of the period, you have a pretty good idea of what the final leg should look like. Or, to put it differently, you have a rough, but useful, description of what the terminal events will look like even though they haven’t happened yet.
So what did M. King Hubbert do with this insight? He issued a forecast saying that the peak period of American oil production would be in the 1970s (this was in 1956, remember?), and when did it happen? In 1970, causing a lot of peakists to begin to use Hubbert’s bell curve system.
They are doing it even now. China, for example, apparently using the bell curve system, has eliminated five-sixths of its claimed coal reserves. The coal is still there, it’s just not clear that it will ever be mined.
The American coal reserve has usually been given as 250 years. The best opinion now is at perhaps 100. The reserves of all of our fossil fuels are being sharply corrected. And it’s all due to Mr. Hubbert’s bell curves.
