Slate's round up of other magazines pointed me to this chart in the Economist: A ranking of the oil-producing nations of the world. Saudi Arabia, Iraq, Iran, Kuwait and the UAE top the list, with what looks like around 65% of the total between them. What "years left" means exactly is not clear to me at all, and if anyone else can dig out the precise meaning, please let me know. My best guess is that the meaning is if we continue to pump those reserves at rates each of them are currently being pumped, they should last the indicated number of years.
That would explain why, even though Saudi Arabia is sitting on a much bigger pool than Iraq, Iraq is listed as having a longer lasting pool--it's not being very efficiently pumped right now, given problems like a sabotaged pipeline. This only highlights why using current rates of pumping is a bit of a silly metric when projecting how long an oil reserve will last over the course of the century: there's every reason to think rates of pumping will change. But if we accept that bit of silliness, it does give us a useful way to grasp the fundamental finiteness of what in gallons is a very large amount of oil.
The source of all this data is the BP Statistical Review of World Energy, 2004, released about a month ago. The dominance of the Middle East in the oil game is pretty clear in their bar graph. I will revert to a physicist's habits of rounding off numbers and thinking in terms of significant figures and orders of magnitude. It would appear that we provably have about 1200 billion barrels of usable oil in the earth--or, using more handy notation, 1.2 *(10 ^ 12) (pdf). We consume about 80,000 thousand barrels a day, or 8*(10^7) (pdf). That works out to about 3*(10^10). It doesn't take a genius to figure out that there aren't a whole lot of orders of magnitude difference between our yearly consumption and the provable usable total. A factor of fifty, a factor of one hundred. Fifty years, one hundred years, maybe two hundred years. This bit from the BP report on terminology seems to cloud the issue:
Ultimately recoverable resource (URR) is an estimate of the total amount of oil that will ever be recovered and produced. It is a subjective estimate in the face of only partial information. Whilst some consider URR to be fixed by geology and the laws of physics, in practice estimates of URR continue to be increased as knowledge grows, technology advances and economics change. Economists often deny the validity of the concept of ultimately recoverable reserves as they consider that the recoverability of resources depends upon changing and unpredictable economics and evolving technologies [Italics mine]
I don't know when economists became post-modernists, but all the economic and technological upheaval in the world does not invalidate the concept of URR. There IS a finite amount of oil in the earth, because, if nothing else, the earth itself is finite. A real and true value of the URR does exist. Our estimate of that value may be incorrect, in fact it almost certainly is. That is why it is called an estimate, and like all estimates, is most useful as a concept and less useful for very precise calculations. It is not a concept that can be ignored, however, or swept under the optimistic rug of "evolving technologies." Even accounting for the most fantastic discoveries, unforseeable drops in population grown, and a sudden reverse in global warming, we simply do not have the resources to sustain our current way of living for very long.
I don't know about you folks, but I intend to be alive in fifty or a hundred years, and I certainly intend for my descendants to be alive in two hundred. I don't have children yet, but I'm assuming when I do I will love them, and by extension care about the things they care about, including, say, their grandchildren. Talking about long term plans and the need for foresight and a sustainable energy plan is the most logical extension of true family values. Fifty or a hundred years. Maybe two hundred. Oil and energy will be the dominating issue of the twenty first century.
