What are the choices for our future sources of energy?
There are large reserves of solid oil—more than the remaining liquid fraction—in the form of oil shale or in gooey bitumen locked in the pores in sandstone, but the highly energy-intensive and expensive technologies aren’t in place to extract it. Reliance may shift initially to natural gas, but that resource is being depleted, too. Alternative energy scenarios could, in principle, ensure a smooth transition away from oil, but the pace of development of the alternatives must accelerate if they are to take up the slack when conventional oil production begins to decline globally in 10 years or so. Uncertainty comes into play not only in predicting the future, but also in trying to reconstruct the past. How is that situation different? Reconstructing the past is complicated by incomplete, sometimes inaccurate and sometimes conflicting information. Think of how difficult it has been for investigators to figure out what made the Space Shuttle disintegrate or TWA Flight 800 crash. Another com
