Energy and climate: Today's, problem, not tomorrow's

Abstract

The steadily rising price of a tankful of gas reminds us that the days of cheap and abundant energy are coming to an end. Nevertheless, a number of recent studies conclude that we can continue to meet our energy needs through judicious use of the world's ample remaining stocks of fossil fuels, mainly coal, during a long transition to a sustainable global energy system. Damage to the earth's climate may be the major flaw in this strategy. Burning of fossil fuels returns to the atmosphere carbon that was extracted by ancient plants many millions of years ago, and thus increases today's airborne concentration of carbon dioxide. We have already produced an estimated 13 or so percent increase over pre-industrial levels. Although a minor constituent of the atmosphere, carbon dioxide plays a significant role in the earth's heat budget, and increases in its concentration are expected to lead to a warmer earth. A typical scenario critically studied by a panel of the U.S. National Research Council chaired by the late Jule Charney in the summer of 1979 supposes that continued growth in fossil fuel combustion would lead to a doubling in airborne concentrations by some time in the first half of the next century. The panel concluded that a global wanning of about 3 degrees Centigrade would result, with significant regional changes in precipitation, temperature, and other climatic characteristics. The panel members tried but were unable to find any factors that could reduce these expected changes to negligible proportions. An international study group in November 1980 concluded that future growth in energy consumption and carbon dioxide concentrations would be somewhat slower; however, their conclusions were qualitatively the same as those of the Charney group. Another National Research Council panel chaired by Thomas C. Schelling of Harvard University discussed the economic and social implications of these changes. They concluded that the issue would " . . . pose exceedingly difficult and divisive policy questions for all the world's na t ions . . . " In essence, they supported the conclusion of an earlier Academy study that climate change might be " . . . the primary limiting factor on energy production from fossil fuels over the next few centuries." Still, these studies of energy and climate might lull us into concluding that we can put off worrying seriously about man-made climate change for a half century or so. For both physical and political reasons, both conclusions may be terribly wrong. Physically, a doubling of carbon dioxide is no magic threshold. If we have good reason to believe that a 100 percent increase in carbon dioxide will produce significant impacts on climate, then