Economic responses to global warming: Prospects for cooperative approaches

At the outset, any cooperative approach to global warming will have to reach some rough consensus on two sets of magnitudes and the marginal trade-off between them. One set of magnitudes relates to CO2 production and abatement. It is the cost and difficulties of reducing energy use by households, farms, and industry, and of switching to cleaner fossil fuels or converting to nonfossil energies. These are the kinds of things that economists and engineers, sometimes sociologists and architects, have been working on with special motivation since 1973. The uncertainties remain great, and they increase many-fold when projected to the middle of the next century. But these estimates do receive attention. The other set of magnitudes has to do with the impact of changing climate on economic productivity, on health and comfort, on the quality of life in general, and on the differential rates of progress among countries. These estimates, on which virtually no work was done until recently, are doubly uncertain. In this study the author offers a judgment about the magnitude of the consequences of failing to reduce CO2 emissions drastically below what they would be in the absence of such an effort. The author takes 'drastic' to mean anything between an emissions growth rate half of what it would otherwise be and an emissions growth rate of zero beginning one or two decades from now - that is, annual emissions leveling off within a decade or two. That level would still leave emissions growing at the maximum achieved rate