Planetary Warming: Realities and Responses

Abstract

THE POSSIBILITY OF PRONOUNCED AND EXTRAORDINARILY RAPID planetary warming induced by anthropogenic releases of carbon dioxide and other greenhouse gases has captured broad public attention because of its catastrophic frissons. In the Western context the simplest outline of the causal sequence has Biblical reverberations: the sin of ever-expanding industrialization and combustion of fossil fuels leading to higher atmospheric concentrations of greenhouse gases may bring planetary warming sufficient to melt the polar ice sheets; and the punishment of a new deluge will obliterate much of the civilization's handiwork.' The primordial scale and catastrophic nature of the eventual disaster readily capture the popular imagination, while the complexity of the processes leading to planetary warming stimulates intensifying, high-profile scientific inquiries across many disciplines. In the United States, the first development is confirmed by the appearance of stories on the covers of masscirculation weeklies and monthlies and on television specials, by a sensationalizing series of Congressional hearings, and by the adoption of planetary warming as a prominent topic for international politics.2 The second development is attested to internationally by a growing number of multi-authored volumes gathering the explosively expanding scientific output now amounting to thousands of published items.3 Regardless of the actual rate of future warming and its identifiable ecosystem and socioeconomic consequences, apprehension about man-induced climatic change will be with us for generations to come. Sensible appreciation of basic realities and possible implications of planetary warming driven by accumulation of greenhouse gases should thus be a part of any well-founded appraisal of civilization's prospects for the next century. Such an understanding requires, first of all, the separation of relatively skimpy facts from abundant conjectures, then an outline of both risks and benefits of planetary warming, and finally a review of possible policy options and a critical evaluation of their adoption chances and desirabilities.