Hot Air : . The Psychology of C 02 - Induced Climatic Change

Since 1957, the Mauna Loa Observatory has recorded a yearly increase of approximately one-third of I% in the CO, (carbon dioxide) concentration of the Earth's atmosphere (Bacastow & Keeling, 1977). Although CO, concentrations are minute (on the order of 330 ppm), they play a major role in regulating the Earth's climate, particularly its temperature. Current projections indicate a doubling of CO, levels by the year 2030 with a consequent average warming (at the surface) of 3-4'C Perhaps more important than the mean change is the differential warming at different latitudes, from 2'C at the equator to II 'C at the poles (Manabe & Wetherald, 1975). Reduction of the temperature gradient between different latitudes will likely mean a substantial reduction in atmospheric and oceanic circulation One can anticipate marked changes in fisheries and agriculture, with a melting of the polar ice caps a distinct possibility. Although point predictions are extremely unreliable at the moment, it seems to be a reasonable assumption that CO:rinduced variations in temperature and precipitation patterns will lead to "better weather" in some places and "worse weather" in others. If, for example, climatological patterns return to those characterizing the Altithermal Period 4000-8000 years ago, when the world was several degrees warmer than it is how, the habitability of the Canadian prairies and the Sahel would increase as the former became warmer and the latter wetter. On the other hand, reduced precipitation in the southern Great Plains of the United Stales would remove vast acreages from the stock of arable land (Kellogg, 1978) However, even areas with improved climate might be adversely impacted by such changes. The legacy of industrialization and colonialism has been the establishment of highly specialized and relatively inflexible land use and agricultural patterns An underdeveloped equatorial country might have neither