Carbon Dioxide and Climatic Change

Abstract

Certainties and uncertainties in the issue of the greenhouse gases are discussed. It is an established fact that the concentrations of these trace gases — CO₂ chlorofluorocarbons (CFC), methane, nitrous oxide and ozone — are increasing in the lower atmosphere as a result of human activities. The contribution of coal use to the greenhouse effect is about 15 to 20%. Future emissions of the greenhouse gases form one of the greatest sources of uncertainty. The potential for reducing emissions of the greenhouse gases is discussed. While steps are being taken to control CFC, the greenhouse gases with the greatest rate of increase, the scope for reducing CO₂ emissions is limited. Climatic model results suggest that there will be a noticeable global warming in one or two decades with more uncertain regional changes. Observations are consistent with these results but there is as yet no conclusive causal link with increases in the greenhouse gases.