Concern over air pollutants has spread from their local and urban effects to the question of possible global atmospheric contamination. Analyses of the pollutants SOZ, NOL, CO, and hydrocarbons show that a part of these emissions derive from the natural environment and that there are, moreover, effective natural scavenging processes by which these pollutants are removed from the atmosphere. The result is that there is no evidence of significant increases in any of these pollutants on a global scale. In the case of COZ, where annual emissions of about 15 × 109 tons are only partly balanced by scavenging processes, there has been a steady increase in atmospheric COZ. concentrations. The world's combustion processes are based on oxidation; however, at present there is no evidence that the use of available fossil fuel reserves will cause any important change in global oxygen concentrations. by ELMER ROBINSON, Stanford Research Institute, Menlo Park, California 94025, United States of America
La préoccupation au sujet des effets locaux et urbains des contaminants de l'atmosphère a mené à la question de la possibilité de la contamination globale de l'atmosphère. L'analyse des contaminants S02, NO2, CO2 et les hydrocarbures montre qu'une partie de ces émissions provient de l'environnement naturel. De plus, il y a des procédés efficaces de balayage naturel pour éliminer ces contaminants de l'atmosphère. Donc il n'y a pas d'évidence à suggérer des augmentations significatives de ces contaminants à l'échelle globale. Les émissions annueiles de COz (15 × 109 tonnes) ne sont que partiellement balancées par les procédés de balayage; il y a ainsi une augmentation continue dans la concentration atmosphérique de COZ. Les procédés de combustion du monde se basent sur l'oxydation; mais à present il n'y a pas d'évidence à indiquer que l'emploi des réserves disponibles des combustibles fossiles peut changer significativement les concentrations d'oxygène globale
The prospective emission of ever-increasing amounts of air pollutants has brought the beginning of corrective action in the form of increasing controls on emissions to the atmosphere. However, the prospect of a steadily expanding world economy seems to lead necessarily to an increasing number of air pollution sources. Even if air pollution emissions from these sources are relatively well controlled, the probability still remains that there will be continued expansion of the total mass of pollutants emitted to the atmosphere. Thus, there is a need to know what is being emitted to the atmosphere, what happens to it, and what the prospect is that pollutants may accumulate in the atmospheric environment. Should there be a significant accumulation of pollutants in the atmosphere, then we must be concerned as to wh
