Knowledge about the magnitude of nitrous oxide (laughing gas emissions from road traffic is insufficient and unreliable. Because nitrous oxide is a potent "greenhouse gas", emissions of this gas can be compared to emissions of carbon dioxide. It is estimated that between four and six per cent of the total greenhouse effect of carbon dioxide and nitrous oxide in motor vehicle exhaust emissions will be attributable to nitrous oxide in 1995 and 2000. It therefore seems as though nitrous oxide makes a small but not insignificant contribution to the greenhouse effect of motor vehicle exhaust emissions. At the same time, the use of catalytic converters helps to reduce emissions of other gases with a greenhouse effect. It is still too early to say whether the catalytic converter has a negative or positive effect on emissions of greenhouse gases. (A)
Abstract