Statistical Evaluation of Trends in Ambient Concentrations of Nitric Oxide in Los Angeles

Abstract

The aerometric data on nitric oxide at several air monitoring sites in Los Angeles County for the period of 1959-1974 are statistically analyzed to determine trends in the concentration levels. Time series and intervention techniques are used to filter out the effects of seasonality, serial correlations, and short-term trends in weather variables. The ambient impacts of the 1966 and 1971 automobile exhaust programs are evaluated in terms of the trend parameters. © 1978, American Chemical Society. All rights reserved.