Differences caused by stability class on dispersion in tracer experiments

• Published in: Atmospheric environment 1985, Vol.19 (7), p.1045-1051
• Main Authors: Atwater, Marshall A., Londergan, Richard J.
• Format: Article
• Language: English
• Subjects: Applied sciences; Atmospheric pollution; Exact sciences and technology; Pollutants physicochemistry study: properties, effects, reactions, transport and distribution; Pollution
• ISSN: 0004-6981; 1352-2310
• DOI: 10.1016/0004-6981(85)90188-X

A single source mass transfer technique by Hellums that provides a systematic method of fitting concentration data from a tracer dispersion experiment to determine horizontal and vertical dispersion coefficient values was used to determine revised dispersion estimates for tracer experiments. These revised coefficients were compared to results from standard analysis methods and to coefficients predicted by the Pasquill-Gifford curves. Differences in stability classification result in much larger differences in dispersion coefficients than the differences associated with the curve-fitting techniques. The stability class estimate inferred from the observed dispersion often differed by two or more classes from the estimate based on meteorology. The dT dz stability classification method was most correlated with the observed vertical dispersion, while the Turner and σ θ methods were most correlated with observed horizontal dispersion. Observed horizontal and vertical dispersion classes often differed from one another by two or more classes.