ABSTRACT OF THE THESIS

A Numerical Model for Traffic Volume and

Weekly Cycles of Total Suspended Particulates

by Nancy Carol Neuman, Ph. D.



Dissertation Director: Professor Michael R. Greenberg



This study examined daily concentrations of total suspended particulates (TSP) for 1973-1977 at five sites in New Jersey:  Jersey City, Bayonne, Asbury Park, Toms River and Burlington.  The primary purpose of the study was to examine the relationship between TSP and traffic volume; however, sulfur dioxide, temperature, wind speed, carbon monoxide, and other variables were included as controls.  The weekly cycle of TSP, with low weekend values and high weekday values, was of particular interest. Statistical techniques included descriptive statistics, Pearson correlations, factor analysis, and regression analysis.



The variables used in the study were available from existing data sources and have been included, in one form or another, in previous studies of TSP.  If the explanatory variables' values are accurate for the TSP monitoring sites, then this study is unique in that the intercept value in each regression equation is generally equivalent to basic background values assumed to be due to natural emissions and long-range transport.  Thus, the coefficients for the explanatory variables would reflect their natural relationships to each other and not just their statistical relationships.  However, the distances between the TSP sites and the monitoring stations for the other variables cast doubt on the unreliability of the explanatory variables, especially for weather conditions conducive to a build-up of TSP levels.



The final results were five models that show the relationship of key variables to TSP at each site.  Variables that emerged as explanators of TSP in the five equations are traffic volume, precipitation, sulfur dioxide, average wind speed, and a variable representing maximum temperature. Both arithmetic and semi-logarithmic models were developed, but the arithmetic models were dropped due to heteroscedastic residual patterns. No quantifiable industrial emissions variables were available for inclusion in the data set.  Since industrial emissions, like traffic volume may show a weekly cycle, TSP cannot be conclusively tied to traffic volume.  Recommendations for a program to gather additional data are presented.