Results: We found substantial variations in traffic and noise with in and between cities.Total number of
vehicle count sexplaineda substantial a mount of variation in measured ambient noise in Atlanta(78%),
Los Angeles(58%),and NewYorkCity(62%).Modeled noise levels were moderately correlated with
measured noise levels when observed traffic counts were used as model input.Weaker correlations were
found when MPO traffic data was used as model input.