Results: We found substantial variations in traffic and noise with in and between cities.Total number of
vehicle count sexplaineda substantial a mount of variationin 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 wereuseda smodel input.Weaker correlations were
found when MPO traffic data was usedas model input.