![]() Measurements form the basis of our understanding of air pollution scientists, regulators, and the public use these measurements to understand atmospheric chemistry, determine air quality levels, link concentrations to health effects, and evaluate advanced air quality models. The agreement between the parked car estimates of uncertainty and that measured during the mobile collocations (at the lower quantiles) provides evidence that on-road collocation while parked could be sufficient for estimating measurement uncertainties of a mobile platform, even when extended to the moving environment. We assert that the difference between the actual and theoretical distributions is due to real spatial variability between pollutants. The distribution of mobile measurements agreed well with the theoretical uncertainty distribution at the lower end of the distribution for O 3, NO 2, and PN. For the moving collocation periods, we compared the distribution of 1-σ standard deviations among the 3 cars to the estimated distribution assuming only measurement uncertainty (precision and bias). Bias was assessed by measurements obtained from parked cars using the standard deviation of median values over a collocated measurement period, as well as by Passing-Bablok regression statistics while the cars were moving and collocated. ![]() We used the median absolute deviation (MAD) to estimate instrument precision from outdoor, parked collocations. Augwas dedicated to parked and moving collocations among the three cars, allowing an assessment of measurement precision and bias. They were driven throughout the greater Denver metropolitan area between Jand August 14, 2014, measuring ozone (O 3), nitrogen dioxide (NO 2), nitric oxide (NO), black carbon (BC), and size-resolve particle number counts (PN) between 0.3 μm and 5.0 μm diameter. mobile air pollution measurement and data acquisition platform installed on three Google Street View cars. We used robust statistical methods to assess mobile platform performance using data collected with the Aclima Inc. Characterizing instrument performance in the mobile context is challenging, but necessary to analyze and interpret the resulting data. Mobile mapping of air pollution has the potential to provide pollutant concentration data at unprecedented spatial scales. ![]()
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