Multi-Pollutant Mobile Platform Measurements of Air Pollutants and Their Spatial Heterogeneity in the Urban Environment

A mobile monitoring platform developed at NOAA's Air Resources Laboratory (ARL) and the University of Maryland measured a suite of greenhouse gas and pollutant metrics in the American Northeast. This was done to evaluate in situ emissions, local air quality trends, and air pollutant exposure. The study utilized approximately 250 hours of mobile monitoring data collected on major and minor roadway networks in Maryland, Virginia, New York, and Pennsylvania. One-second time resolution measurements of black carbon (BC), carbon monoxide (CO), oxides of nitrogen (NO & NO2), ozone (O3), carbon dioxide (CO2), methane (CH4), and ethane (C2H6) were collected. Additionally, standard meteorological and vehicle parameters were recorded. With traveling speeds of 40–100 km h−1, the observed value represents an average measured over spatial scales of 10–30 m. Localized sources such as vehicles (on and off-road), cooking (food trucks), and industrial emissions lead to hotspots and nonuniform distributions of primary pollutants in urban areas. The spatial heterogeneity of air pollutants demonstrated here illustrates the need to use fine-resolution models to evaluate human exposure and develop pollution control strategies.