Spatiotemporal Comparison of Finely-Resolved Emissions and Concentrations of Carbon Dioxide in Salt Lake City, Utah

This study addresses the need for robust highly-resolved emissions and concentration data required for planning purposes and policy development aimed at managing pollutant sources. Adverse health effects resulting from urban pollution exposure are dependent on proximity to emission sources and atmospheric mixing, necessitating models with high spatial and temporal resolution. As urban emission sources co-emit carbon dioxide (CO₂) and criteria pollutants (CAPs), efforts to reduce specific pollutants would synergistically reduce others. We present emissions inventories and modeled concentrations for CO₂ and compare the resulting concentrations against stationary and mobile measurement data and present a systematic quantification of uncertainties. The emissions inventory for CO₂ is based on the Hestia data inventory that resolves emissions at an hourly, building and road link resolution as well as hourly gridded emissions with a 0.002^o x 0.002^o spatial resolution. The Stochastic Time-Inverted Lagrangian Transport (STILT) model was used to estimate CO₂ concentrations resulting from Hestia and biogenic CO₂ fluxes. The resulting modeled concentrations were compared against stationary measurements in the Salt Lake City area. The comparison between modeled and measured concentrations highlights spatial locations and hours of high variability and uncertainty.