title: Observations and model simulations of carbon monoxide emission factors from a California highway.
abstract: A series of twelve intensively monitored 1-hr CO dispersion studies were conducted near Davis, CA, in winter 1996. The experimental equipment included twelve CO sampling ports at elevations up to 50 m, three sonic anemometers, a tethersonde station, aircraft measurements of wind and temperature profile aloft, and a variety of conventional meteorological equipment. The study was designed to explore the role of vehicular exhaust buoyancy during worst-case meteorological conditions, such as low winds oriented in near-parallel alignment with the road during a surface-based nocturnal inversion. From the study, field estimates of the CO emission factor (EF) from a California vehicle fleet were computed using two different methods. The analysis suggests that the CT-EMFAC/EMFAC (EMission FACtor) models currently used to conduct federal conformity modeling significantly overpredict CO emissions for high-speed, free-flowing traffic on California highways.
authors.affiliation: Department of Civil and Environmental Engineering, University of California, Davis, USA. aeheld@ucdavis.edu
authors.forename: A E
authors.initials: AE
authors.lastname: Held
authors.forename: D P
authors.initials: DP
authors.lastname: Chang
authors.forename: D A
authors.initials: DA
authors.lastname: Niemeier
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D002140:California; D002248:Carbon Monoxide / Q000032:analysis*; D003198:Computer Simulation; D008962:Models, Theoretical
chemical_list: D000393:Air Pollutants; D002248:Carbon Monoxide