Visitor Vehicle Emissions Study: Summary Report

The U.S. Department of Transportation, John A. Volpe National Transportation Systems Center (Volpe Center), Environmental Measurement and Modeling Division, provided technical support to the National Parks Foundation as a part of a National Park Service (NPS) project to evaluate vehicular emissions in the national parks. A Visitor Vehicular Emissions Study was performed in three California National Parks between August 2002 and April 2003 – Yosemite National Park, Joshua Tree National Park, and Point Reyes National Seashore – in order to collect traffic count, vehicle tracking, meteorological, Inspection and Maintenance Program, and fuel program data. This data was processed through the Environmental Protection Agency’s (EPA) MOBILE6.2 modeling software to produce park-specific emission factors, and weekly traffic count data was used with these emission factors to produce a weekly emissions inventory for each park. Alternative methods involving modal emissions models were also investigated.