Evaluation of Mobile Source Emissions and Trends Using Detailed Chemical and Physical MeasurementsEPA Grant Number: R834553
Title: Evaluation of Mobile Source Emissions and Trends Using Detailed Chemical and Physical Measurements
Investigators: Harley, Robert A. , Goldstein, Allen H. , Wood, Ezra
Current Investigators: Harley, Robert A. , Goldstein, Allen H.
Institution: University of California - Berkeley , Aerodyne Research Inc.
Current Institution: University of California - Berkeley
EPA Project Officer: Chung, Serena
Project Period: April 1, 2010 through March 31, 2014
Project Amount: $500,000
RFA: Novel Approaches to Improving Air Pollution Emissions Information (2009) RFA Text | Recipients Lists
Research Category: Particulate Matter , Global Climate Change , Air
This research will characterize trends in mobile source emissions of air pollutants, with emphasis on characterizing distributions of emission factors from individual diesel trucks, in addition to studying fleet-average emissions for both light-duty passenger vehicles and heavy-duty diesel trucks. Both particulate matter and gas-phase emissions will be measured; new instrumentation will be used to characterize particulate matter (PM) emissions.
On-road vehicle emissions will be measured at a highway tunnel near San Francisco, CA. Where feasible, pollutant measurements will be aligned with known exit times of each heavy-duty truck driving through the tunnel. Emission factors will be calculated using carbon balance methods (i.e., by normalizing pollutants to total carbon in the exhaust – mainly CO2). Distributions of CO, NO, NO2, formaldehyde, ethene, PM mass, black carbon (BC), and ultrafine particle number (PN) will be developed from the measured data, with an expected sample size of >500 trucks. BC and PN distributions will be compared to previous data from summer 2006, and correlations among pollutant emission factors from individual engines will be studied. Online two-dimensional gas chromatography will be used with an impaction/thermal desorption sampling technique (2D-TAG) to greatly increase the number of individual organic compounds that can be identified and quantified in the particle phase. A new high resolution time of flight aerosol mass spectrometer (SP2-AMS) that can measure both organic aerosols and refractory black carbon will be used. We will develop emission source profiles for gasoline and diesel engine emissions using 2D-TAG and SP2-AMS data. Fleet-average emission factors for CO, NOx, PM2.5, organic aerosol, and black carbon will be developed and compared to previous measurements made at the same site in 1997 and 2006.
Fleet-average emission factors and distributions of many pollutant emission factors from individual diesel trucks will be measured. New source profiles will characterize organic and black carbon particle emissions at an unprecedented level of detail.