Uncertainty and Variability in Social Costs for Air Quality

Presenter
Elisabeth Gilmore, Assistant Professor
School of Public Policy, University of Maryland, College Park

Abstract
Choosing between alternative products, processes and policies requires credible information on both their private and social costs. For air quality, an impact pathway approach, which traces the emissions through to the monetization of the associated effects, is frequently employed to estimate this social cost. An important step in this process is transforming the emissions to their equivalent ambient concentrations. The assumptions in the air quality models, however, are rarely evaluated and may introduce error into the reduced form literature values. Here, we develop new estimates of the social cost for air emissions in $/ton for generic area and point sources in US urban and rural locations. We use a ‘state of science’ 3-D chemical transport model, the Particulate Matter Comprehensive Air Quality Model with extensions (PMCAMx). By using this model, we attempt to better account for variability and inherent uncertainties in the effects of emissions as it relates to precursor species, season, location and source type in the model to better constrain the value of particulate matter control in terms of social cost. We calculate social costs that differ from other literature values by a factor of two to more than ten for both reactive and non-reactive compounds. This suggests that model variability in transport and chemistry can have an important influence on the estimates. Our results recommend caution in the use of literature values for the social cost of air quality emissions for benefit-cost analysis and externality pricing.

Date
Thursday, September 20, 2012
12:00 - 1:30 p.m. Lunch will be provided. Location
7th Floor Conference Room
1616 P St. NW
Washington, D.C. 20036 All seminars will be in the 7th Floor Conference Room at RFF, 1616 P Street NW. Attendance is open, but involves pre-registration no later than two days prior to the event. For questions and to register to an event, please contact Khadija Hill at [email protected] (tel. 202-328-5174). Updates to our academic seminars schedule will be posted at www.rff.org/academicseminarseries.