You are here:
CO-DEPENDENCIES OF REACTIVE AIR TOXIC AND CRITERIA POLLUTANTS ON EMISSION REDUCTIONS
Citation:
LUECKEN, D. J. AND A. CIMORELLI. CO-DEPENDENCIES OF REACTIVE AIR TOXIC AND CRITERIA POLLUTANTS ON EMISSION REDUCTIONS. JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION. Air & Waste Management Association, Pittsburgh, PA, 58(5):693-701, (2008).
Impact/Purpose:
The National Exposure Research Laboratory's (NERL's) Atmospheric Modeling Division (AMD) conducts research in support of EPA’s mission to protect human health and the environment. AMD's research program is engaged in developing and evaluating predictive atmospheric models on all spatial and temporal scales for forecasting the Nation's air quality and for assessing changes in air quality and air pollutant exposures, as affected by changes in ecosystem management and regulatory decisions. AMD is responsible for providing a sound scientific and technical basis for regulatory policies based on air quality models to improve ambient air quality. The models developed by AMD are being used by EPA, NOAA, and the air pollution community in understanding and forecasting not only the magnitude of the air pollution problem, but also in developing emission control policies and regulations for air quality improvements.
Description:
It is important to understand the effect of emission controls on the concentrations of ozone, PM2.5, and hazardous air pollutants simultaneously, in order to evaluate the full range of both health related and economic effects. Until recently, the capability of simultaneously evaluating interrelated atmospheric pollutants ("one atmosphere" analysis) was unavailable to air quality managers. In this work, we use the Community Multi-Scale Air Quality (CMAQ) modeling system to examine the potential effect of several control strategies on concentrations of ozone, PM2.5, and four important hazardous air pollutants: formaldehyde, acetaldehyde, acrolein and benzene. We examine the effects of these control scenarios over a domain centered on the metropolitan Philadelphia area, for 12-day episodes in July and January 2001. While NOx controls alone are generally a benefit for ozone and PM2.5 concentrations, they are predicted to have only a small effect on formaldehyde, slightly increase acetaldehyde and acrolein concentrations, and have no effect on benzene in the summer episode. Concentrations of all pollutants except benzene in this simulation increase slightly with NOx controls in the winter episode. VOC controls alone are found to have a small effect on ozone and PM2.5, a less than linear effect on decreasing the aldehydes, and an approximately linear effect on acrolein and benzene in summer, but a slightly larger than linear effect on aldehydes and acrolein in winter. Chemistry effects in upper layers of the model sometimes affect the surface-level concentrations. The response to both VOC and NOx controls is largely a combination of response to each separately. These simulations indicate the difficulty in assessing how toxic air pollutants might or might not respond to emission reductions aimed at decreasing criteria pollutants such as ozone and PM2.5.