In addition to particulate matter, another leading indicator of air quality is ozone (O3) which is the primary consitutent of smog. Ozone develops from a reaction between volatile organic compounds (VOCs) and oxides of nitrogen (NOx) in sunlight. The presence of these precursors for Ozone are emitted by motor vehicles, power plants, industrial sites and some natural sources. Epidemiological studies have linked associations between exposure to Ozone and a variety of respiratory health outcomes including a decrease in lung function and increased inflammation resulting in hospital visits 1. Ozone concentration is measured in parts per billion (ppb) in the air for the summer seasonal average over an 8-hour daily period.
The source data for this modeled Ozone concentration in the air was gathered from the U.S. Environmental Protection Agency (U.S. EPA) Environmental Justice (EJ) Screen database. Estimates are based on public monitoring data using the Community Multi-scale Air Quality (CMAQ) data. Census tract estimates for modeled Ozone concentration were based on 2013 monitoring data and were assigned to Census block groups. A limited number of U.S. air quality monitors have suitable data, so modeled estimates are required to provide national coverage using a Bayesian space-time down scaling fusion model approach.2 Ozone concentration is measured in parts per billion (ppb) in the air for the summer seasonal (May through September) average of a daily 8-hour period.
The MSA level value is the unweighted mean of the values of all block groups in the MSA.
- Ozoning concentration = Modeled concentration of Ozone.
This indicator was calculated by the U.S. Environmental Protection Agency (EPA) using data from the sources listed below.
- Bell, M. L., Zanobetti, A., & Dominici, F. (2014). Who is More Affected by Ozone Pollution? A Systematic Review and Meta-Analysis. American Journal of Epidemiology, 180(1), 15-28.
- Fann, N., Lamson, A. D., Anenberg, S. C., Wesson, K., Risley, D., & Hubbell, B. J. (2012). Estimating the National Public Health Burden Associated with Exposure to Ambient PM2.5 and Ozone. Risk Analysis, 32(1), 81-95.
- Fann, N., & Risley, D. (2011). The Public Health Context for PM2.5 and Ozone Air Quality Trends. Air Quality, Atmosphere & Health, 6(1), 1-11.
Byun, D., & Schere, K. (2006). Review of the Governing Equations, Computational Algorithms, and Other Components of the Models-3 Community Multiscale Air Quality (CMAQ) Modeling System. Applied Mechanics Review, 59, 51-77.