Air Quality | Tracking | NCEH | CDC

Monitor + Modeled Air Data
After careful study, EPA and CDC found that air pollution modeled predictions are very similar to actual monitor data in areas where the two can be compared. In some areas, the modeled data underestimates or overestimates the air pollutant concentration levels when compared to the Air Quality System (AQS) monitoring data. Therefore, the best way to use modeled air data is in conjunction with actual monitoring data. On the Tracking Network, both AQS and modeled datasets are available to track possible exposures to ozone and PM2.5, evaluate health impacts, conduct analytical studies linking health effects and the environment, and guide public health actions.

• Ozone Days Above Regulatory Standard
  The number of days in which the daily maximum 8-hour average ozone concentration exceeds a standard provides an indication of short-term spikes in ozone concentrations. This may give you an idea of how many days per year you may be exposed to unhealthy levels of ozone.
• PM2.5 – Days Above Regulatory Standard
  These data help summarize short-term trends in particle pollution concentrations. This may give you an idea of how many days per year you may be exposed to unhealthy levels of particulate matter.
• Annual PM2.5 – Level
  These data help summarize long-term trends in particle pollution concentrations. This will give you an idea of what the yearly level of PM2.5 is in an area.

Health Impacts of Fine Particles in Air: Mortality Benefits Associated with Reducing PM2.5 Concentration Levels
To calculate these data, CDC is using EPA’s BenMAP with modeled air data for fine particulates, death data from CDC’s National Center for Health Statistics, population data from the U.S. Census Bureau, and information from scientific literature about the relationship between change in air pollution and how that influences health effects. These data summarize the estimated number of deaths prevented and percent change in deaths associated with lowering PM2.5 concentration levels. The Tracking Network lets the user sort many results by categories of county-level sociodemographic variables such as percentage of population in poverty, percentage of adult smokers, population density, and more.

Air Toxics
Data from EPA’s National-Scale Air Toxics Assessment (NATA) are used to develop the air toxics indicators for the Tracking Network. Air toxics measures can be used to

• prioritize emission sources as potential targets for risk reduction activities and further study,
• identify locations of interest for further investigation, and
• show the geographic distribution of air toxics.

Wildfires
This indicator displays locations of predicted surface smoke concentrations from wildfires that are layered on top of county- and census tract-level measures of access to care and social vulnerability, health status, annual air quality levels, or population characteristics

Forecasted Air Quality
CDC’s Environmental Public Health Tracking Program collaborated with the National Aeronautics and Space Administration’s (NASA) Goddard Space Flight Center to develop this data set. The forecasts included in this indicator can help decision-makers and other stakeholders anticipate harmful air pollution exposures several days in advance. This composition forecast data set is a research-grade product and should be used only in circumstances where substantial error in the estimates does not pose a significant threat to human health or other operational priorities.