Air Quality Issues - Ozone

Modeling and data analyses have consistently shown that NOx reductions are far more effective at reducing ozone in DFW than VOC reductions. The model's response to anthropogenic (man-made) VOC reductions is weak and linear, whereas the response to NOx reductions gets stronger with larger NOx reductions. A modeling test removed 75% of anthropogenic VOCs across all sources with little impact on modeled ozone concentrations.

2008 biogenic emissions are 66% of the total VOCs in the 23-county area. Oil and gas VOC emissions for the same area are 14% of the total VOCs. Thus, even if VOC emissions from oil and gas activities were controlled, there would be enough biogenic VOCs to carry ozone reactions forward.

The majority of Barnett Shale sources are north and west of the DFW nonattainment area. 80% of the time between May and October (months with weather conditions most conducive to ozone formation) winds blow emissions from the Barnett Shale away from the DFW area, and thus, from that perspective are also not expected to significantly affect ozone in the DFW area.

Related information: DFW and the State Implementation Plan