Starting in the winter of 2012, the Uinta Basin Ozone Study (UBOS) launched a wide-ranging research effort into the ways atmospheric chemistry and precursor gases interact to create high levels of wintertime ozone. The study was by far the largest and most complex air quality study ever conducted in Utah. This effort was funded by a number of agencies, including the Uinta Basin Impact Mitigation Special Service District, Western Energy Alliance, Bureau of Land Management’s (BLM) Utah Office, and Environmental Protection Agency (EPA) Region 8. Significant in-kind equipment contributions also came from the State of Utah, National Oceanic and Atmospheric Administration (NOAA), and University of Colorado at Boulder.
Cooperative research work was done by atmospheric research partners from Utah State University, NOAA’s Chemical Sciences and Global Monitoring Divisions, University of Colorado’s Institute of Arctic and Alpine Research, DAQ, EPA, and several other research institutes in the United States and Canada.
Key Findings from the 2012 Study
Unusually warm conditions during the 2011-2012 study period resulted in lack of snow cover and inversions conditions conducive to high ozone levels. While the lack of snow hindered efforts to analyze the photochemical reaction of sunlight on ozone formation, the emissions inventory development during the study provided valuable information.
The 2012 Uinta Basin Winter Ozone and Air Quality Study Final Report included the following key findings:
- Snow cover is a key element in high ozone episodes.
- Analysis of historical weather data indicates that conditions favorable to ozone formation occur during about half of all winter seasons. Severe ozone seasons can be expected to occur about once in four winters.
- Available data suggests that ozone transport is not a major contributor to major ozone events.
- An emissions inventory indicates that oil and gas operations were responsible for 98-99 percent of the volatile organic compounds (VOCs) and 57-61 percent of nitrogen oxides (NOx).
- While VOC emissions are concentrated near the ground, NOx emissions can travel higher into the atmosphere. These vertical differences may impact their contribution to ozone formation.
- Three chemical reaction pathways for ozone formation require further research:
- Sunlight-induced production of nitrous acid (HONO)
- Alkene production on snow surfaces
- Nitryl chloride formation