The latest bout of air pollution in Utah has prompted government officials and citizens to improve air quality in the region. On Monday, only one county in the state had a healthy air rating, and Salt Lake City, the state capital, experienced particulate counts 82 percent above the federal standard.
The region is a month and a half into its temperature inversion season, which is a weather phenomenon that traps pollutants in the area's valleys. Since the season started, Salt Lake City has seen 21 mandatory action days, which set standards for residents to reduce their emissions.
The graphic below illustrates the difference between a normal air pattern and a thermal inversion: