For the past week now, parts of northern Utah and western Colorado (including the cities of Salt Lake City and Grand Junction) have been affected by poor air quality. That's because high pressure in the western U.S. has led clear skies, light winds, and a strong temperature inversion to dominate the region.
What's an inversion, you ask? Well, think of it as the atmosphere in an upside-down state. Normally, temperatures get colder when travelling higher up in the air, but under an inversion they increase with altitude. Most importantly, inversions act as a lid that discourages any motion or mixing of air. These stagnant conditions encourage the formation of smog and ground-level ozone (vehicle exhaust, smoke, and any airborne dust or dirt particles)--especially in valleys. And as you know, unhealthy pollution levels can trigger things like asthma attacks, bronchitis, and even cardiac problems.
But residents of the Desert Southwest will soon be able to breathe a sigh of relief! By late weekend, a cold front will enter into the region; it's cold temperatures, winds, and associated snowfall will help clear the air and return healthier conditions.
To monitor air quality conditions in your area, visit Airnow.gov.
Image credit: AIRNow