Inversions happen when a layer of warmer air acts as a lid, and it caps the cooler air below. Just as the cold air can’t escape, neither can the pollution. (As Cache Valley residents know, this polluted air can’t leave the valley until after a storm or heavy winds blow through.)
Experts tell us we can’t control the inversion, but we can control the emissions we release into the air.
Those concerned with their health during times of inversion have found sites like air.utah.gov to check the latest air quality readings.
“What you find there is a chart listing levels of PM 2.5 and we measure them in something similar to parts per million,” said Josh Greer, environmental scientist with the Bear River Health Department. “That refers to the numbers of these tiny particles in the air that are 2.5 microns or smaller that can get deep into our lungs and cause us some trouble.”
Another prominent reading lists the number of molecules per million of ozone, a major air pollutant which can also trigger negative health results.
“What we see in Cache County is that approximately 50 percent of pollution that adds to our PM 2.5 comes from vehicles and the vast majority of the rest comes from pollution resulting from heating our homes and running our businesses,” said Greer.
He said Utah Department of Air Quality records indicate we typically hit inversion season around November, continuing into March.
“Depending on the year we might have two, three and even four weeks where we experience a pretty heavy inversion.”
Greer said he is confident that over time Utah’s air will continue to become cleaner because of many good controls now in place including the introduction of what are called Tier 3 vehicles that are burning cleaner fuel which means less pollution will be coming out of tail pipes.