Mountain air may look and smell clean, but a new study shows high levels of ozone may be polluting the atmosphere at the summit.

The Front Range in Colorado was the subject of an investigation, studying air pollution levels in the region. Researchers wanted to know the concentration of ozone in the mountain range, as well as sources of the gas.

National Center for Atmospheric Research investigators studied the Front Range utilizing aircraft and balloons, along with taking observations from the ground.

Ozone is a molecule of three atoms of oxygen, while atmospheric oxygen, which humans breathe, has two. When it forms in the stratosphere, the gas acts to absorb ultraviolet light, especially UVB rays. This form of energy is known to play a role in the development of skin cancer, and can damage marine life as well as crops.

Ozone is a pollutant at ground level, however, causing respiratory problems and acting to corrode vehicles, buildings and monuments. Pollution forms when volatile organic compounds (VOC) and nitrous oxide (Nox) are released by motor vehicles and factories. These gases combine with oxygen in the air to form ground-level ozone.

"Really, all the way up to the Continental Divide you can find ozone. People (are) thinking you go into the mountains and you breathe the fresh air -- that's not always the case," Gabriele Pfister, from the National Center for Atmospheric Research, said.

Air currents and thermal lift may have acted together to lift the pollutant up the mountain from lower levels where it is produced.

Ozone was tracked as it traveled across the Continental Divide, ending in Grand County, Colo. Some readings taken on the mountains reveal higher concentrations of ground-level ozone than seen in more developed areas.

Flights studying ozone layers in the Front Range began in the middle of July and continued until Aug. 18. Researchers are just beginning to review data collected during the project, and are not yet ready to release detailed conclusions from their study.

"You can see in some cases really kind of a river of pollution spilling over the mountains. And I think that hasn't really been documented well," Frank Flocke, a researcher at NCAR, told the press.

Ozone was recorded at altitudes as high as 16,500 feet. This is 2,000 feet above Longs Peak, the highest mountain in the northern Rockies, and over 11,000 feet higher than Denver.

The Colorado capital occasionally shows concentrations of ozone higher than levels recommended by federal regulators. This new study could assist lawmakers and environmental organizations in determining whether or not current regulations need to be modified.

ⓒ 2021 All rights reserved. Do not reproduce without permission.