In June, EPA Administrator Scott Pruitt announced that the Trump administration would give states an extra year to comply stricter ozone standards enacted by the Obama administration in 2015. On Aug. 2, Pruitt again reversed course, saying the rule would take effect after all. That’s good news for people who breathe. It’s also good for our tourism economy dependent upon clear skies and viewsheds.
The issue is tremendously complicated. Ozone in the stratosphere provides a shield from ultraviolet radiation. That beneficial ozone layer has been partially destroyed by manmade chemicals, although the hole in the ozone layer is shrinking.
At ground level, ozone is a harmful pollutant that can trigger a variety of health problems, especially for children, the elderly, and people of all ages who have asthma or other lung diseases. Ground-level ozone occurs when pollutants emitted by cars, industrial plants and other sources — in this region, particularly coal-fired power plants — chemically react in the presence of sunlight. The result is smog.
But, in another layer of complexity, ozone targets are more difficult to meet for high-elevations cities, including Colorado’s Front Range, and in desert states like Arizona with a high level of naturally occurring ozone. Wind can move ozone over long distances.