Several Mountain West states are experiencing bouts of poor air quality this summer. There are several contributing factors, including smoke from wildfires and auto emissions. The sunlight also plays a big role.
Particulate matter from those fires and ground-level, human caused ozone from cars are the specific pollutants in the air, a problem exacerbated during the long summer days because of ultraviolet rays emitted by the intense sunlight.
Several state health agencies in the region have issued air quality advisories.
Ozone is a “regional issue,” according to Kevin MacDonald, public information officer with the Clark County Division of Air Quality in Nevada, one of the counties that has issued an advisory.
“One of the issues with ozone is that pollutants will travel like wildfire smoke, and this all plays a factor in what we call this ‘stew’ that forms ozone,” he said.
Ground-level ozone pollution increases during the summer months, he added.
“If you look at a 24-hour day and look up data from one of our monitoring stations, you'll see ozone is going to be low in the morning and then, typically, around 2- to 3 O’clock is when it’s reaching its peak,” MacDonald said. “The sunlight is helping to cook that ozone.”
Southern Nevada is under an ozone advisory through the end of August. A particulate advisory has also been issued due to wildfires. Clark County has exceeded safe ozone levels on at least 14 days this summer.
This week, the federal Environmental Protection Agency forecasted ongoing bad air quality in parts of Nevada. The forecast also said areas in Arizona, Colorado, Idaho, New Mexico, Utah, and Wyoming should expect poor air quality in the days ahead.
That has led state and local officials in several states to recommend that people take proactive measures, such as driving less, refueling their vehicles in the evenings to minimize the evaporation of gas fumes, and reducing household energy use.
More: Get real-time air quality information and forecasts from the EPA’s Air Now webpage.
This story was produced by the Mountain West News Bureau, a collaboration between Wyoming Public Media, Nevada Public Radio (KNPR) in Las Vegas, Boise State Public Radio in Idaho, KUNR in Nevada, KUNC in Colorado and KANW in New Mexico, with support from affiliate stations across the region. Funding for the Mountain West News Bureau is provided in part by the Corporation for Public Broadcasting.