Why has the air quality been so bad in the Coachella Valley this summer?
On July 31 the air in the Coachella Valley didn’t smell bad, or like wildfire smoke ― just the faint scent of a passing desert thunderstorm. The air did look different, with a blinding white cloud of dust hovering close to the valley floor, blocking views of Mount San Jacinto from Palm Springs. But to the casual observer, this alone might not have been cause for concern. But their weather app, South Coast Air Quality Management District’s website and another online air quality index trackers told a different story.
In fact, Monday’s air quality index in the valley hit 681, well over the threshold of 300 that places air in the “hazardous” level, at which point air pollution can pose a risk to anyone and people are advised to stay indoors and limit activity. The air quality index can be thought of as "a yardstick that runs from 0 to 500," according to the EPA's AirNow. For each possible pollutant, an air quality index of 100 generally corresponds to a concentration that equals the level of the short-term national air quality standard for that pollutant. An air quality index value of 50 or below represents good air quality.
The hazardous air marked the end of a July that brought a combination of bad air quality, extreme heat and wildfires to Riverside County. Both heat and wildfires impact air quality, and both are getting more intense as climate change drives up temperatures.
In total, Coachella Valley residents spent 22 of 31 days of July under some form of air quality advisory, including smoke advisories due to the Rabbit and Bonny fires, ozone advisories during heat waves, and windblown dust advisories, like the storm-driven poor air quality that caused the hazardous air on July 31. The air quality index in July was the first time the air monitor at the Palm Springs Airport measured at hazardous levels since October 2022, and before that the monitor hadn’t recorded a “purple air” or hazardous air day since July 2018.
Air pollution in the Coachella Valley
There are three main air pollution concerns in the Coachella Valley: high levels of ozone or smog, most of which comes from the Inland Empire and Greater Los Angeles and which often peaks on the hottest days of the year and is higher during afternoon hours; larger particulate matter from windblown dust; and finer particulate matter from wildfire smoke, which is the rarest of the three to impact the valley.
Palm Springs has experienced a total of seven hazardous air quality days since 2000, and all of those have been caused by dust, according to Scott Epstein, the program supervisor of air quality assessment for the South Coast Air Quality Management District.
“I think the take-home this past month has been pretty rough for air quality in Southern California, in general, with all the heat we’ve had, with ozone, with this dust storm (this week), and fires,” said Scott Epstein, the program supervisor of air quality assessment for the South Coast Air Quality Management District.
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How climate change is impacting air quality
Riverside County has long had some of the worst air quality in the nation, ranking eighth out of U.S. counties for annual particulate matter and second for ozone in the American Lung Association’s most recent State of the Air Report. And even as gains on air quality have been made through tighter emissions regulations and electric vehicle adoption, the impacts of climate change are undoing some of those efforts in Western states through more frequent and intense wildfires and heat waves.
"For decades we've seen positive trends on progress of clean air efforts in California, with major reductions in harmful pollutants as an outcome of the strong policies and investments that California and local air districts have put forward over the years," said Will Barrett, national senior director of clean air advocacy for the American Lung Association, which launched its annual State of the Air report in 2000. "But at the same time as we've seen all this progress, we know we have a long way to go. And we know that climate change is making the job of keeping our air clean, and building on that momentum much more difficult."
The American Lung Association has tracked a dramatic spike in the number of unhealthy or hazardous air days over the past five years, with wildfires in the western U.S. "a major contributing factor to the increasing number of days and places with unhealthy levels of particle pollution" and creating "a widening disparity between air quality in eastern and western states."
"One of the key things that we're seeing is the conditions for poor air quality becoming amplified, whether that's extreme heat driving up ozone or increasing drought conditions and hotter, drier weather driving extreme wildfire episodes. These are, you know, really symptoms of our climate health crisis. And it has a dramatic impact on how much more difficult it is to keep our air clean," said Barrett.
How to stay safe on bad air days
With high temperatures and potential wildfire weather in the forecast this summer, here's what you need to know about staying safe on bad air days, according to Epstein:
Stay up to date on air quality by checking online at South Coast AWMD's website, since bad air might not always be apparent by the smell of smoke or another obvious factor.
The main goal when air quality is poor is to minimize how much air pollution you're exposed too, by minimizing outdoor physical activity.
Remain inside with windows and doors closed if possible, and run an air conditioner with a high-efficiency filter or air purifier if available.
If temperatures allow, avoid using a swamp cooler because it brings outside air inside.
People with pre-existing conditions, heart and lung issues, children, older adults, and pregnant people should be extra careful, as they are more susceptible to the impacts of air pollution.
This article originally appeared on Palm Springs Desert Sun: Why has the air quality been so bad in the Coachella Valley?
