Breathing smoke and dust in the Fresno-area? Here’s the updated air quality forecast
An air quality alert is in place for windblown wildfire smoke in Madera, Fresno, Tulare, Kern and Kings counties, just as the region was seeing relief from dust carried by wind.
Hazy and dusty conditions caused by gusty winds created moderate air quality on Sunday and Monday that improved in some areas by Tuesday afternoon. Instead of relief, northeasterly winds are expected to increase local smoke impacts from the Creek Fire, beginning Tuesday afternoon, according to Jon Klassen with the San Joaquin Valley Air Pollution Control District.
“We’re expecting conditions to deteriorate over the next few days,” Klassen said. “We are expecting air quality, unfortunately, to get a little worse (this week).”
A National Weather Service forecast predicted heavy smoke over Fresno and Madera counties beginning Tuesday afternoon, which didn’t materialize as severely as anticipated. There was smoke, but not as thick as expected.
“That’s because the smoke model used assumes the same amount of burning will occur the next day as the previous,” said James Dudley, a meteorologist with the weather service in Hanford. “So today, with lighter winds on the fire, the amount of new burning did not happen. Thus, far less smoke.”
Short-term exposure to air pollution creates an increased risk of respiratory and cardiovascular illness in the days following the exposure, according to several scientific studies that reviewed hospital admission data after bad air days.
Cloth and paper masks used to prevent the spread of COVID-19 do not protect against the potentially harmful effects of air pollution and smoke.
Stay indoors if you see smoke or dust to avoid potential health risks. The risk is higher for children, adults over 65 and anyone with compromised respiratory or cardiovascular systems, such as asthma or a history of stroke or heart attack.
While both dust and smoke affect air quality, health risks are more severe from wildfire smoke.
The difference is the size of the particulate matter in the air. Smoke generally creates PM 2.5 — particles that are smaller in diameter than 2.5 microns — and dust particles tend to be a little larger, smaller than PM 10. Both are a health risk, but PM 2.5 is more dangerous because the particles are small enough to enter the bloodstream.
Where is air quality unhealthy?
Air quality levels weren’t the same everywhere on Tuesday. Some neighborhoods registered air pollution that is unhealthy for sensitive people all day, according to monitoring data available at airnow.gov.
The communities of Modesto, Madera and Santa Rosa Rancheria, southwest of Lemoore, experienced levels of PM 10, tiny particles with a diameter of 10 microns or less, that are unhealthy for sensitive groups, including children and seniors.
Each of those areas saw an air quality index over 110. Anything over 100 is considered unhealthy for sensitive people.
The source of the particulate matter was likely windblown dust, Klassen said.
It’s common for some agricultural burning to affect air quality this time of year.
Anyone who sees agricultural burning is asked to report it to the APCD, as currently no agricultural burning is allowed anywhere in the San Joaquin Valley, according to Jamie Holt with the air district.
Some neighborhoods may be impacted by dust from almond harvesting.
Farmers are required to minimize dust emissions, and staff with the APCD are working with farmers to reduce effects to sensitive communities like schools and residential developments by timing harvesting at certain times, Holt said. The APCD has $10 million in grant funds available for farmers to purchase equipment to reduce dust emissions.
How to check neighborhood-level air quality
Air quality can be different across neighborhoods in the same town because of wind patterns and proximity to agricultural operations and other sources of pollution, like freeways with heavy truck traffic.
Four different tools provide helpful information.
The San Joquin Valley Air Pollution Control District’ RAAN search tool provides real-time data on smog and PM 2.5 by entering an address in the search bar. You can also sign up to receive air quality alerts. The tool does not currently provide PM 10 data, which staff said may change by the end of the year.
The airnow.gov interactive map provides real-time data for smog, PM 2.5 and PM 10 from local monitors across the country. It is managed by the U.S. Environmental Protection Agency.
For more localized neighborhood data, use the PurpleAir.com map that compiles crowd-sourced data from private, consumer monitors. Or, use the similar IQAir.com that pulls data from AirVisual consumer monitors.
This story was originally published October 27, 2020 at 5:19 PM with the headline "Breathing smoke and dust in the Fresno-area? Here’s the updated air quality forecast."
