Researchers are focusing on the effects of wildfire smoke on air quality, public health, and weather in a new study published in Environmental Science: Atmospheres. The study, led by DRI scientists Siying Lu and Andrey Khlystov, measured air quality in Reno, Nevada over 19 months between 2017 and 2020. During this period, more than 106 wildfires affected the city's air.
Lu explained the research goal: “We know that Reno is frequently impacted by wildfires in summer, so we wanted to compare smoky and non-smoky days and measure the impacts on local air quality.” The study found increased levels of fine aerosols (PM2.5) and carbon monoxide during smoky days. Wildfire smoke contributed significantly to these pollutants during late summer months.
The team used equipment at DRI’s Reno campus to measure atmospheric particle sizes, crucial for understanding their interaction with the atmosphere and human health. Data from a downtown Reno EPA station provided additional information on PM2.5, ozone, carbon monoxide, and other pollutants.
To verify wildfire smoke as the pollution source, researchers used satellite images for visible smoke plumes and fire location data from NASA and NOAA. They also tracked wind patterns using NOAA tools.
Wildfire aerosols have complex weather effects; they can scatter sunlight creating cooling or contain light-absorbing materials causing warming. Larger aerosols may promote cloud formation by acting as nuclei for water vapor condensation.
Khlystov noted distinct particle size differences during fires: “We figured out that the size of particles is quite distinct during fires from a normal day in Reno.”
The study also reported higher carbon monoxide levels on smoky days but similar nitrogen oxides and ozone concentrations compared to average days due to vehicle emissions and sunlight-induced chemical reactions.
“Our research offers one of the most comprehensive looks at how wildfire smoke is affecting air quality in the Western U.S.,” Lu stated.
Lu is developing a machine-learning program to automate identifying wildfire smoke presence for real-time applications in air quality research and public health messaging.