Play Live Radio
Next Up:
0:00
0:00
0:00 0:00
Available On Air Stations

Wildfire smoke can change the atmosphere, even a week later

A lone couple takes in a smoky view at Portland's Skidmore Bluffs in September 2020. Even after wildfire smoke seems to clear, it leaves behind chemicals that can impact the climate for days.
Claudia Meza
A lone couple takes in a smoky view at Portland's Skidmore Bluffs in September 2020. Even after wildfire smoke seems to clear, it leaves behind chemicals that can impact the climate for days.

Smoky skies can harm our lungs and the environment. But even when the sky seems to clear of smoke, authors of a new study say leftover smoke particulates can continue to impact the atmosphere for more than a week.

The study, published in the journal Environmental Science and Technology, looks at data from the Mount Bachelor Observatory in the summer of 2019. Though wildfire was calm that year, researchers found wildfire smoke particulates from Northern California and even some from as far away as Siberia. Those particulates were more than a week old and still contained climate-changing chemicals.

Qi Zhang — a professor with the University of California, Davis, who worked on the study — said the air at the observatory was, “kind of like a typical pristine, remote atmospheric condition.”

“However, if we look at the atmospheric chemistry measurements, we see clear signals for a wildfire emission,” Zhang said.

She said this information is crucial in knowing more about the impacts of wildfire smoke, even when there doesn’t appear to be any around.

The chemicals in old wildfire smoke can change the temperature by scattering or absorbing solar radiation. They can also seed clouds to produce rain or snow.

In the study, researchers found that particulate matter concentrations within old wildfire smoke were low, but oxidized aerosols from burning biomass — like trees and shrubs — were found throughout the samples. These aerosols were larger in old smoke samples compared to those found after a fire starts.

Copyright 2022 Oregon Public Broadcasting. To see more, visit Oregon Public Broadcasting.

April Ehrlich began freelancing for Jefferson Public Radio in the fall of 2016, and then officially joined the team as its Morning Edition Host and a Jefferson Exchange producer in August 2017.