All that black smoke you see floating up from a wildfire — it’s full of small particles that are bad for your lungs and heart.
It turns out, the small particles are a lot worse than researchers previously thought. A new study found there are three times as much pollution in wildfire smoke plumes than predicted from earlier estimates.
“If you live in some remote areas in the West, your air quality could end up being pretty bad (during wildfire season), although you’re away from traditional pollution sources, due to all the particulate matter from the wildfires,” said study co-author Greg Huey, from Georgia Institute of Technology.
This sort of particulate matter is bad for people with asthma or heart conditions.
The researchers say it’s a big contributor to poor air quality in the Western United States.
The research involved specially outfitted planes — flying laboratories of sorts decked out with loads of instruments — through wildfire plumes during the 2013 wildfire season. They sampled smoke from the Big Windy Complex in Southern Oregon, Colokum Tarps near Wenatchee, Washington, and the Rim Fire, the third largest fire in California’s history.
The planes were provided by NASA and the Department of Energy.
Flying through the smoke, and even over smaller agricultural burns, “You see just huge amounts of (air pollution) we just don’t see anymore in the United States,” Huey said — because air pollution controls have improved air quality.
Air pollution like methanol, benzene, ozone precursors and noxious emissions were much higher than if a plane flew around a power plant, said Xiaoxi Liu, then a graduate student at Georgia Tech and the lead author of the study.
“That’s impressive, and that triggered me to think about the impact of biomass burning,” Liu said.
Soaring above the fires and through the smoke, the flights could get bumpy, although scientists lucked out on some turbulence because this research plane was larger than most.
“You fly though one of these plumes, and you can smell the smoke in the cabin,” Huey said.
The Environmental Protection Agency collected earlier data on smoke plumes, but that data came from prescribed burns. This was the first time researchers were able to collect this amount of data from wildfires as they burned.
Wildfires burn more fuel per acre than prescribed burns. Researchers say that’s one reason there's more pollution from wildfire smoke than from prescribed burn smoke.
Prescribed burns are fires lit by land managers to benefit the ecosystem and help prevent massive wildfires.
While prescribed burning does release smoke into the air, it’s controlled.
“Wildfires can happen at any time. They can happen when the wind is blowing towards a major city, which would expose a lot of people,” said Bob Yokelson, a co-author at the University of Montana.
The study authors say land managers need to consider using prescribed burns to address air quality issues from wildfires.
“Biomass burning is certainly a major factor that influences climate change, air quality, and human health,” Liu said. “There are still a lot of unknowns and uncertainties in estimating the impact of biomass burning.”
Next, researchers want to look at fires with different kinds of fuels, agricultural fires to look at a range of smoke.
NASA funded the study. It’s published in the Journal of Geophysical Research: Atmospheres.