Fires in the Pacific Northwest have altered air pollution patterns

Fires across North America have become larger and more intense as a result of increased development, poor land-use policies, and climate change. A new paper published in the journal Nature Communications sought to look more closely at how this change in fire intensity affects air pollution. 

A research team led by the National Center for Atmospheric Research (NCAR) discovered that harmful pollutants from fires in the Pacific Northwest affect places far away, like Colorado. 

The fires in the Pacific Northwest are changing the seasonal air pollution pattern, causing a pollution spike in August. 

“Wildfire emissions have increased so substantially that they’re changing the annual pattern of air quality across North America,” said study lead author and NCAR scientist Rebecca Buchholz. “It’s quite clear that there is a new peak of air pollution in August that didn’t used (sic) to exist.”

Global inventories of wildfires and satellite-based observations of atmospheric chemistry enabled scientists to follow wildfire emissions in the Pacific Northwest, the central United States, and the Northeast from 2002 through 2018.

To measure the level of pollution, the researchers calculated carbon monoxide levels because this gas is an indicator of other air pollutants. They discovered that carbon monoxide increased in August, which is the peak burning season in the Pacific Northwest. 

The experts also determined that the increase in carbon monoxide was not because of pollution blowing in from Asia, fires in other regions of North America, or an increase in fossil fuel emissions.  

“Multiple lines of evidence point to the worsening wildfires in the Pacific Northwest as the cause of degraded air quality,” said Buchholz. “It’s particularly unfortunate that these fires are undermining the gains that society has made in reducing pollution overall.”

The increase in fires in the Pacific Northwest could impact people all over the United States. The research shows the pollutants could affect four million people in the Pacific Northwest, 23 million in the Central U.S., and 72 million in the Northeast.

Moreover, the team found that from 2012 to 2018, deaths due to respiratory illness in Colorado increased when fires in the Pacific Northwest, not Colorado, created more emissions in August. 

“It’s clear that more research is needed into the health implications of all this smoke,” concluded Buchholz. “We may already be seeing the consequences of these fires on the health of residents who live hundreds or even thousands of miles downwind.”

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By Erin Moody , Earth.com Staff Writer