Report: Wildfires are a high source of greenhouse gas emissions in Chelan County

Wildfire smoke from recent wild land fire in Chelan County. Photo courtesy: Chelan County.

When big wildfires sweep through Chelan County, they typically burn through thousands of acres of forest and grasslands — sometimes consuming structures along the way, putting people in harm’s way, and generating enough smoke to put some people’s health at risk.

But a less obvious negative also occurs: the massive plumes of smoke contain enough carbon pollution to dwarf all other sources of greenhouse gases generated in the county, according to a recently completed Chelan County greenhouse gas emissions inventory.

In 2023, wildfires released 1.54 million metric tons of carbon dioxide (CO2) into the atmosphere, compared to 337,000 metric tons of CO2 from building energy emissions and 385,000 metric tons of CO2 from transportation emissions, the county inventory found.

In 2022 alone, wildfire emissions in Chelan County totaled 2.2 million metric tons of CO2, which is equivalent to the annual emissions from more than 385,000 gas-powered cars.

Chelan County Natural Resources, in partnership with Sustainable NCW and Our Valley Our Future, hired the consulting firm Parametrix to conduct the study. The analysis considered all significant emissions being generated within the geographic boundaries of Chelan County.

Parametrix determined fuel density and vegetation type strongly influence wildfire emissions. High-intensity fires — such as the 2017 Jack Creek Fire, 2021 Nason Ridge Fire, and the 2023 Airplane Lake fire — burned through dense, overstocked fuels, and significant forest canopy, emitting CO2 that ranged from 147 to 213 metric tons per acre. In contrast, the 2021 Red Apple fire burned through lighter fuels and grassy foothills, producing 16 metric tons of CO2 per acre.

For years, the idea has been that forests can act as an important “carbon sink,” an area that absorbs more carbon than it emits. But as forest fires become larger and happen more often, they emit more carbon stored in the trunks, branches and leaves of their trees as well as in the soil, and reabsorption is no longer assured.

In 2021, emissions from Chelan County wildfires were equivalent to about 7.3 percent of all forest carbon sequestration in Washington state that year. Between 2016 and 2024, average annual emissions in the county equated to approximately 6.4 percent of annual forest carbon sequestration in the state.

“High-severity wildfires release large volumes of carbon dioxide, methane, and nitrous oxide, eroding the long-term climate mitigation value of forests and rangelands,” the Chelan County greenhouse gas emissions report states. “These dynamics are relevant not only to greenhouse gas accounting but also to active

management strategies such as forest thinning, prescribed fire, and biomass utilization — all of which aim to reduce catastrophic fire risk while preserving or enhancing long-term carbon outcomes.”

The complete Chelan County Greenhouse Gas Emission Inventory report can be found here.