Wildfire smoke blankets large parts of the United States as Pacific Northwest fires persist
More than 40 active wildfires in Oregon and Washington have generated a smoke plume that reached as far as Florida, prompting air quality advisories across the western and central U.S.
Smoke from dozens of wildfires burning in the Pacific Northwest continued to create hazy skies and unhealthy conditions on Wednesday for a broad swath of the United States. While air quality in parts of Oregon and Idaho improved slightly, both states still advised residents to limit outdoor exposure.
As of Wednesday morning, 45 large uncontained fires were active in Oregon and Washington, together with smaller ignitions, having burned over 1.8 million acres. More than 17 uncontrolled fires were also reported in British Columbia. The worst air quality that day was recorded near Boise, Idaho, where particulate matter levels were just below the “very unhealthy” threshold, and eastern Oregon and southern Idaho experienced generally unhealthy conditions.
Forecasters expected the plume to travel northward into Montana, the Dakotas and Minnesota before moving southeast toward the Midwest and parts of the South, with some smoke reaching Florida. Most of the smoke at that distance was expected to remain aloft and have limited impact on ground-level air quality.
The severity of this year’s fire season follows a warm winter that left forests drier than usual and reduced mountain snowpack, combined with recent prolonged heat waves that further desiccated vegetation. >"The conspicuous overlap between record-breaking warmth, dryness, and/or low snowpack and these fires is simply not a coincidence," climate scientist Daniel Swain wrote on social media.
Swain added that while it is impossible to attribute any single fire to climate change, the broader warming trend is a growing factor in extreme fire behavior. >"Climate change is certainly not the only factor at play in any of these regions. But it's also a rapidly growing contributor, and in some of these 'edge case' extremes is likely even a leading one," he said.
Health officials warned that wildfire smoke contains fine particulate matter that can penetrate deep into the lungs and enter the bloodstream, posing risks to the cardiovascular and nervous systems. >"Fine particulate matter from wildfire smoke is particularly dangerous because it can penetrate deep into the lungs and enter the bloodstream, potentially causing damage to multiple body systems," Stanford research scientist Jessica Yu told a panel last year.
Experts recommended limiting outdoor activities, using N95 or equivalent respirators when exposure is unavoidable, keeping windows and doors closed, and employing indoor air filtration or recirculating air-conditioning systems to reduce indoor pollutant levels.