Smoke from wildfires in the western U.S. and Canada is blanketing much of the continent, including thousands of miles away on the East Coast. And experts say the phenomenon is becoming more common as human-caused global warming stokes bigger and more intense blazes.
Pollution from smoke reached unhealthy levels this week in communities as far east as the Berkshires, Boston and most of New England.
Get used to it, researchers say.
“These fires are going to be burning all summer,” said University of Washington wildfire smoke expert Dan Jaffe. “In terms of bad air quality, everywhere in the country is going to be worse than average this year.”
Growing scientific research points to potential long-term health damage from breathing in microscopic particles of smoke. Authorities have scrambled to better protect people from the harmful effects but face challenges in communicating risk to vulnerable communities and people who live very far from burning forests.
Decades of aggressive firefighting allowed dead trees and other fuels to build up in forests. Now, climate change is drying the landscape, making it easier for fires to ignite and spread, even as more people move into fire-prone areas.
Northern and Southern Berkshires — specifically Dalton, Hancock, Pittsfield, Florida, North Adams, Sandisfield, Great Barrington and South Egremont — were under an air quality action day that expired at noon Tuesday. Last week, an air quality alert was issued for parts of the Berkshires, and New York and Vermont, as well.
The number of unhealthy air quality days recorded in 2021 by pollution monitors nationwide is more than double the number to date in each of the past two years, according to figures provided to The Associated Press by the Environmental Protection Agency. Wildfires likely are driving much of the increase, officials said.
The amount of smoke that wildfires spew stems directly from how much land burns — more than 4,100 square miles in the U.S. and 4,800 square miles in Canada so far in 2021. That is behind the 10-year average for this time of year for both nations, but forecasters warn that conditions could worsen as a severe drought afflicting 85 percent of the West intensifies.
Wildfire smoke contains hundreds of chemical compounds, and many can be harmful in large doses. Health officials use the concentration of smoke particles in the air to gauge the severity of danger to the public.
Scientists link smoke exposure with long-term health problems, including decreased lung function, weakened immune systems and higher rates of flu. In the short term, vulnerable people can be hospitalized and sometimes die from excessive smoke, according to physicians and public health officials.
More than 60 large wildfires are burning out of control across the U.S., including 17 in Montana. The largest — it’s Eastern Oregon’s Bootleg fire — has grown to 624 square miles. That is half the size of Rhode Island, yet, fewer than 200 houses and other structures have been confirmed as lost because the fire is burning in a sparsely populated area.
More than 200 fires are burning in Manitoba and Ontario, according to Canadian officials.
Weather patterns and fire intensity determine who gets hit by smoke. Huge fires generate so much heat that they can produce their own clouds that funnel smoke high into the atmosphere.
“It just carries across the country and slowly spreads out, forming sort of this haze layer in the sky,” said meteorologist Miles Bliss with the National Weather Service in Medford, Ore.
The combined plume from Canada and the U.S. largely passed over parts of the Midwest this week before settling to ground level across an area that stretches from Ohio northeast to New England and south to the Carolinas, air pollution data shows.
Health effects can occur thousands of miles from the flames. The smoke loses its telltale odor but remains a potential hazard, even when it drifts that far, said Jeff Pierce, an atmospheric scientist at Colorado State University.
“It’s certainly unhealthy,” Pierce said of the air along the East Coast in recent days. “If you have asthma or any sort of respiratory condition, you want to be thinking about changing your plans if you’re going to be outside.”
People who live close to fires are more likely to be prepared and take precautions, while those who live farther away unwittingly remain exposed, according to a recent study by Colorado State epidemiologist Sheryl Magzamen and Pierce.
Listen for warnings about smoke and, if advised, avoid outdoor activities to reduce exposure. Keep doors and windows closed, and run an air filter to clean inside air.
Face masks can protect against breathing in smoke. As with COVID-19, most effective are N95 masks, because they are designed to block the smallest particles.
The Associated Press contributed to this report.