Historic Wildfire Pollution Sweeps Across America

Historic Wildfire Pollution Sweeps Across America

Tuesday ranked as the third-worst day in US history for exposure to wildfire smoke on a population-weighted basis, according to a rapid analysis conducted by Stanford researchers.

Wednesday is set to be among the worst two days for wildfire smoke in American history, the researchers said.

Even prior to this week, the East Coast experienced the worst wildfire-driven air pollution in 2021, surpassing levels faced by those living in the West.

The new analysis looked at two variables: how intense the “dose” of wildfire smoke was, and how many people it affected.

On what days in history is a statistically random American likely to breathe the most wildfire smoke into their lungs? Tuesday and Wednesday of this week, it found.

The finding also clarifies how much wildfire smoke the East Coast has already faced this year, with New York, Boston, D.C., and Detroit among the cities most affected.

Wildfire-driven air pollution reached higher concentrations in some parts of the West in 2020 and 2021, but it never affected so many people living in such a densely populated area.

Marshall Burke, an economist and sustainability professor at Stanford who led the research, said, “It’s pretty off the charts."

"It’s pretty historic. We’re talking about the most populated parts of the country just getting hammered.”

The team cannot formally establish that Wednesday was among the worst days in American history until records become available.

The intensity of pollution observed virtually guarantees that Wednesday is worse than Tuesday, Burke said.

The analysis highlights the implications of such pollution events for the future, with wildfires expanding in size and the American population growing.