Davis

Driven by climate change, forests laden with fuel, historic drought and heat waves, wildfires in the US West are spreading smoky air to millions of people, even those who live far from where the fires burn. The problem is becoming so pronounced that some television weather forecasters in California now include “smoke casts,” in their reports, displaying models that predict, like a weather forecast, where smoky air from a wildfire will travel days into the future.

Wildfires in 2015, 2017 and 2020 burned more than 10 million acres each, mostly in the western United States, releasing plumes of smoke that experts say now account for half of the air pollution in western states. Burned area from wildfires is about four times what it was forty years ago, researchers say, and the problem of the polluted air resulting from fires is growing.

Scientists warn that current health policies are not effectively protecting people against smoke inhalation dangers , and a new study published in July underscored how dangerous levels of tiny pollution particles in wildfire smoke travel into households not threatened by the fire itself.

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