Wildfire smoke brings worst air quality to Portland, Seattle

SEATTLE (AP) — Smoke pollution from wildfires raging in California and across the Pacific Northwest worsened in San Francisco, Seattle and Portland, Oregon, on Friday, giving those cities and others in the the region some of the world’s worst air quality.

Public health officials warned residents to keep indoors with the windows shut, to set air conditioners to run on recirculated air instead of fresh, and to use air purifiers if they had them. Meanwhile, they wrestled with whether to open “smoke shelters” for homeless people or others lacking access to clean air amid the COVID-19 pandemic and concerns about herding people indoors.

“The same population that is most vulnerable to the virus is also most vulnerable to the smoke,” Seattle Mayor Jenny Durkan noted during a news conference.

The sky turned a hazy, grayish white across the Northwest as winds that had previously pushed much of the smoke offshore shifted, bringing unhealthy levels of near-microscopic dust, soot and ash particles to Portland, Seattle, and Vancouver, British Columbia. San Francisco also continued to suffer from smoke pollution; those four cities topped the list of major cities with the worst air quality Friday, according to IQAir.com, which tracks air quality around the world.

The smoke was expected to linger through the weekend, another reminder of the vast and severe effects of climate change. The particles are small enough that they can penetrate deep into the lungs, and health effects can include chest pain, arrhythmia and bronchitis. Those with preexisting conditions such as heart and lung disease or asthma are especially at risk.

Seattle ordered parks, beaches and boat ramps closed through one of the last hot weekends of the summer to discourage outdoor recreation, and officials were opening a clean air shelter Friday...