San Francisco currently ranks among the worst places for air quality as smoke from wildfires in northern California and Oregon descends on the Bay Area.
The city has the seventh most polluted air among regions of the world, behind Lahore in Pakistan and Jakarta in Indonesia, according to IQAir, a monitoring company. While pollution is likely to play a role in San Francisco's poor air quality, tracking data shows it has gone from being deemed "good" on Monday to nine times the annual pollutant guideline set by the World Health Organization as of Tuesday.
Overall, the West Coast city of more than 815,000 people has an air quality index (AQI) rating of 123, the government's AirNow monitoring platform says, meaning it is likely unhealthy for sensitive individuals. IQAir puts its AQI at 107—above Kampala in Uganda and Johannesburg, South Africa.
The National Weather Service (NWS) station in San Francisco attributed the smoky conditions to the Anvil Fire in southwest Oregon—which currently ranges across 9,023 acres—as well as smaller wildfires in northwestern California, the smoke from which was being carried on northerly winds.
The warnings come after vast swathes of the north and eastern U.S. were smothered in smoky fog that descended from massive wildfires in Canada earlier in the summer. The nation is on track to have its worst wildfire season on record, which experts have said was facilitated by hot, dry conditions caused by climate change.
The NWS said on Tuesday evening that "more wildfire smoke and haze" is forecast to arrive overnight and into Wednesday. AirNow expects San Francisco's air quality to remain moderately poor through to Saturday.
"Smoke will continue to drift into portions of the Bay Area through Thursday," Anthony Edwards, a meteorologist for the San Francisco Chronicle, predicted. "The highest concentrations of smoke will likely remain in the North Bay, but parts of the Peninsula and East Bay will experience periods of haze in the next few days."
Maps produced by the federal government show San Francisco and San Jose to be among the worst-affected areas of California, with unhealthy air quality also recorded in Santa Cruz, Salinas and Monterey.
On Tuesday evening, the San Francisco Department of Emergency Management moved its air quality rating for the city to "red," suggesting it was now at "unhealthy" levels.
"Active youth, adults, and people with respiratory diseases should avoid prolonged outdoor exertion," it advised residents. "Everyone else, especially children, should limit outdoor exertion."
On Wednesday, the agency announced a resilience program that will provide air filtration and conditioning to 90 community organizations "that serve populations vulnerable to heat and poor air," including Self-Help for the Elderly and Boys & Girls Clubs of San Francisco facilities, it confirmed to Newsweek.
It added that nearly 200 locations had applied for the air quality regulating equipment and that it would disburse more "if additional resources are secured."
The San Francisco Fire Department has also noted it had been receiving calls about the smoky air.
The blazes on the West Coast come after a spate of heat wave-induced wildfires that spread across the southwest United States, as well as Europe.
More recently, wildfires riding on dry conditions and spread rapidly by hurricane winds brought death and devastation to the Hawaiian island of Maui.
Update 09/21/23, 3:16 a.m. ET: This article was updated to include further information from the San Francisco Department of Emergency Management.
Uncommon Knowledge
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Newsweek is committed to challenging conventional wisdom and finding connections in the search for common ground.
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Aleks Phillips is a Newsweek U.S. News Reporter based in London. His focus is on U.S. politics and the environment. ... Read more
