Face mask-clad Singaporeans enduring record-breaking smog got some more bad news from their government on Thursday: The pollution may last awhile.
The choking smog that blanketed the city-state earlier this week, generated by burning clear-cutting fires in Indonesia, has gone well beyond the "hazardous" level on the Pollutant Standards Index, hitting 371 on Wednesday before coming back down to about 250. The previous record was 226, reached in 1997.
Cities like Houston are dotted with air-sniffing monitors that measure levels of benzene and other potentially unhealthy air pollutants. But those monitors can't answer the question we care about most: Is the air safe?
That's because there's no simple relationship between toxic air pollutants and health risks. Researchers at the University of North Carolina in Chapel Hill are trying to get a leg up on that problem. They are building an instrument that uses human lung cells to measure health hazards in the air more directly.
If you stand in front of Almena and Sidney Poray's house in Baton Rouge, La., and look straight down the street, past the other houses and the shade trees, you see more than a dozen plumes of exhaust in various hues of gray and white.
"That's something you see every day, the same thing if not more," says Almena Poray. "Sometimes it's a darker gray; sometimes it's a black smoke coming out."
Denise Mauzerall arrived in Beijing this year at a time that was both horrifying and illuminating. The capital was facing some of its worst pollution in recent memory, and Mauzerall, a Princeton environmental engineering professor, was passing through on her way to a university forum on the future of cities.
"I took the fast train from Beijing to Shanghai, and looking out the window for large sections of that trip, you couldn't see more than 20 feet," Mauzerall recalled.
To Mauzerall, the lesson was surprising and inescapable.