The U.S. Embassy in Beijing recorded the highest levels of air pollution on Saturday since it began its monitoring system in 2008. The Environmental Protection Agency deems air pollution levels between 301 and 500 to be “hazardous,” meaning people should avoid all outdoor activity. On Saturday night the air-quality monitoring device above the U.S. Embassy in Beijing took a reading of 755, which the embassy’s @BeijingAir Twitter feed called “Beyond Index.” Using the same standards, the air quality index in New York City was found to be 19 at 6 a.m. on Saturday.

Via:

In online conversations, Beijing residents tried to make sense of the latest readings.

“This is a historic record for Beijing,” Zhao Jing, a prominent Internet commentator who uses the pen name Michael Anti, wrote on Twitter. “I’ve closed the doors and windows; the air purifiers are all running automatically at full power.”

Other Beijing residents online described the air as “postapocalyptic,” “terrifying” and “beyond belief.”
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It was unclear exactly what was responsible for the rise in levels of particulate matter, beyond the factors that regularly sully the air here. Factories operating in neighboring Hebei Province ring this city of more than 20 million. The number of cars on Beijing’s streets has been multiplying at an astounding rate. And Beijing sits on a plain flanked by hills and escarpments that can trap pollution on days with little wind. Meanwhile, one person hiking at the Great Wall in the hills at Mutianyu, north of Beijing, took photographs of crisp blue skies there.

In a 2009 State Department cable obtained by WikiLeaks, a Chinese Foreign Ministry official, Wang Shu’ai, told American diplomats to halt the embassy Twitter feed, saying that the data “is not only confusing but also insulting,” and that the embassy data could lead to “social consequences.”

I'm not certain how the destruction of all life on Earth gets filed under "Potential Social Consequences," but clearly this accentuates the need for every able-bodied person to be screaming out for efforts to save the planet to become the primary concern for all governmental leaders and heads of state.