And here it is on Jan. 14:
It doesn't sound pretty:
The top image shows extensive haze, low clouds and fog over the region. The brightest areas tend to be clouds or fog, which have a tinge of gray or yellow from the air pollution. Other cloud-free areas have a pall of gray and brown smog that mostly blots out the cities below.
At the time that the Jan. 14 image was taken, ground-based sensors at the U.S. Embassy in Beijing reportedly found levels of the smallest, most dangerous types of particulate matter, known as PM 2.5, at 291 micrograms per cubic meter of air. According to World Health Organization guidelines, any air with more than 25 micrograms of PM 2.5 per cubic meter is considered unsafe.
The PM 2.5 particles, which come from burning fossil fuels and biomass, are especially deadly because they can enter the passages of the lungs. Over time, they can worsen medical conditions such as asthma or heart disease.
But immediate relief is unlikely, and air pollution issues of this scale take decades to alleviate.
"If there is any consolation to what Beijing had to endure," wrote the Economist's China blog, "It is that it should lend urgency to the public outcry, and help speed things in the right direction."
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