Friday: On the day of the Olympic opening ceremonies, the Air Pollution Index reading was a moderate 94 (see the “Beijing Air Quality” box on the right side of this page):

Beijing 8.8.08

View of Beijing’s third ring road and CCTV building. Photo taken Aug. 8.

And here’s the same view one week earlier, when the API reading was a 27:

Beijing 8.8.08

View of Beijing’s third ring road and CCTV building. Photo taken Aug. 1.