This is the view from the office where I work. You can easily see the difference between a clear day and polluted day.
In my estimation, there are definitely more clear days than polluted days, but the levels of pollution do have quite the range. These pictures merely illustrate the extremes. Sometimes the reality is removed from what it looks like out the window, so I like to stay updated via http://twitter.com/beijingair#
In closing, the Beijing air is like the little girl who had a little curl right on the middle of her forehead. When she was good, she was very good, but when she was bad, she was horrid.
