So I can't speak for commuter traffic in other cities (other than my brief time in GZ), but in Beijing, morning and evening rush hour subway rides have become unbearably crowded in the past month ...

So I finally bit the bullet and bought a face mask yesterday...yeah, 2 days after the worst recorded air pollution the city's ever seen. What can I say, I didn't want to leave the house this ...

Only a month or so ago did I discover the US embassy's Air Quality Index (which, to my understanding basically indicates how fast Beijing's air is going to kill me) and it's been freaking me out ...