Smog descends upon Beijing. Winter is fast descending upon China, and with it, thick clouds of smog. Last week, officials shut down schools and major roads in the northeast city of Harbin after air pollution there reached dangerously high levels. The smog has since subsided in Harbin, but the outbreak has revived longstanding debates across China, where rapid economic growth and a lingering dependence on coal have combined to deteriorate air quality at alarming rates.