The Atlantic Cities: The air quality in Beijing has grown so bad that it's begun to produce its own catch-22s. All that smog is starting to keep tourists away, but tourism is just the kind of less energy-intensive industry that China needs to develop. The city is hoping to ramp up its public bike-share system, in an effort to shift a majority of trips through the city center onto public transportation. But who would want to ride a bike in this atmosphere? At least one perverse consequence could be helping. The pollution...