When I went to Calcutta a couple of years ago, I could see from the plane window that there was a large patch of brown around a city on the ground. I wondered what the brownness was, and only when we drew closer to the city, I realized the brown was the air! It was smog!
In Calcutta, everything is brown – the trees, the grass, the buildings, and yes, the people too. You go out of the hotel room and when you come back, your clothes have a layer of brown dust on them. My asthma acted up when I went into the city, and if we had that kind of weather in Singapore, all the schools would be closed everyday.
While the Singapore air is far from fresh, it is relative clean. When I went to Bintan recently, I could see a generally haziness over the Singapore city, and that was when I realized that air pollution in Singapore can really become a problem if the government has not taken steps to reduce the volume of traffic inside the city through the ERP gantries.