Delhi's Air Catastrophe
The World Health Organization recently ranked Delhi's air as the most polluted in the world, worse even than Beijing's. The pollution comes from a number of sources: the dusty environment, hoards of cars and trucks, waste burning, coal-fired power plants within the city, and brick kilns on the outskirts. Delhi's air becomes especially nasty in the winter, when there is little wind to push fresh air into the city and a large number of the city's inhabitants resort to burning trash and biomass to stay warm.
In Beijing, air pollution is thought to reduce life expectancy by 5.5 years. In Delhi, where PM2.5 levels (a measure of the smallest, most harmful air pollutants) were 45% higher than Beijing last year, the effect could be much more severe. Making matters worse, there is little public knowledge of or concern about the air quality in Delhi. In Beijing, nearly everyone will wear face masks when the air turns bad. In Delhi, most people aren't even thinking about air pollution, and it is exceedingly rare to see anybody wearing a face mask. This will change, I hope, but for the time being, Delhi's air pollution is a public health catastrophe that is unfolding largely unnoticed by the 20 million people in the region.