Do we know what pollutes Delhi/NCR air and the surrounding region? The answer is a very highly qualified ‘yes’. We know enough to inform action now, even while it is important to keep filling in the knowledge gaps. While there are multiple pollutants, in this article we focus on PM 2.5 or very small particles that experts agree are a major health hazard in India.
In examining sources, one fact stands out: There are at least four discrete sectors that each substantially contribute to Delhi’s pollution (see figure): industry; transport; biomass and waste burning; and dust. Delhi’s air problem is so hard to solve in part because it is not a single problem; it is a 4 X 25% (+/-10%) problem, with at least four implications.
Sector-based contribution to PM2.5 – Gfx (Delhi Metro pg 15; Date: December 21, 2018) – Embed code inline script. Read More