…from its toxic air?
In A River Runs Again, I explored the devastating effects of cook fires on human and climatic health, but they are just one part of what is causing New Delhi to claim the worst air quality of any major city in the world. Since January, I’ve been researching what it is that makes Delhi’s air so toxic and what steps the city is undertaking to try to improve it. Here’s the start of the piece just published in Nature:
On winter nights, New Delhi burns with innumerable fires. Flames flicker along pavements and street corners, where the destitute huddle to stay warm and cook their suppers, while night watchmen stand guard next to their own small blazes outside private homes. The rising plumes of smoke mingle with exhaust and dust stirred up by overloaded trucks that rumble down roads blanketed in fog. The mixture melds into a nearly opaque substance that leaves a metallic taste on the tongue. Overhead, there is not a single star to be seen.
As for action, encouraging news came a couple weeks ago, with the announcement of a plan to spend almost $3 billion to reduce traffic congestion in New Delhi, although it still needs to be approved and some of the measures are ones that have failed in the past, such as Bus Rapid Transit systems. But a move for more buses, and more pedestrian crossways, and to actually make parking on a footpath an offense, is an excellent start. Increased attention to the issue is a hopeful indicator of more action to come.
If you want to know more, nonprofits such as the Centre for Science and the Environment and Care For Air both are work to inform the public about the city’s air quality, UrbanEmissions brings together concise graphics and scientific information to help understand a complicated issue, and the Air Quality in Delhi Facebook group connects concerned citizens.
I also wrote a couple of pieces specifically about the odd-even traffic reduction plan that was underway when I was in Delhi in January. “New Delhi car ban yields trove of pollution data” was in Nature and the piece with the (mildly overblown!) title “Amazing Things Happened When New Delhi Halved the Number of Cars on the Road” ran in Vice News.
Measuring air quality is incredibly tricky business. The 122 micrograms per cubic metre (μg m−3) of PM 2.5 that is the latest WHO figure is the ANNUAL average, while the comprehensive report from IIT-Kanpur that is used for the Nature graphic, and shows figures in the 300-375 range, are DAILY averages. There are many many ways to assess air quality — from analyzing hand-held air filters to using satellite data — and the different methodologies lead to varying numbers. There are apples and there are oranges. The same goes for figuring out what it is that’s causing the air pollution in the first place. The good news is that there is a definitive upturn in the amount of research and attention being paid to air pollution in Delhi and around the world, just as its recognition as a major human health risk is increasingly being recognized. For the sake of journalists, researchers, policy makers, citizens, and the planet, I hope that more research leads to more uniformity in methodology, leading to more knowledge about how to combat this pervasive pollutant.