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If Diwali came around in July or August, firecrackers would not have caused as much pollution as they do in October or November. The main reason for the Delhi winter smog is the weather. The winds change in such a way they trap pollutants. This is why Diwali firecracker pollution isn't a one-day affair that can be overlooked; at least in Delhi, meteorological conditions make sure the pollutants are trapped in the air for days. In 2016, there was a clear spike in air pollution in the days following Diwali. This year, thanks to the Supreme Court, we'll have data to tell us the link between firecrackers and pollution. Banning the sale of firecrackers in Delhi NCR till 1 November, the Supreme Court said yesterday, "We are of the view that the order suspending the licenses should be given one chance to test itself in order to find out as to whether there would be positive effect of this suspension, particularly during Diwali period." If the SC's ban on sale of firecrackers is strictly implemented across Delhi and NCR, it will help us compare the pollution figures around Diwali in 2015 and 2016. In both years, Diwali and the days after saw a significant spike. And this year, Delhi has a lot more pollution meters to gather data. The Supreme Court's experiment of banning the sale of firecrackers is worth trying because already we have enough data to show that pollution does go up immediately after Diwali. It is possible that by 1 November, we may find that banning firecrackers has not resulted in changing the annual spike in air pollutants. If that happens, we'll be able to conclude that Diwali firecrackers are an insignificant contributor. It may be a hint that the burning of harvest residue by farmers in Punjab, Haryana and western Uttar Pradesh is a greater contributor. The Supreme Court's experiment of banning the sale of firecrackers is worth trying because already we have enough data to show that pollution does go up immediately after Diwali. One study in 2015 found outdoor PM 2.5 particulates increase by as much as 3.5 times. In 2016, people probably didn't burst any more crackers than they did in 2015. But meterological conditions were worse. Slow wind speed meant firecracker pollutants wouldn't disperse easily, leading to smog so strong that visibility dropped to 200 meters. For days the smog wouldn't leave town. It came to be known as the Great Smog of Delhi.

AFP/Getty Images Commuters drive amid heavy smog in New Delhi on October 31, 2016, the day after the Diwali.

NOT WORTH EVEN A DAY Even if Diwali increases air pollution only for a day or two, that's not something Delhi can afford given Delhi's already unbearable pollution levels. Studies have shown the exceedingly high PM 2.5 and 2.10 levels are making people sick, shortening their lives, and could be causing as many as 8 deaths. It is not reasonable to argue that if we are unable to stop farm fires, Diwali firecrackers must be allowed to pollute the air as well. One study found 70% respondents in a resettlement colony in Delhi had respiratory problems after Diwali. PM 2.10 is dangerous because they are particles so small they enter the lung. PM 2.5 is fatal because they are particles that enter the blood from the lungs, a silent killer. The impact of Diwali firecracker on respiratory health, especially that of infants, asthamatics and the elderly, is well documented. Last year, doctors in Gurgaon found respiratory diseases among children tripled after Diwali. This alone should be good enough reason to ban firecrackers. We are not even talking about the large numbers of children who suffer burns from firecracker accidents. NOT MUTUALLY EXCLUSIVE There are those who argue that farm fires weren't the main reason for the November 2016 smog, such as the Met department. "Had farm fires been the reason for the smog, cities between Delhi and Punjab would have also witnessed low visibility conditions, but that was not the case," IGI Met director-in-charge R K Jenamani told The Times of India after Diwali in 2013. Or perhaps the weather in Delhi NCR is particularly conducive to trapping pollutants? The point is, we have a paucity of data and studies on pollution in Delhi and its suburbs. What we do have is often conflicting. There is little doubt that all sources of pollutants must be brought down. Some argue that main cause of winter pollution is not Diwali firecrackers but road dust, forgetting that Diwali firecrackers turn into road dust. Some argue the main cause is vehicular pollution, but the failed odd-even car rationing did not bear this out. During the odd-even experiment when pollution did decrease it was more on account of weather conditions. On poor weather days, the smog was as bad as ever. It is not reasonable to argue that if we are unable to stop farm fires, Diwali firecrackers must be allowed to pollute the air as well. Similarly, farmers could argue why they are being punished when Diwali firecrackers are allowed.

Hindustan Times via Getty Images A top view of heavy air pollution on the day after Diwali in 2016.