Delhi Celebrated The Cleanest Diwali Since 2014, Says Study
After the Supreme Court called for a ban of sale and purchase and use of firecrackers during the period of the festival of Diwali, the level of emissions from fireworks fell by around 40 per cent as compared to the levels in 2016, as per findings of SAFAR. SAFAR is an air quality and weather forecast and research organisation under the Ministry of Earth Science.
The study concluded that the Diwali period, from October 18-October 22, was the cleanest since 2014. Though the level of particulates did shoot up a day after Diwali, owing to an incredible use of fireworks even after the ban, the dispersion was quicker and air quality attained the pre-Diwali level within three days.
The numbers unveiled
When comparing the current emission levels with that of in 2016, the drop has been significant. The data in the study show a 50 per cent drop on October 19 (Diwali); a 25 per cent drop on October 20, when pollution peaked and a 45 per cent drop on October 21.
The amount of PM 2.5, measured in micrograms per cubic metre (ug/m3), recorded under the study by SAFAR stood at: 136 ug/m3 on October 18, 174 ug/m3 on October 19, 407 ug/m3 on October 20, 203 ug/m3 on October 21 and 139 ug/m3 on October 22. The 24-hour safe standard is 60 ug/m3.
Fewer fireworks, but air quality ‘severe’?
The study shows that less amount of firecrackers were burnt this year when compared to previous years. Still, the air quality turned "severe" for the first time in 2017, a day after Diwali. According to SAFAR project director, Gufran Beig, the reduction in emissions from a particular source and reduction in levels of pollution are not linearly related or directly proportional.
There has been an incredible amount of fireworks that still burned this year, despite the relative reduction, on Diwali night. This led to trapping of smoke in the air and a rapid build-up of pollutants, especially between midnight and 4 am on October 20, aided by a fall in temperature and lowering of mixing height.
"The ban on crackers certainly had an impact. The days that preceded and followed Diwali saw restraint from people. Usually, crackers are set off before and after the actual night of festivities as well. The real impact could be seen on October 20," said Beig.
Not just the firecrackers, there have been other external reasons that have led to the rise in pollution levels in the national capital. One of them was the burning of paddy stubble in Haryana and Punjab. This, according to the study by SAFAR, contributed 10 per cent of the total pollution.
Stubble-burning incidents drop, too
A major cause of air pollution in Delhi this time every year is the burning of paddy stubble in Haryana and Punjab. But, according to the Punjab Pollution Control Board (PPCB), the stubble burning in Punjab has dropped by 30 per cent this year as compared to last year.
The PPCB recently shared these numbers with a Bench headed by National Green Tribunal (NGT) Chairperson Justice Swatanter Kumar. According to PPCB, there were 14,432 cases of burning of crop residue this year as compared to 22,269 cases in 2016.
The NGT had on October 11 directed Punjab to produce the farmers before it after the state claimed to have provided assistance to some of them to encourage them not to burn crop residue.
Steps taken last year
- In October-end 2016, the Delhi government had launched a mobile application, Hawa Badlo (this could be loosely translated into, change the air). The app made the public a partner in dealing with pollution. One version of the app allowed them to share pictures of any dirty site and report it to authorities; and the other would help authorities identify valid complaints and address them, accordingly.
- The government had also taken steps to cut down dust emitting from construction sites. It also announced measures, such as vacuum cleaning and sprinkling of water on arterial roads and prohibition on burning of leaves to make the air cleaner.
- Even after the many measures, according to a report by Associated Press, “By Monday morning (October 21), the city was recording PM 2.5 levels above 900 mcg per cubic metre, more than 90 times higher than the WHO recommendation of no more than 10 mcg per cubic metre.”
With inputs from Housing News