New Delhi: After deteriorating to the season’s worst Sunday, prompting the Delhi government to issue a health advisory asking people to stay indoors, the air quality in the national capital improved several notches Tuesday. The Air Quality Index (AQI) was recorded at 381 in the morning — an improvement from ‘severe plus’ to ‘very poor’.
In what can be called a coincidence, the AQI sees this dip just a day after the Arvind Kejriwal government implemented odd-even traffic rule in the capital, aiming to bring pollution levels down. The government’s pollution monitoring system, SAFAR, had already predicted that the AQI levels will improve this week due to favourable weather conditions.
The odd-even scheme, which allows cars with even registration numbers to ply on roads on even dates and vice versa, started Monday.
According to experts, however, the odd-even rule would be able to keep only around 20 per cent vehicles off roads, and that’s not adequate to check pollution down.
“Delhi has over 30 lakh car users. With all women riders, two-wheelers etc exempted from the rule, on a given day odd-even removes less than 20 per cent of the vehicles off the road,” said Chandra Bhushan, former deputy director of Centre for Science and Environment who has worked in the field of environment research for over 25 years.
“This is not enough to make a significant difference to the severe levels of pollution that the city witnessed (in the last few days),” Bhushan told ThePrint.
At 650, the AQI in Delhi had reached alarming levels Sunday, with heavy smog engulfing the region. The resultant low visibility also severely affected flight operations and train movements.
The Supreme Court-appointed Environment Pollution (Prevention and Control) Authority had already declared a ‘public health emergency’ last week after the pollution levels in the region entered the “severe plus” category.
The AQI ‘improved’ to 588 Monday but continued to remain in the ‘severe’ category. The visibility had improved by afternoon, though.
On Tuesday, the AQI dropped further to 381.
Soon after the AQI levels started dropping Monday, Twitter users had started pointing out that pollution was down hours after the odd-even scheme was implemented, with Kejriwal retweeting several of these posts. The CM too posted a tweet saying Delhi’s air was clearer Monday and gave some credit for it to the odd-even rule.
ऑड ईवन और अन्य कारणों की वजह से आज दिल्ली की हवा कल के मुक़ाबले साफ रही
हमें मिलकर कोशिश करनी है कि आनेवाले दिनों में कम से कम दिल्ली का अपना प्रदूषण काबू में रहे। https://t.co/NDXlttDnZM
— Arvind Kejriwal (@ArvindKejriwal) November 4, 2019
PM 2.5 & PM 10 levels in #Delhi before & after #OdDEven pic.twitter.com/2mqcMQYD3x
— NBT Dilli (@NBTDilli) November 4, 2019
आसमान और हवा काफी हद तक साफ है ..कई दिनों बाद सांस में सांस आई है ..अगर इसमें थोड़ा भी योगदान ODD -EVEN का है तो @ArvindKejriwal की सरकार को बधाई ..सियासत के लिए ऐसी कोशिशों को खारिज करने की बजाय एक जुट होकर इस समस्या पर सोचने की ज़रूरत है #DelhiNCRPollution pic.twitter.com/pf7piFx4F1
— Ajit Anjum (@ajitanjum) November 5, 2019
Also read: Hold government accountable for Delhi air pollution but also punish selfish behaviour
Change in wind direction by November 8
The System of Air Quality and Weather Forecasting And Research (SAFAR) had predicted Sunday that pollutants in the air would partially disperse by evening due to favourable weather conditions.
According to the agency’s report, Sunday’s extreme pollution was a result of the light showers and calm wind conditions that caused an increase in humidity.
Due to cloudy skies and insufficient sunlight, the report said, a ‘unique condition’ — foggy period like what is experienced in December and January — was created. This caused a higher- than-usual accumulation of pollutants.
But such rapid accumulation of pollutants don’t usually last long, and a retreating trend in hourly levels of PM2.5 started after 5 pm Sunday.
The agency had also predicted a significant improvement by the afternoon of November 4, due to favourable wind conditions.
According to the SAFAR report, scattered rainfall and change in wind direction are expected in the Delhi region by November 8, and this is likely to positively influence the AQI.
Odd-even rule wasn’t effective in past
While vehicular pollution is a significant contributor to Delhi’s air pollution problem, reducing a certain number of cars is not expected to drastically bring down pollution levels in the city.
Studies have shown the odd-even scheme to be ineffective in the past.
A 2018 study said the odd-even rule had been counter-productive, with vehicular pollution levels even going up in the days during which the scheme was in effect.
It also showed that used cars sales went up, as people began to keep more than one car to circumvent the problem.
Hearing a matter concerning pollution in the National Capital Region, the Supreme Court Monday went on to ask the Delhi government as to what it was achieving from the odd-even scheme.
A bench comprising Justice Arun Mishra and Justice Deepak Gupta said two-wheelers, three-wheelers and taxis would ply more during the odd-even scheme whereas pollution emissions from cars, especially petrol-run, was less as compared to taxis and auto rickshaws.
Also read: How Delhi’s air crisis can be resolved by curbing paddy cultivation in Punjab, Haryana
Well it is easy to comment about the effectiveness or non effectiveness of the Odd-even. But if we are going to criticize every step of the state government what is it that we will achieve. One thing to be kept in mind is that there is no perfect time to do something. That perfect time will never come. it is good to remove the tinted glasses and throw out the political cap and be practical and talk sense. It is each individual’s responsibility to ensure that the factors that are responsible for pollution are minimized. Action on the ground is needed. All talk and no action serves no purpose.