Come winter, Delhi is gagging on smog yet again. According to estimates, if you are in Delhi right now, you are passive-smoking the equivalent of 20 cigarettes with the Air Quality Index reading 474. How did it come to this in Delhi and the National Capital Region (NCR)? What is the government doing about it? Is there a way to avoid these apocalyptic scenes in the future? Here's a look.
How is air pollution measured?
The rate of pollutants in the air is measured through an Air Quality Index (AQI). AQI gets its reading from air quality sensors and these readings are categorised into ranges which give people an understanding of the quality of air in their area. Essentially, a higher AQI implies a high concentration of pollutants in the air. India's National Air Quality Index was actually a product of the Swachch Bharat Abhiyaan and was launched in 2014. It measures eight pollutants in the air and corresponding AQI values are assigned to five categories between the range of 0-50 (good) to 401-500 (severe). In Delhi and the NCR this season, the AQI in some areas has crossed 700. As per the index, at 401-500 AQI healthy people are also under threat of developing respiratory issues and it is likely to have severe consequences for those already suffering from heart and lung complications.
Factors responsible for air pollution in Delhi this season
With the Monsoon having passed, as winter sets in in Delhi, the cold dense air becomes a vessel for various pollutants to stay trapped in the atmosphere. The generators of these pollutants range from vehicular emissions to industrial smoke and the discharge from firecrackers burst during Diwali. Significantly, the shift in the sowing season of the Kharif season from June to July, with the harvest in October, leaves farmers with little time to clear the stubble before they start sowing the Rabi crop in November. Stubble burning in neighbouring states of Haryana and Punjab continues to contribute a major percentage of the pollutants in Delhi and the NCR at 34%. Haryana has seen a 30% drop in stubble burning this year, thanks to more awareness among farmers on pollution, and the use of balers to compress the left-over paddy. Union Minister for Environment, Bhupendra Yadav also claimed that the use of the pusa biodecomposer which turns stubble into manure has been successfully deployed in Haryana and Uttar Pradesh, thereby reducing stubble burning further. On the other hand, the AAP government in Punjab insisted on using this decomposer only in 5000 out of the 75 lakh acres of land under paddy cultivation.
What steps have governments taken to bring these factors under control?
Toxic air in the winter has become a norm in Delhi for some time now. Accordingly, governments have been taking preventive measures as well to bring pollution under control. The measures to prevent stubble burning are an example. The Delhi government also imposed a strict ban on firecrackers this year, with offenders attracting up to six months in jail and a fine. However, that ban was, in part, ineffective. Last week, the government also launched a campaign encouraging commuters to switch their vehicles off at traffic signals. Construction work has been halted, there's a ban on burning waste and a hike in parking fees to discourage people from using private transport. Entry of trucks has been banned in Delhi, and the odd-even policy for cars is also back. People have been advised to stay indoors, primary schools will be closed from tomorrow and work from home has been allotted to 50% of government employees.
What impact has the AQI had on the health of the people?
While an AQI worse than 500 is leaving healthy people with burning eyes, cough and headaches, it can spell disaster for people already battling with lung and heart disease. Old people and young children are also at extreme risk. Hospitals are reporting an uptick in cases of nose, throat, ear and chest infections, and also in the number of pneumonia cases. Such a concentration of toxins, if inhaled, can also leave long-term health issues for people of all ages, experts suggest.
When is this expected to let up?
The way the wind blows is actually a huge factor in easing pollution in the NCR. In the last few days, the wind had been blowing in from stubble-burning areas into the NCR, taking the AQI up to the 700-1000 range. From November 5, moderate surface winds are expected to ease out the pollutants and bring the AQI to the 'Very Poor' category. Then again, the season of smog might as well continue well into early January if trends from the last couple of years are anything to go by.
