Spike in Delhi pollution as winter spiral begins
The air quality index (AQI) slumped from an uncharacteristically clean 271 on Wednesday to 354 on Thursday, according to the 4pm bulletins released on both days by the Central Pollution Control Board.
The air quality in Delhi plummeted to its worst levels since January as smoke from smouldering paddy fields in Punjab and Haryana drifted in, marking the beginning of what has been an annual environmental blight that is only predicted to worsen, with more farm fires likely and unhelpful meteorological conditions predicted to persist.
The air quality index (AQI) slumped from an uncharacteristically clean 271 on Wednesday to 354 on Thursday, according to the 4pm bulletins released on both days by the Central Pollution Control Board.
An AQI above 300 is considered “very poor” – the second worst band on the AQI scale. At least two regions in the city, Anand Vihar and Ashok Vihar, had an AQI above 400, which lies in the worst “severe” band.
“Wind speeds have dropped significantly from October 26 onwards and we are seeing calm wind conditions at night time. Delhi saw calm wind conditions for nearly seven hours between 4.30am to 11.30am on Thursday, with this spell playing a significant role in accumulation of pollutants,” said RK Jenamani, scientist at IMD.
This was Delhi’s highest AQI in over 10 months; on January 21, it was 365.
Forecasts show similar calm conditions are expected to prevail until the end of the month now, largely keeping Delhi’s air quality in the “very poor” category.
According to officials in Punjab, roughly about 8,100 farm fires have been recorded till now – 20% higher than what was recorded until October 27 last year, indicating a failure on the part of the state government to stem the tide – and a sharper spike is expected in the coming weeks since farmers in the south Malwa belt of the state, where farm fires are widespread, are only now beginning to clear their fields.
Major rice-producing districts such Bathinda, Moga, Mansa, Muktsar and Faridkot have recorded only 20-40% harvesting, said an official of the state agriculture department on Thursday.
In the last four of the five years, the number of fires in south Malwa accounted for close to 50% of the fires recorded in Punjab.
Behind the deterioration in Delhi’s air quality was the perfect storm of conditions: the direction of winds changed to northwesterly that fed in a stream of smoke from fires, the number of fires itself spiked in recent days, local winds weakened that help blow away dust and tailpipe gases died down, and the temperature dipped, creating an “inversion” effect that causes pollutants to settle closer to the ground, instead of being dispersed higher into the sky.
Anumita Roychowdhury, executive director, research and advocacy at the Centre for Science and Environment (CSE) said when the farm fire impact begins to be felt more strongly, “the AQI could considerably worsen. Till now, Delhi was seeing good wind speed, which was controlling the pollution levels. As soon as winds become calm, local emissions are enough to cause the AQI to reach ‘very poor’,” she said.
A Commission for Air Quality Management (CAQM) official said while forecasts were showing “very poor” air till October 30, the next six days show AQI hovering between “poor” and “very poor”. “We will hold a review meeting if the forecasts show severe air. Based on that, a discussion can be held on whether the next stage of the Graded Response Action Plan (Grap) needs to be implemented or not.
Apart from Punjab, farm fires were reported from other neighbouring states too. Satellite data from the Consortium for Research on Agroecosystem Monitoring and Modelling from Space (CREAMS) at the Indian Agricultural Research Institute (IARI) showed Punjab, Haryana and Uttar Pradesh recorded a combined fire count of 1,218 fires on Thursday, a marginal dip from Wednesday’s figure of 1,384 fires.
VK Sehgal, professor & principal scientist at IARI said farm fire figures normally touch around 2,000 by the end of October, with the peak coming in the first two weeks of November. “Based on the current trajectory, it is expected that the peak could come by the first week of November. During the peak, farm fire counts can touch around 5,000 to 6,000 fires in a single day,” he said.
After paddy is cultivated through mechanised harvesters, stubble of 10-20cm is left behind in the fields. These straws make it difficult for farmers to sow the seed for the next crop. The easiest, cheapest and the quickest way is to set the field alight, reducing the stubble to ash.
This practice has persisted for close to a decade now despite the annual hand-wringing over the air quality crisis that it triggers in India’s national capital and adjoining regions, putting the health of millions at risk. The Aam Aadmi Party (AAP) government has in previous years blamed Punjab for Delhi’s pollution crisis. The party is now in power in both states.
Unions representing farmers said more fires will take place this year because it will otherwise be difficult to clear the fields for the next crop. “A delay in sowing paddy and untimely rains delayed harvesting paddy crop. It further reduced the time of completing paddy harvesting and wheat sowing, and farmers are left with no choice other than burning stubble. If wheat is sown after November 10, it would have a direct impact in yield that farmers cannot afford,” said Sanyukt Samaj Morcha leader and farmer rights activist Prem Singh Bhangu.
Over the last two years, the total number of farm fires spotted in the state are over 70,000.
Kuldeep Singh of Pangota village, who defied Punjab government guidelines and burnt the paddy residue, said, “Instead of giving a concrete solution for managing stubble, governments make policies in drawing rooms, which are not suitable for farmers. They ask us to use a bailer, but no one is here to purchase paddy straw bales. The agriculture department asked me to use in-situ handling, but my tractor does not have enough horsepower to pull such heavy machinery. Besides that, I don’t have such a deep pocket to burn extra diesel to handle straw. The only solution is that the government sends machinery to make straw bales and collect it, or set up a power plant where we can sell it.”
Meanwhile, the Capital braces for another winter choke.