Nasa images show crop burning surged before toxic smog hit Delhi-NCR

Punjab Chief Minister Amarinder Singh on Thursday wrote to Prime Minister Modi to intervene to resolve the air pollution crisis that is gripping north India. Crop burning in the states of Punjab, Haryana and Uttar Pradesh is believed to be fuelling growing pollution in the region.

Singh reiterated his request from July asking the PM to bring chief ministers from the affected states and the Union Minister for Agriculture and Environment ministry to the table so a joint solution could be found.

The data from NASA that captured this trend shows that crop burning intensified on October 27, 29 and 31, and was mostly concentrated in Punjab.

A dramatic rise in crop burning in Punjab, Haryana, and Uttar Pradesh has pushed the air quality level in the Indo-Gangetic belt to dangerously high levels this week, experts said on Thursday, putting millions of people at risk and forcing authorities to close schools till Sunday in Delhi.

The apex green court, NGT banned crop burning in 2015 but efforts to check crop burning by fining farmers and to provide some compensation for not burning have failed to make a difference.  The Punjab CM suggested that it was essentially a scientific and economic problem that could not be tackled through other means.

Burning crop residue in paddy fields is a cost-effective way of clearing large farms in a short period of time that is available to farmers to prepare for the next sowing season. Farmer groups have argued that they have no better alternative to burning the crop remnants.

Delhi’s air quality index (AQI), which measures the concentration of pollutants in the air, on Thursday morning was 465 indicating severe levels of pollution. Smog-like conditions continued and low visibility disrupted train schedules with 41 trains running late.

Agricultural stubble running into millions of tonnes is burnt by farmers in northern India every October, before the onset of winter. An estimated 35 million tonnes are set afire in Punjab and Haryana alone to make room for the winter crop.

NASA MODIS data analysed by SN Tripathi and team/ IIT Kanpur.

“It takes about three to four days for the particulate matter to reach a city like Delhi from Punjab,” Sachchida Nand Tripathi, a professor at Indian Institute of Technology, Kanpur, said.

Tripathi, whose team helped collate the NASA data, indicated that the recent surge in crop burning was to blame for the rise in particulate matter pollution in Delhi and the NCR and in surrounding cities.

Particulate matters are tiny fragments produced by fossil fuel combustion and other industrial processes that can lodge deep into the lungs. Prolonged exposure to these particles can cause respiratory and heart diseases.

Particulate matter acts as a nucleus for the condensation of water vapour in the air forming a dense mass known as fog. When mixed with other pollutants, especially sulphur oxides, it takes the form of the more dangerous smog.

According to Tripathi, the particulate matter gets trapped in this belt because of the Himalayan range bordering the plains in the north which acts as a barrier preventing the particulate pollution from being flushed out of the region.

“Northwesterly winds carry smoke and fog from these areas to the Delhi-NCR (National Capital Region),” Mahesh Palawat at Skymet Weather Forecasting, a private agency, said.

The National Green Tribunal banned the burning of crop residue in Rajasthan, Uttar Pradesh, Haryana and Punjab, recognising that they contribute to poor air quality in Delhi and the NCR in 2015 but implementing the order has turned out to be a difficult task.

There has been vigorous pushback from farmers, who find themselves without a viable alternative to get rid of the crop residue from the Kharif season. It is important for them to clear their fields quickly to be able to sow crops for the next season.

The Punjab CM also urged the PM consider adding a bonus of Rs.100/ quintal to the Minimum Support Price (MSP) for wheat and paddy, as an incentive for farmers not to burn the crop residue.

However, there was a steep drop in the crop fires on November 7 as farmers get ready to sow for the Rabi season.

This drop combined with favourable weather conditions, like the surface level winds picking up, will lead to an improvement in air quality after November 10, according to the India Meteorological Department.

First Published: Nov 09, 2017 10:30 IST