Delhi pollution

Stringent measures under the Supreme Court-mandated graded response action plan (GRAP) to control pollution were enforced for the first time since October 17. They will run till March 15 next year.

A range of additional steps such as mechanised sweeping of roads and a crackdown on the burning of garbage were carried out through the year to reduce street dust and smoke that leads to smog.

“The duration and frequency of smog episodes have come down to some extent. But pollution levels are still very high. More sustained and aggressive action is needed to bend the pollution graph,” said Anumita Roychoudhury, executive director (research and advocacy) at the Centre for Science and Environment.

The Supreme Court’s ban on firecrackers during Diwali also had an impact. A report by SAFAR, an agency under the ministry of earth sciences, had stated that the level of emission from fireworks fell around 40% during the festival this year, compared to 2016.

But some experts pointed out that it would be too early to conclude that the steps were showing results.

“We can only say air quality has improved when we monitor pollution data over a period of at least five to 10 years. Secondly, a simple AQI data doesn’t give a fair idea of the level of pollutants. We need to monitor each pollutant over a period before coming to a conclusion,” said SN Tripathi, coordinator at the Centre for Environmental Science & Engineering in IIT Kanpur.

Tripathi also warned that the authorities should not be complacent just because there were some signs of improvement.