Delhi’s air quality improved to the “moderate” category on Thursday morning due to strong winds and isolated rain a day after it deteriorated to the “poor” zone for the first time in nearly three months. A 24-hour average air quality index (AQI) of 121 (moderate) was recorded at 9 am on Thursday, a sharp drop from 235 (poor) at 4 pm on Wednesday. The average AQI was 197 (moderate) on Tuesday.
Scattered light rain across the city until Saturday was expected to keep AQI in “moderate” category. Winds of 20-30 km per hour are also expected.
An AQI between 0-50 is classified as “good”, between 51 and 100 “satisfactory”, between 101 and 200 “moderate”, between 201 and 300 “poor”, between 301 and 400 “very poor”, and over 400 “severe”.
On Wednesday, the AQI touched the “poor” category in September for the first time in nearly six years. The last time this happened was on September 29, 2018, with the AQI touching 219.
The Commission for Air Quality Management (CAQM) in the National Capital Region on Wednesday said it would not invoke Stage 1 or the “poor” category measures under the Graded Response Action Plan (GRAP), citing the likely improvement in air quality due to the forecast of rain.
A combination of showers and strong winds has a washout effect that helps settle pollutants and dissipate gases to keep air quality in check.
{{/usCountry}}A combination of showers and strong winds has a washout effect that helps settle pollutants and dissipate gases to keep air quality in check.
{{/usCountry}}CAQM on Wednesday said Delhi’s average AQI improved to 232 at 5 pm and was further expected to improve. It cited the forecast and said it also indicates light rain showers in Delhi on Wednesday and in the coming few days, thus leading to further improvement in the overall AQI in the “moderate” category. “...will keep a close eye on the situation for further decisions,” said CAQM in a statement following an emergency meeting.
Stage 1 of GRAP can be implemented any time AQI crosses 200 and has a set of 24 preventive measures including increased mechanised sweeping and sprinkling on roads, shutting down construction and demolition sites with an area over 500 square metres that are not registered with the government, increased deployment of traffic police at congestion points and drives against overage vehicles.
On Wednesday, the Delhi government unveiled a 21-point Winter Action Plan to combat air pollution this winter, which includes utilisation of drones at pollution hotspots to identify sources of pollution, the formation of a six-member task force, the distribution of green awards to recognise people’s contribution against air pollution and artificial rain as an emergency measure.