Delhi’s overall air quality was in the ‘very poor’ category, on November 20, 2018, while in some areas of the city it was ‘severe’, with authorities saying they may induce artificial rain by cloud seeding, to wash away pollutants in the air, although no exact date has been set for it. Authorities said the ‘very poor’ air quality was due to low wind speed, which is not favourable for the dispersion of pollutants.
According to the Central Pollution Control Board (CPCB) data, the overall air quality in the city was recorded at 372, which falls in the ‘very poor’ category. Ashok Vihar, Anand Vihar, Bawana, Mundaka, Rohini, Sonia Vihar and Wazirpur, all recorded ‘severe’ air quality, while 21 areas recorded ‘very poor’ air quality, it said. At 396, the overall air quality of Ghaziabad was the worst in the National Capital Region (NCR), just points below the ‘severe’ category. Gurugram, Faridabad, Noida and Greater Noida too recorded ‘very poor’ overall air quality.
On November 20, the PM2.5 (particles in the air with a diameter of less than 2.5 micrometres) level was recorded at 220, while the PM10 level was recorded at 369, the CPCB data said. According to the centre-run System of Air Quality and Weather Forecasting (SAFAR), air quality in the national capital is expected to remain in the ‘very poor’ category for the next two to three days. “At present, the wind speed is unfavourable for dispersion but it may increase slightly to favour dispersion. Humidity is still high, which is unfavourable. Fire counts from stubble burning declined and will have marginal impact,” the SAFAR said in a report.
In the wake of rising air pollution in the city, authorities might induce artificial rain by cloud seeding, to wash away the pollutants, although no exact date has been set for it. Cloud seeding for artificial rain would be done, once the meteorological conditions are stable, a senior official said. He said the plan is to induce rainfall this week but if the meteorological conditions are not found suitable, then, it would be done next week. However, a senior Environment Ministry official said, “No exact date has been set for this. This is a possible solution. We will give more details about it.”
A senior official said seeing the meteorological conditions, there is no possibility of inducing artificial rain. “Even for artificial rain, we need clouds and currently the meteorological conditions are not favourable for inducing an artificial rain,” he said.
The official also said the method of artificial rain is used only in ‘severe plus’ emergency situation.
Cloud seeding is the process of combining different kinds of chemical agents, including silver iodide, dry ice and even table salt, in clouds, to thicken them and increase the chance of rainfall. In 2016, the government tried to explore the possibility of cloud seeding for artificial rain but the plan never worked out.
Meanwhile, concerned about poor air quality in Delhi, a group of college students have come together to monitor the air quality index daily in several locations in the city, including in schools, hospitals, markets, bus stops and government buildings. By this, they hope to raise awareness among people about the health hazards posed by pollution. “It is an attempt to mobilise the community, in the fight to improve air quality,” a statement said. The drive is a joint initiative of Help Delhi Breathe, Haiyya, a grassroots mobilisation organisation and Ambee, a company working on air quality data and analytics.