Cloud seeding in Delhi: How it works as city awaits first artificial rain on October 29 amid severe AQI

Delhi AQI: Delhi Chief Minister Rekha Gupta on Thursday said that the national capital could receive its first artificial rain on October 29 as cloud seeding preparations have been completed.

The announcement came on the back of rising calls to induce artificial rains as Delhi AQI remains toxic after Diwali.

In a post on X, Gupta said that the weather department has indicated the presence of clouds between October 28 and October 30.

“Preparations have been completed for the first time in Delhi to induce artificial rain through cloud seeding. Today, experts have successfully tested it in the Burari area. The weather department has indicated the possibility of cloud presence on October 28, 29, and 30. If conditions remain favorable, Delhi will experience its first artificial rain on October 29,” she said.

Delhi AQI: How is cloud seeding done?

Cloud seeding is done by scientists who inject silver iodide, potassium iodide, dry ice (solid carbon dioxide), liquid propane or salts into clouds in order to mirror ice nuclei. This is done with an aircraft, which injects the salts into the cloud.

The practice of injecting clouds with silver iodide particles makes sure that even those with naturally occurring ice nuclei are loaded with enough of these particles leading to rains.

Injecting the particles makes clouds more capable of creating ice crystals, that gives rise to precipitation. Depending upon the temperature, these crystals fall as snow flake or melt to lead to rains.

The amount of rains generated from cloud seeding depends on the number of ice nuclei inside the cloud and the amount of water available nearby to grow around it.

What is cloud seeding?

Cloud seeding is a weather modification method to improve a cloud's efficiency to produce rain or snow by introducing small ice nuclei into certain types of subfreezing clouds.

Cloud seeding is done at water-starved areas to bring artificial rains. They are also used to disperse fog and smog blankets in some areas.

Delhi cloud seeding trial done

Delhi Environment Minister Manjinder Singh Sirsa announced on Thursday that the first trial of cloud seeding in Delhi was done by IIT Kanpur on the day with a flight.

“Today, a trial seeding flight was done from IIT Kanpur to Delhi via Meerut, Khekra, Burari, Sadakpur, Bhojpur, Aligarh, and back to IIT Kanpur, in which cloud seeding flares were fired between Khekra and Burari and over the Badli area using pyro techniques,” he wrote om X.

“This flight was the proving flight for checking the capabilities for cloud seeding, the readiness and endurance of the aircraft, the capability assessment of the cloud seeding fitments and flares, and coordination among all involved agencies,” the minister added.

Delhi AQI has remained in the ‘very poor’ category for four consecutive day post Diwali, with the air quality index hitting the ‘severe’ mark in many areas. Delhi was the fifth most-polluted city in the country on Thursday, with the post Diwali AQI being the worst in four years.