Delhi likely to trial cloud-seeding from Oct 9-11

Delhi plans cloud-seeding trials for artificial rain from October 9-11 to combat pollution, with IIT Kanpur operating the aircraft from Hindon airbase.

New Delhi

Delhi-NCR suffers from heavy pollution in winter due to a combination of meteorological factors, stubble burning in neighbouring states and trapping of dust and polluting gases close to the surface. (HT Archive)

The Delhi government is planning to trial cloud-seeding to trigger artificial rain in the Capital between October 9 and 11, officials aware of the matter said, confirming that the Directorate General of Civil Aviation (DGCA) issued clearance for the trials anytime between October 1 and 30.

Environment minister Manjinder Singh Sirsa said the clearance was given to IIT Kanpur, which will operate the aircraft. The trial is likely to be done in north Delhi, with an aircraft being flown from the Hindon airbase.

“To provide relief to Delhiites from air pollution through cloud-seeding or artificial rain, the government has received permission to do so between October 1 and November 30. The trial run will be held in north Delhi and IIT Kanpur’s Cessna aircraft will be flown from the Hindon airbase. I want to thank Delhi chief minister Rekha Gupta for this,” said Sirsa in a video released on Wednesday evening.

Cloud seeding is a weather modification technique that improves a cloud’s ability to produce rain. Experts, however, have long stressed that artificial rain is neither a viable short-term nor long-term solution for pollution control, with funds best diverted elsewhere.

Delhi-NCR suffers from heavy pollution in winter due to a combination of meteorological factors, stubble burning in neighbouring states and trapping of dust and polluting gases close to the surface.

Sirsa said when Delhi whenever pollution spikes, Delhi can make use of this Cessna aircraft and provide immediate relief to people.

The minister told HT that while the trial can be done anytime in October or November, a tentative period of October 9-11 has been earmarked. “It will obviously depend on the meteorological conditions too. The India Meteorological Department (IMD) has told us they will be able to give us a forecast three days in advance and if conditions are ideal for seeding, we will proceed with it,” Sirsa said.

The permission letter by DGCA, dated September 23, a copy of which HT has seen, said IIT Kanpur—the agency executing the project—will have to comply with certain conditions, chiefly no flying over restricted and prohibited areas, no aerial photography or survey, no involvement of a foreign crew and taking prior permission from air-traffic control (ATC) units in the vicinity.

“M/s Department of Aerospace Engineering, Indian Institute of Technology, Kanpur is hereby permitted to conduct cloud seeding activity in accordance with the approved operations manuals and operations specifications, using aircraft bearing registration no VT-IIT (Cessna 206-H) for a period from October 1 to November 30, 2025…” the DGCA letter read.

According to IIT Kanpur, nimbostratus clouds—which occur at altitudes between 500 and 6,000 metres above ground level—are best suited for cloud-seeding. These clouds must also contain at least 50% moisture content for the process to work. The moisture enables silver iodide (AgI) and other particles to initiate microphysical changes in the cloud, encouraging the formation of ice crystals or raindrops.

The trials were initially scheduled between July 4 and 11, but was deferred till late August and early September due to the onset of the southwest monsoon. This second deadline was also deferred due to rainfall, but is likely to take place in October as the southwest monsoon officially withdrew from the region on September 24.