2 sorties, 16 flares: What happened, what didn't & at what cost | Delhi cloud seeding

Delhi Environment Minister Manjinder Singh Sirsa has said that the government has planned 9-10 such trials over the next few days.

Two Cessna aircraft fitted with salt-based and silver iodide flares took off on Tuesday, few hours apart — one from Kanpur, another from Meerut — to induce artificial rains in Delhi.

In this photo shared by Indian Institute of Technology, a plane takes off from Kanpur for New Delhi for a cloud seeding trial to combat air pollution in the capital, India, Tuesday, Oct. 28, 2025. (Indian Institute of Technology, Kanpur, via AP) (AP)

The aircraft, loaded with eight flares each, hovered over the northwest areas of the capital to conduct cloud seeding, in a first-of-its-kind measure to combat deteriorating air quality levels in the city.

The trials, however, failed to yield rainfall, barring minimal precipitation in Noida and Greater Noida. More such trials are planned in the coming days to induce artificial rain.

What happened on Tuesday?

Delhi Environment Minister Manjinder Singh Sirsa said two cloud seeding trials were conducted in collaboration with IIT-Kanpur, adding that more such exercises are in pipeline.

Delhi govt and IIT-Kanpur held two cloud seeding trials on Tuesday.

The first aircraft took off from Kanpur and covered areas such as Burari, north Karol Bagh, and Mayur Vihar. A total of eight flares were fired and the trial lasted for about half an hour.

"The Cessna aircraft took off from Kanpur. It released eight fire flares each weighing 2 to 2.5 kilograms and the trial lasted for half an hour. Each flare lasted for two to two-and-a-half minutes," Sirsa said in a video statement.

A second flight took off at 3:55 pm from Meerut, deploying eight flares at a higher altitude of around 5,000-6,000 feet. The flight covered areas, including Khekra, Burari, Mayur Vihar, Pavi Sadakpur, Noida, Bhojpur, Modinagar and Meerut.

Two trials cost over ₹1 crore

The first two trials to get Delhi to receive artificial rain costed the state government around ₹1.28 crore in total.

The Delhi Cabinet approved the cloud seeding project in May, allocating ₹3.21 crore for five trials, each trial costing roughly ₹64 lakh.

The cloud seeding as a measure to combat Delhi's pollution has long been awaited – and debated – ever since 2023, before it got the final go last week.

Did it succeed?

It depends. Though the trials failed to induce rain, they did help in reducing particulate matter at the locations where the cloud seeding process was carried out, the official government report said on Tuesday.

The Delhi government report said that the moisture content predicted by IMD was low, at around 10-15 per cent, which is not ideal for cloud seeding. However, there were two instances of minimal rain -- Noida at 4 pm (0.1 mm of rain) and Greater Noida at 4 pm (0.2 mm).

The report said that particulate matter -- PM2.5 and PM10 -- were directly impacted after the trials.

Math behind cost of cloud seeding

IIT-Kanpur Director Manindra Agrawal detailed the cost of cloud seeding and reasoned that the process behind artificial rain was not much compared to the money spent on pollution control measures.

He said that the cost of cloud seeding is roughly ₹20,000 per square kilometre.

"If we conduct the exercise over an area of 1,000 square kilometres, the cost would be around ₹2 crore," Agrawal said in a video statement.

Speaking on the future cloud seeding trials, he said that if the process continues over the entire winter period, considering that the clouds are present once in every ten days, the total cost would come to around ₹25 to ₹30 crore.

"That, in the overall scheme of things, is not a very large amount. The amount of money spent on pollution control in Delhi is quite large," the IIT-Kanpur director said, according to PTI.

What about future trials?

Delhi Environment Minister Manjinder Singh Sirsa has said that the government has planned 9-10 such trials over the next few days.

However, the atmospheric moisture remains a challenge.

Speaking on the latest trials, IIT Director Manindra Agrawal said that though there were clouds on Tuesday, the moisture content was not enough to induce rain.

"The clouds that are present today do not have very high moisture content. I was told that it was only 15-20%. So, the possibility of causing rain with such low moisture content is not very high," Agarwal told NDTV yesterday.

Another cloud seeding trial was scheduled for Wednesday, but it was put on hold.

IIT-Kanpur, in a statement, said the trial scheduled for Wednesday was put on hold due to insufficient moisture in the clouds.