Second cloud seeding trials fail in Delhi: Here's why it didn't work

Director of the Indian Institute of Technology Kanpur Manindra Agrawal said the latest cloud seeding attempt was "not completely successful" because the clouds lacked enough moisture

After more than five decades, Delhi carried out cloud seeding trials on Tuesday to create artificial rain in an effort to reduce rising pollution levels. The Delhi government and the Indian Institute of Technology (IIT) Kanpur jointly conducted the trials in areas such as Burari, Karol Bagh, Mayur Vihar, and Badli. However, the efforts failed as the India Meteorological Department (IMD) did not record any rainfall in the city.

Why cloud seeding failed in Delhi

According to an NDTV report, IIT Kanpur Director Manindra Agrawal said the attempt was “not completely successful” because the clouds lacked enough moisture. “For rain to form, moisture levels of at least 50 per cent are ideal,” he said. “Today’s clouds only had about 15–20 per cent moisture, which reduced the chances of rainfall.”

 

 

Despite low humidity, the operation gave researchers confidence that the technology could work under better weather conditions.

 

Agrawal said while there was no rain in Delhi, the trial helped the team gain experience for future operations. Two more flights will be conducted when suitable cloud conditions appear, he said. 

Cloud seeding attempts in Delhi

The second attempt was carried out using a Cessna aircraft, which flew from Meerut, releasing flares containing silver iodide and salt compounds into the clouds. Each flare burned for about two minutes. The goal was to trigger rain within 15 minutes to four hours of the exercise.

 

Meanwhile, the first round, conducted last week, released six flares at an altitude of around 4,000 feet above ground level, with a burn time of 18.5 minutes.

What the government said

In a report released late on Tuesday evening, the Delhi government said there was a slight drop in air pollution levels in areas where the trial was conducted, news agency PTI reported.

 

PM 2.5 levels fell slightly in Mayur Vihar, Karol Bagh, and Burari after the seeding process. Small traces of rain were recorded in Noida (0.1 mm) and Greater Noida (0.2 mm).

 

Delhi Environment Minister Manjinder Singh Sirsa said this was a “major scientific step” to combat pollution and added that more trials, up to 10 in total, are planned till February if results are encouraging.

 

#WATCH | Delhi CM Rekha Gupta says, "Cloud seeding is a necessity for Delhi and is the first experiment of its kind. We want to try it in Delhi to see if it can help us control this very serious environmental problem. So the blessings of the people of Delhi are with the… pic.twitter.com/odGavXxe64

— ANI (@ANI) October 24, 2025

When will the next trial take place

A third round of cloud seeding is expected to take place later this week once the IMD confirms the presence of suitable clouds, with more similar trials planned in the coming days. Sirsa told ANI that IIT Kanpur has been collecting large-scale samples during the trials and would submit a detailed report soon.