Two Cessna aircraft fitted with salt and silver iodide flares took off from Kanpur and Meerut on Tuesday to conduct cloud seeding trials aimed at inducing artificial rain over Delhi — part of a long-awaited plan to combat worsening air pollution in the national capital.

The flights, operated under the supervision of the Delhi government and IIT-Kanpur, marked the first-of-its-kind experiment to use artificial precipitation as a pollution control measure. However, the results were disappointing, with only minimal drizzle recorded in Noida (0.1 mm) and Greater Noida (0.2 mm).

The Tuesday trials

According to Delhi Environment Minister Manjinder Singh Sirsa, the first aircraft from Kanpur released eight salt-based flares, each weighing 2–2.5 kg, over areas including Burari, north Karol Bagh, and Mayur Vihar. The flight lasted about 30 minutes, during which each flare burned for around two minutes.

A second aircraft took off from Meerut at 3:55 pm, deploying eight flares at an altitude of 5,000–6,000 feet. It covered Khekra, Noida, Modinagar, and Meerut, among other areas.

Despite the effort, no substantial rainfall occurred, though officials noted a slight reduction in PM2.5 and PM10 levels at the trial sites.

Cost and funding

The two trials together cost the government around ₹1.28 crore. The Delhi Cabinet had approved a ₹3.21 crore budget for five trials, with each operation costing approximately ₹64 lakh.

IIT-Kanpur Director Manindra Agrawal explained that the process costs ₹20,000 per sq km, adding that a 1,000 sq km seeding operation would cost around ₹2 crore. If carried out through winter, the total cost could reach ₹25–30 crore, a figure Agrawal called “reasonable” compared to Delhi’s total spending on pollution control.

Why it didn’t work

Meteorological conditions played a major role in the limited success. According to the India Meteorological Department (IMD), the moisture content in clouds on Tuesday was just 10–15%, well below the ideal level for cloud seeding.

“The possibility of rain with such low moisture content is not very high,” Agrawal told NDTV, noting that sufficient humidity is key for condensation and rainfall formation.

What’s next

The Delhi government and IIT-Kanpur plan to conduct 9–10 more trials in the coming days, weather permitting. A trial scheduled for Wednesday was put on hold due to insufficient cloud moisture.

Officials remain optimistic that subsequent attempts—if timed with better atmospheric conditions—may yield more significant results.