Authorities in Indian capital Delhi unsuccessfully carried out in October 2025 a cloud seeding trial, which is the technique of altering clouds to make rain, to tackle the city’s worsening air pollution.

[What is Cloud Seeding?] Cloud seeding is done by firing small particles – usually silver iodide – into clouds to produce rain. The technique is used around the world, but experts doubt its efficacy as a long-term air pollution control measure. A team of the Indian Institute of Technology (IIT) Kanpur and the Delhi government carried out the trial over several neighbourhoods, as thick smog enveloped the city. But the attempt – the first in 53 years – was “not completely successful” due to the lack of moisture in the air. As a result, Delhi’s Air Quality Index (AQI) – which measures the level of PM 2.5 or fine particulate matter in the air that can clog lungs – is still hovering between 300 and 400, which is nearly 20 times the acceptable limit…

Delhi’s first cloud-seeding experiment was carried out in 1957, followed by another attempt in 1972, according to the Indian Institute of Tropical Meteorology. While those experiments were aimed at drought management, this was the first indigenous effort at cloud seeding to control pollution.

China has boasted about its success to manage rains before hosting the Olympics, with Beijing using rockets, cannons and drones to do cloud seeding. However, in the United Arab Emirates, questions over the technique were raised, following floods in Dubai in 2024.

Excerpt from Abhishek Dey, Why Delhi’s experiment to fix toxic smog with artificial rain failed, BBC, Oct. 29, 2025