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Authorities in Indian capital Delhi unsuccessfully carried out a cloud seeding trial, which is the science of altering clouds to make rains, to tackle the city’s worsening air pollution on Tuesday.<\/p>\n\n\n\n
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.<\/p>\n\n\n\n
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.<\/p>\n\n\n\n
But the attempt – the first in 50 years – was “not completely successful” due to the lack of moisture in the air.<\/p>\n\n\n\n
Over the past two weeks, 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 – has been hovering between 300 and 400, which is nearly 20 times the acceptable limit.<\/p>\n\n\n\n
On Tuesday, authorities used a Cessna aircraft to release fire flares containing silver iodide and sodium chloride into the atmosphere to trigger rainfall.<\/p>\n\n\n\n
In a statement, IIT Kanpur said that despite the lack of rain, there had been a measurable reduction in particulate matter because of Tuesday’s experiment, “indicating that even under limited moisture conditions, cloud seeding can contribute to improved air quality”.<\/p>\n\n\n\n