Here’s how things would unfold if Sachchida Nand Tripathi has his way.
During winter, an ISRO aircraft flying three kilometres above ground uses its flare launchers to shoot hygroscopic (water-inducing) salts at target clouds over Delhi-NCR. Updraughts—which can reach speeds of 50 metres a second in storm conditions, but average 5-8 m/s in summer months—may be absent this time of year. But here’s hoping they’re present, because these upward air currents will help disperse the salts. The salts serve as additional nuclei for precipitation to occur.
The outcome, hopes Tripathi, is that raindrops will form as a result, showering down on the national capital and bringing temporary respite from Delhi’s air pollution woes.