As millions of people in Asia choke under polluted skies, authorities have turned to water-dispersing drones and outdoor air purifiers to improve air quality, while companies have tried to cash in by selling everything from canned air to lung-purifying teas.
New Delhi - the world's most polluted major city - tried in 2017 to use helicopters to sprinkle water over the city, but the choppers were not able to fly due to low visibility caused by smog. An attempt by South Korea to create artificial rain to tackle air pollution in January failed, after an aircraft sent to seed clouds with silver iodide only produced several minutes of misty rain.The northern Chinese city of Xi’an is experimenting with a giant air purifier the size of an industrial smokestack which can reduce PM2.5 concentration by 15 percent within 10 square kilometres, according to researchers.
New Delhi last year announced a plan to install huge air purifiers at traffic intersections and mount air filters on the roofs of buses that trap pollutants as they move, according to Hindustan Times.During particularly bad spates of air pollution, which tend to come during the winter, residents in smoggy Chinese cities escape to cleaner places, such as resorts in the south of the country, for a temporary break and return after it has cleared.