City Scale Water spraying from skyscrapers would be artificial rain to clean air pollution for mitigating haze in China

In the past 30 years, China has suffered from air pollution and heavy haze created by fast industrial growth and economic expansion. An Environmental Chemistry Letter research journal article reviews the techniques for remediation of air pollution. A geoengineering method is proposed for mitigating air pollution and haze in China’s cities by using water to scavenge air pollution. Here, water should be sprayed into the atmosphere like watering garden. The scientific rationale and mechanism for the geoengineering scheme are explained. It is found that precipitation scavenging coefficients are very sensitive to the size distributions of both aerosol and raindrops, and rain intensity. I found that the water spray geoengineering method can reduce the PM2.5 pollution in the atmosphere very efficiently to 35 μg m−3 level [World Health Organization level which is about ten times less than the bad days in China's major cities] in a very short time period from few minutes to hours or days, depending on the precipitation characteristics. In addition, the water spray geoengineering method has excellent advantages such as rapidity, already available technology, low cost, and a nature-like process. This proposed geoengineering scheme can be one of the answers for fighting air pollution in the cities globally.

China has planned to spend hundreds of billions to fight air pollution. Deploying these systems on a large scale might only be a few million per skyscraper.

Research and experiments are underway to design a suitable water delivery system for this plan. The system would have the added benefit of improving the high rise fire fighting capabilities.

If you can spend half an hour watering your garden, you can also spend 30 minutes watering your ambient atmosphere to keep the air clean with this technique. China’s air pollution was responsible for 350,000 to 500,000 deaths in 2013. In a December 2013 paper published in Lancet, Zhu, whose term as Health minister ended last year, called China’s polluted air the “fourth biggest threat to the health of Chinese people” behind heart disease, dietary risk and smoking.

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