Humanity has tamed rain (to some extent). The process of artificially inducing rain or cloud seeding has been around for almost 100 years. It works by adding substances such as dry ice, iodide salts or other salts to clouds that accelerate the creation of water droplets. Traditionally this is done using small aircraft flying into the clouds releasing the chemicals to kick-start the process.
Planes aren’t the only option though, people have experimented with rockets, and ground generators to get the salts up in the air to reach the clouds. The process isn’t cheap either, with costs going up to several million dollars for large scale, city-wide operations.
Drones have emerged as cost-effective alternatives to manned aircraft in several applications. What about cloud seeding? To do cloud seeding, you have to carry large amounts of material to high altitudes and disperse them among the clouds. To do it at the scale of airplanes, you need to carry a lot of salt and that’s difficult for drones with their limited payload capacity and size.
Also, using substances like silver iodide, the most popular choice for cloud seeding raises concerns from environmentalists. The health hazards from these substances are actively studied and still in debate. Researchers have been searching for alternatives to salt based cloud seeding and have come up with several solutions from using laser beams and less hazardous salts.
One such promising research from the UK uses electrical discharge to make water droplets in the clouds clump together and form larger ones that eventually fall down as rain. This also means that you don’t have to carry tonnes of salts to seed the clouds. You just need a device to create the electrical discharges and a battery to power it.
And that’s exactly what the UAE is doing with their recent experiment using drones to create rain
. To combat drought and a very hot summer, the UAE started a $15M project to create artificial rainfall in the country back in 2015. The project has been quite effective, with parts of the country receiving above average rainfall and cooling places that used to reach temperatures as high as 48 degrees Celsius.
The novel technique from the UK researchers coupled with drones pose a unique opportunity -
- No consumable material costs
- Low operational cost v/s manned aviation
- Easy to scale with multiple drones
- Localized targeting of rain over a given area