A group of scientists and researchers are figuring out whether drones can make it rain. The science is called cloud seeding. Drone America performed the test flight under an FAA agreement in partnership with the NIAS, Nevada Institute for Autonomous Systems. Drones are used in fields like news coverage, aerial photography, surveillance and rescue operations.
In cloud seeding the microscopic particles of silver iodide are shot into existing clouds using land based generators or aircraft. Silver iodide causes supercooled water droplets to freeze in the clouds. The ice embryos interact with the surrounding water droplets and make them grow into snowflakes. Depending on the surface temperatures, they fall as snow or raindrops to the ground. In some situations, cloud seeding can also make the cloud to grow larger and last longer than it would have without the modification.
In case of the manned operations, pilots can only seed from above the clouds, else they risk flying into mountainsides. Also, the ground operations are geographically spotty. So cloud seeding from the Earth can be inconsistent. On the other hand, Drones can fly in or below cloud cover at slower speeds, by distributing the silver iodide evenly.
Still, drones would be no silver bullet for the West’s drought misery. Generally, silver iodide is harmless but can cause damage to people when it is charged or ionized. It means seeding in the middle of stormy conditions is out of the question. In order to seed them, clouds must also be in the skies, so cloudless days rule out seeding opportunities too. Although, conditions between those extremes could be right for the drones.
The goal is to help a cloud’s ability to produce and enhance precipitation. The presence of storms are optimal, weather conditions need to be right for this to take place. The operation has been around for decades and normally requires a piloted aircraft flying into a storm. Presently, around 60 countries on five continents are using the process of cloud seeding to improve rainfall, mainly for reservoirs, watershed, and agriculture.
China has created artificial rain using drones for the first time successfully. It is announced that the drone has a flight time of about 125 to 250 minutes with a maximum payload of 50 kilograms. The unmanned aerial vehicle can be examined and controlled in real-time by the operators.
With the Desert Research Institute, the Nevada Institute of Autonomous Systems has organized the tests with unmanned drones. They plan to have drones conduct cloud seeding flights in the future. The Governor of Nevada’s office has helped fund for the project to be established.
Watch a video of how cloud seeding makes it rain artificially