Want Rain? Fire Laser!

“Water droplets have been created by shooting lasers into the air. The technique might be used to create or prevent rain…

While nothing can produce a downpour from dry air, the technique, called laser-assisted water condensation, might allow some control over where and when rain falls if the atmosphere is sufficiently humid.

Researchers demonstrated the technique in field tests after hauling a mobile laser laboratory the size of a small garage to the banks of the Rhône near lake Geneva in Switzerland.

Records from 133 hours of firings revealed that intense pulses of laser light created nitric acid particles in the air that behaved like atmospheric glue, binding water molecules together into droplets and preventing them from re-evaporating.

Within seconds, these grew into stable drops a few thousandths of a millimetre in diameter: too small to fall as rain, but large enough to encourage the scientists to press on with the work.”