Last year we reported that researchers at Switzerland’s University of Geneva had come up with an interesting way of making it rain – by shooting lasers high up into the sky. At the time it seemed like science fiction, but now it is science fact after the team successfully finished testing the technology around Lake Geneva.
The technique, called laser-assisted water condensation, sees laser beams create water droplets in the air allowing mankind to, for the first time, determine where and when rain falls. This could solve drought, famine and all sorts of climate change catastrophes. Except storms.
The Swiss team successfully demonstrated the technique in field tests after setting up a mobile laser laboratory near Lake Geneva. The team fired lasers for 133 hours, during which time the pulses created nitric acid particles in the air. These ‘stuck’ to water molecules, which in turn turned to droplets. The larger size droplets were therefore not able to re-evaporate and within seconds, these grew to drops a few thousandths of a millimeter in diameter.
Now it should be noted that these droplets were too small to fall as rain, but it has proved to scientists that the technology has merit.
“We have not yet generated raindrops – they are too small and too light to fall as rain. To get rain, we will need particles a hundred times the size, so they are heavy enough to fall,” said Jérôme Kasparian, a physicist at the University of Geneva, writing in the journal Nature Communications.
The method actually has the potential to stop storms. Instead of creating rain, the lasers could create so many tiny droplets in the air that none will grow large enough to fall. “Maybe one day this could be a way to attenuate the monsoon or reduce flooding in certain areas,” Kasparian said.
So what are the technology’s limits? Currently, the team’s Teramobile laser can only shoot beams of light several miles into the sky. While this puts it within reach of areas of the atmosphere where water normally condenses, modifications will need to be made so that rain is created over larger areas. But when that day comes, in theory, we could have crop fields in deserts, where arid land gives new life and guaranteed harvests.
Nice one, science!
Via The Guardian