Science geeks make rain with lasers

Scientists at the University of Geneva have developed a new method of creating rainfall through the use of lasers which could see artificially produced clouds supply water to countries severely affected by drought.

It could replace the older ‘cloud seeding’ method which has been the subject of 50 years of development, according to Nature.com.  The previous method involved firing a red laser to ionise the air, causing water droplets to form a cloud. Then, in a light show worthy of Gallic pyramid illuminator Jean Michel Jarre, a green laser would be used to highlight the cloud before rockets containing silver iodide particles would finally condensed the clouds into rain.  

However this method was deemed to be ineffective and potentially dangerous according to Dr Jerome Kasparian.  “The problem is, it’s still not clear that cloud seeding works efficiently. There are also worries about how safe adding silver iodide particles into the air is for the environment.”

With this in mind Dr Kasparian looked to develop a more environmentally friendly method.  It was found that by firing a laser through an atmospheric chamber Kasparian was able to ionize nitrogen and oxygen molecules which replicated the silver iodide effect as a natural condensation anchor.

Once the method had proved effective it was successfully tested away from a laboratory environment for the first time over the skies of Berlin. But while the team were able to produce some evidence of rainfall, particularly in high humidity, it was noted that it would be some time before it would be possible to create sustained periods of heavy rainfall.

“We can only create condensation along the laser channel, so we won’t be going out and making rain tomorrow.”