Airplanes Can Make it Rain

Humans can encourage rain or snow by "seeding" clouds by dispersing small particles into the atmosphere. These particles act as nuclei onto which droplets of liquid water inside clouds can freeze, producing ice crystals that, when large enough, fall to Earth in the form of snow or rain. These droplets often exist in a "supercooled" state at temperatures as low as –38 °C and the introduction of particles into clouds raises this minimum temperature. Due to this process which has been noticed in recent years, there is more precipitation around airports. 


For more information go to http://physicsworld.com/cws/article/news/46388

Picture Courtesy of Eric Zrubek and Michael Carmody