(note: Although the person featured in the following article is now deceased, below are excerpts from a 2003 Business Week Online Archives PDF)
Rainmaking Has Its True Believers -- And Skeptics
Science and Technology Section
China has 35,000 people engaged in weather management, and it spends $40 million a year on alleviating droughts or stemming hail that would damage crops. (Google translated website: Chinese Academy of Meteorological Sciences)
Russian officials claim to order up clear skies for Moscow's May Day parade. It's done by saturating clouds with dry ice, producing so many tiny droplets that drops can't grow big enough to fall as rain -- at least for a while. (Russian Federation Meteorological site)
In the U.S., though, there is no clear consensus on how well such techniques work, or if they work at all. In the1970s the U.S. plowed $20 million a year into cloud-seeding research, but almost all federal funding has since dried up.
Nevertheless, dozens of state, local, and private operations continue in 10 states, including California, (PDF of California precipitation enhancement projects) Idaho, Nevada, and Utah. Vail Mountain in Colorado and many other ski resorts pay for cloud seeding, and Vail estimates that teasing more precipitation from clouds boosts its snowpack by 15%.
While modern rainmakers and their clients believe the technology works, convincing the skeptics will be difficult.
For the statistical proof that science normally requires, the data on weather-modification efforts might need to span 60 years or more -- at least two of earth's 30-year weather cycles. Only a few of the cloud-seeding programs, including one in Saudi Arabia and one in Wyoming, are now collecting rigorous data.
Perhaps the most controversial technology comes from Russia and Mexico. (translated ELAT site)
In 1996, Russian space and weather control scientists hooked up with Gianfranco Bisiacchi, then head of Mexico's space efforts, and founded Electrificación Local de la Atmosfera Terrestre (ELAT)
Nominal results from the three ground stations set up by ELAT in 1998 were so impressive -- rainfall was reported to increase by as much as 30% -- that Mexican state governments were soon clamoring for more facilities. There are now 13, with additional ones being installed in Baja California and the state of Puebla.
ELAT claims credit for ending the severe drought in northern Mexico. Since 2000, says Bisiacchi, the amount of annual rain in the region has been "30% to 35% greater than what it was during the 1990s. In fact, the lakes of the region that were dry are now full."
When operations in the northern states of Sonora and Chihuahua started in 2004, he adds, most lakes were around 8% full. "We've now gone to levels of 85% to 90% -- in just one year.
ELAT says its technology is more efficient than regular cloud-seeding methods. "Milking" clouds is usually done by sprinkling them with particles of silver iodide. The particles provide a site where the clouds' ice crystals accumulate in clumps too heavy to stay aloft.
Bisiacchi and his team take a different tack: They generate charged ions on the ground and point them skyward. That, they claim, fosters clumping on both airborne dust particles and ice crystals touched by a charged ion.