Cloud Seeding with Silver Iodide is Back

Cloud seeding – a silver-based technology used worldwide

for more than 50 years to increase rainfall – is making a

comeback.

For example, some drought areas in Texas are boosting rainfall

by about fifteen percent annually, an additional two inches,

due to cloud seeding, according to the West Texas Weather

Modification Association, a rain enhancement group based in

the City of San Angelo.

Other U.S. states are currently seeding or considering official

programs, including Arizona, Idaho, California, and Colorado,

although local jurisdictions often cloud seed independently.

Mexican officials have commenced seeding in five states.

Dubai, a city in the United Arab Emirates, has cloud seeded,

and last year, China, which has the world’s most active

clouding seeding programs, used it to help replenish the

Yangtse river basin, areas of which are in drought conditions.

In total, more than a dozen countries have cloud seeding

efforts.

In a twist, Chinese authorities seeded clouds prior to

the Beijing Olympics in 2008 to drain moisture from clouds

before the games so athletes would not compete in wet

weather.

Cloud seeding is straightforward. Rods or particles made of

silver iodide are floated into the air or dropped from planes

into clouds. The silver iodide acts as a nucleus to which

moisture can adhere and when the particles get heavy enough

they fall as raindrops, or snow if the temperatures are cold

enough.

Some scientists say that measuring the effectiveness of cloud

seeding is difficult, as it’s often impossible to know if the

cloud seeding effort was the cause of rain or if clouds were

ready to give up their moisture. Nevertheless, it’s clear that

more jurisdictions are looking to cloud seeding as a way to

mitigate the effects of climate change.