Beijing to stop Olympic rain *Weather Control

June 6, 2006

Beijing bid to stop Olympic rain

By Marianne Bray

CNN

HONG KONG, China (CNN) -- Beijing will be shooting for the stars in a bid to starve off downpours when it hosts the Olympics Games in 2008.

Using an arsenal of rockets, artillery and aircraft, China will try to blast the clouds out of the sky, a meteorologist from Beijing told a Hong Kong newspaper, through a technique which falls under the umbrella of "cloud seeding."

"We sometimes turn a cloudy day into a dry and sunny one by shooting the clouds less intensively than when we make rain," head meteorologist Mian Donglian for the Beijing municipal weather bureau told The South China Morning Post.

By shooting shells containing chemicals like silver iodide, or dry ice into the sky, scientists say they can create rain. China has gone so far as to set up a weather modification office that is in charge of such an endeavor.

When the guns go off, they scatter crystals that attract water droplets in the cloud, making them grow faster, said climate and weather expert Johnny Chan from the City University of Hong Kong. The crystals become heavy and fall as raindrops, he said.

Planes, too, can be used to drop chemicals onto clouds to manipulate the weather.

In the case of the Olympics, climate experts will pore over satellite images to find ways to dissolve the clouds rather than make it rain.

"Scientists fly an airplane, sampling the cloud ... to see if there is potential for it to work, and if it is likely to work, they will shoot the gun," Chan said.

Ill winds that blow

Giving Mother Nature a helping hand is not a new phenomenon for China.

For decades China has been a rainmaker for its northern regions, where winds from the Gobi desert leave farmers high and dry and coat the parched capital of 15 million people with frequent sand storms.

But the Weather Modification Office is charged with among other things, dousing the city with rain to get rid of pollution, sandstorms, hail and fires and getting water to arid areas.

Just last Thursday the office claimed to have opened the heavens by firing off 163 cigarette-sized sticks and seven rockets into the sky, bringing as much as 11.2 millimeters of water to a parched, dusty and polluted Beijing, in the heaviest rainfall so far this spring.

The United States started making rain in the 1950s, but later gave up because they could not work out whether the seeding produced more rain, Chan said. China now boasts it is the world's leading rainmaker.

It has created enough rain during the past five years to fill the Yellow River, the nation's second largest, four times over, State-run news agency Xinhua says.

Between 2001 and 2005, nearly 3,000 flights triggered 210 billion cubic meters of water over an area making up nearly a third of China's territory, an official from the National Meteorological Bureau told Xinhua.

An army of more than 3,000 rainmakers have at their disposal 7,000 cannons and 4,687 rocket launchers to coax more rain from clouds across China.

Amid these staggering figures, Chan warns the science for cloud seeding is difficult to prove scientifically, because experts don't know how much rain would have fallen without it.

"The problem is you don't have two identical clouds, where you seed one and not seed the other to compare the result," he says.

But he adds, if you do want rain, you might as well try to get it.

"You have nothing to lose. China wants rain, the cloud is in the sky and it could give them some water. It's not strictly scientific but it's a strategy to take."

China's meteorological office has announced in its latest five-year plan it wants to produce more rain in the future.

And if all goes to plan, none of it will be falling when the Olympics will be held two years from now.

Source

-------------------------

user posted image