Yu is one of 37,000 peasants enlisted by the Chinese government to help produce rain in parched areas.

The 45-year-old farmer works with China's other trigger-happy rain men to water the crops, break up damaging hailstorms and put out forest fires. After a sandstorm blew through the capital in May, he lobbed shells and rockets skyward to coax rains that washed sand and grit from city streets.

Now Yu and the other rainmakers face their toughest challenge: making sure it stays dry for the opening ceremony of the 2008 Beijing Olympic Games.

The idea is for the peasant gunners to work with meteorologists watching radar in the capital. Together, they will hunt pregnant rain clouds and pound them with rockets containing silver iodide.

The hope is that any moisture will fall before the clouds can threaten the parade of athletes and lighting of the Olympic flame at the new National Stadium.

Yu, who wears a green military jacket and helmet in his gunner's seat, is already feeling pressure to perform. "The whole world will be watching the ceremony," he says. "We must guarantee its success."

In August, the Beijing Weather Modification Office will place the area's 20 firing sites on standby for a major test. In the Fragrant Hills west of Beijing, Yu and six others at the Man-Made Hail-Prevention and Rain-Increasing Work Station will be at the ready, manning four anti-aircraft batteries, which are army castoffs from the 1960s.

Yu's wife will talk to Beijing by walkie-talkie, getting the all-clear from aviation authorities and relaying the firing order from the meteorologists. Yu says he hopes to dissipate any clouds completely, increasing the barrage and concentrating his fire if necessary.

Two summers from now, "if rain clouds are headed toward the Olympic stadium, we will intercept them," says Zhang Qiang, a "weather modifier" at the Beijing Meteorological Bureau who will issue the command.

The U.S. pioneered cloud-seeding in the 1940s and '50s, but the government has cooled on its effectiveness, leaving the field to specialist companies. In China, among the most water-poor nations, the state tries to squeeze every drop from above.

"China has the largest rainmaking (operation) in the world," ahead of Russia and Israel, says professor Wang Guanghe, a 20-year rainmaking veteran at China's Meteorological Sciences Academy. "Each province reports results to us of between 10% to 25%" additional rainfall.

The forecast calls for more rain. China's five-year plan urges an increase in man-made precipitation. Central planners want an additional 65 billion cubic yards a year ¡ª nearly enough to fill the Yellow River, the country's second-largest river.

China began cloud-busting in 1958. Now "it is increasing every year," says Wang, who cites the drought plaguing northern China as the main reason to fire rain-inducing shells or soar into the skies in cloud-seeding airplanes.

Older generations of Chinese used to beat bells to pray for rain, Yu recalls. Today, he puts his faith in cigarette-sized sticks of chemicals loaded inside rockets and shells. "Every time we fire, it rains ¡ª lightly or heavily," says the farmer, who earns $125 a month during the May-to-September firing season. "At first, the other villagers didn't believe we could make it rain, but most accept it now."

Zhang, the Beijing meteorologist, says most farmers see the benefit of cloud-seeding and welcome chemically induced rains. Five years ago, a storm near the capital killed 139 ducks, crushing them with hailstones. Today, such incidents are rare, she says.