July 29, 2004

THE anti-aircraft battery and rocket launcher at Xiangshan aim straight into a flight path that cuts over the north-western corner of the Chinese capital.

As Li Ruqing proudly shows off the weaponry, he casts an eye across the courtyard at a padlocked shed where chemical-tipped shells and missiles are stacked at the ready.

'There is a 30 per cent chance we'll use them tonight,' he says.

Mr Li, finger on the trigger, is no madman. Nor does he run a suburban gunnery range for China's air defences. He's a 'weather modifier' - his weapons disperse chemicals into the sky and his targets are waterlogged clouds.

Cloud seeding, as Mr Li's work is termed, is increasingly common in China, where a chronic drought grips the north and hailstones ruin countless acres of crops nationwide every year.

'Our main job,' he says with the focus of a seasoned field commander, 'is the prevention of hail... If there is hail heading for Beijing, this is the last line of defence.'

Mr Li commands three installations like Xiangshan, or Fragrant Hills, in north-western Beijing where, when the clouds are thick and when he's sure there are no planes overhead, he opens fire on the sky with special rockets to make it rain.

In the past, Chinese emperors sacrificed oxen and sheep to draw rains from the heavens. Today, Chinese statistics show that cloud seeding, which can also be done by aircraft, may be somewhat more effective.

This year, some city planners are talking about training their 'rain guns' on another enemy - the energy shortage that is hobbling China as its electricity-producing capacity struggles to keep up with the booming economy.

The idea: Make it rain during the dog days of summer to bring down the temperature and hopefully lower electricity consumption. Shanghai plans to give it a try and the idea has been broached in Beijing but not yet pursued.

The technique was tried last year in the southern province of Jiangxi, but the results were not publicised, said head of the National Weather Modification Office Chen Zhiyu. 'They say rainfall was really increased and the results were not bad.'

Even without precise statistics, the fact that cloud seeding is being talked about as a way to ease the electricity shortage is testament to the high appraisal of the technique in China.

Cloud seeding has been used for decades, but it has grown quickly since the 1990s. China suffered its worst drought in more than a decade in 2001.

From 1995 to last year, China spent 2.2 billion yuan (S$458 million) on cloud seeding nationwide and now there are 35,275 people in the business of making it rain, China Meteorological Administration statistics show.

Years of drought in northern China have even sparked reports that some towns were complaining of others stealing their rain by seeding clouds as they passed. Mr Li laughs off the idea, saying clouds hold more than enough rain to go around.

Last year alone, the state spent about 413 million yuan attacking clouds, using 30 planes, 3,800 rockets and 6,900 artillery shells, statistics show.

The administration says cloud seeding added more than 7.4 trillion cubic feet of rain from 1995 to last year.

Deputy director-general of the Beijing Weather Modification Office Zhang Qiang said cloud seeding had increased rainfall by 12.5 per cent in China's capital.

In Beijing, suffering drought for the sixth year running, weather modification officials have started using rain-making techniques to try to fill dwindling reservoirs. -- Reuters

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