CHINA

Firing rockets to bring on the rain

North and eastern China have been struck by what looks like the worst drought in half a century. For the Olympic Games, Beijing launched missiles to fend off the rain. This time, they're trying to summon it. See the pictures and read more...

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North and eastern China have been struck by what looks like the worst drought in half a century. For the Olympic Games, Beijing launched missiles to fend off the rain. This time, they're trying to summon it.

Weather experts are divided over the cause of the drought, which is affecting more than 3.7 million farmers and two million cattle. Is it a sign of global warming? Or an effect of Beijing's ambitious use of hydraulic resources? In any case, the government has taken the situation in hand and declared, for the first time, a "maximum" state of emergency, granting 100 billion Yuan (around 11 billion euros) in aid to the most affected regions. They have also resorted to the use of mini-rockets, filled with a chemical product and launched from planes and trucks, to "charge" clouds. According to the Chinese press, around 1,200 of these agricultural missiles have been fired since January.

"The efficiency of artificial rainfall remains under dispute"

Laurent Li is a climatologist and director of the CNRS (National Centre of Scientific Research in France).

The mechanism is simple: the product used in the rockets, silver iodide, harnesses and enlarges the raindrops in the clouds. Once the size of the drops has been increased by ten, it will then rain.

The use of artificial rainfall is very common in China. I know the Chinese weather agency director, who's a great specialist and defender of the practice. But with other climatologists, the question of the efficiency of artificial rainfall remains under dispute. There was a lot of research done into it in the seventies and eighties [when it was used by Canada and the USSR]. Although the method was proved to produce condensation, it wasn't scientifically proved to produce rain. And seeing as firing rockets is an expensive practice, the idea was abandoned by most countries."

Photos posted on the Chinapic forum on 4 Feb. 08.