China is running out of cloud-seeding shells after pounding the skies with a massive barrage to ease the worst drought that parts of the Yangtze delta have experienced for more than 100 years.
One of the country's biggest manufacturers of the weather-modifying ordnance said its warehouses were empty despite raising production by 30%, operating on weekends and adding two hours to shift times.
Workers on the assembly lines of Jiangxi Gangsi encase catalytic chemicals – usually silver iodide or liquid nitrogen – in shells, which are fired by cannon or dropped from aircraft, to create water droplets in clouds that will fall as rain.
Since 2000, the company has played a key role in China's weather-modification programme, thought to be the world's biggest, with an annual budget of £65m and offices in 30 provinces.
It is one of the nation's biggest makers of cloud-seeding shells, but company managers told the Guardian that they have struggled to meet a surge of demand during an unusually hot, dry spring.
"There is demand but not enough supply. This year is special," said Gu Jiangjun, a sales manager. "We normally produce 3,000 shells a month but now we are aiming for 4,000 to 5,000."
Even for a country that is used to drought, this year's arid spell has been shocking because of its duration and location: the Yangtze region is usually considered one of the lushest in China.
But Asia's greatest river is shrinking and shallowing, along with many of the lakes around it.
Shanghai is in its longest dry spell for 138 years, according to People's Daily.
Further upstream, Hunan is suffering the worst drought since 1910, affecting water supplies for 1.1 million people and 157 urban areas.
Television bulletins and newspapers are filled with images of dead fish, stranded ships and dry river beds.
Hydropower production has been slashed and vast swaths of paddy fields are parched.
The Three Gorges dam has been forced to cut hydropower generation and open its sluice gates to provide more water to downstream areas.
Recent cloudbursts – some precipitated by weather-modifying techniques – have raised hopes that the rainy season may finally have arrived.
But the China Meteorological Administration forecasts a short, sharp – and possibly dangerous – flood season, amid a long, hot summer.
Agency officials encouraged local governments to make continued use of weather-modifying techniques.
"We attach great importance to artificial rainfall in the effort to ease the drought," said the administration's vice director, Chen Zhenlin.
Chinese scientists claim that cloud-seeding can increase precipitation in targeted areas by 10-15%.
However, production of the shells may be hindered by government price controls.
Each cloud-seeding shell costs about 1,000 yuan (£94) – a figure that has been set since 2000, which means there is little financial incentive to boost production.
"We proposed a price increase to our senior executives," said Gu. "They sent a team to investigate the cost-production capacity. But these things take time."
Additional reporting by Cecily Huang
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