According to an ancient myth, once there were 10 suns in the sky, heat scorched the Earth and dried up people's blood. The people were saved when hero Hou Yi rose up to shoot nine suns out of the sky with his magic arrows.
In face of severe droughts, people in northwest China once again have looked toward the heavens, trying to find answers like their legendary ancestor. But their target is no longer the sun and the arrows have been replaced with artificial precipitation shells.
"People use the shells to harvest rainfall from the juicy clouds," said China Meteorological Bureau official Zhang Qiang on Wednesday. He spoke at the ongoing International Symposium on Arid Climate Change in Lanzhou, capital of Gansu Province.
"It is a very effective way to solve enduring droughts in western regions of the country," he said.
Zhang and the Lanzhou Arid Climate Research Institute are involved in an ambitious "heaven water seeking program," a part of the West Development Scientific and Technological Program Package by the Ministry of Science and Technology.
The program has initiated research on clouds above Qilian Mountain and will provide solutions on utilizing water resources in the air.
Experts said the aim of the program is to increase precipitation 10 to 15 percent in the mountainous region.
Maximum precipitation in the province's mountainous area is 600 millimeters, according to the institute.
"If the program goes smoothly, it will bring 370 million cubic meters more water to Qilian Mountain and the continental rivers of nearby Hexi Corridor," Zhang said. "This will greatly improve the environment and may lead to profits of 600 million yuan (US$72.6 million)."
Qi Xinhui, a senior engineer from the provincial flood control and drought relief headquarters, said: "China defines 100 million cubic meters of water to be a large-scale reservoir and the program will bring nearly four large-scale reservoirs to the province."
The "heaven water seeking program" is not restricted to Gansu, but will also be implemented in Shaanxi Province and the Ningxia Hui Autonomous Region.
In these regions, per capita water resources are below 1,000 tons per person, less than half of the national average. The country's per capita water resources amount to 2,200 tons, only 25 percent of the world's average.
Liu Chunzhen from the Ministry of Water Resources said the continuing drought and unplanned water use contribute to shortages in the northwest.
To ease the situation, governments have already started creating artificial precipitation.
Gansu's artificial precipitation office said the province has established more than 300 sites for artificial rainfall or snowfall. It will conduct more than 1,000 operations every year with the help of rockets, cannons and airplanes.
An additional 1 billion cubic meters of precipitation has fallen on Gansu since last year due to the program.
Zhang said the development of cloud water resources will bring provinces "invisible and long-term benefits."
It will not only reduce overuse of underground water resources but is also conducive to preserving the "feeble" ecological environment in arid regions.
People are also noticing the change. Lanzhou resident Zhao Weibing said: "The air was severely polluted in the winter, however, it has changed for the better when artificial precipitation is frequently performed."
Zhang said the program may be expanded.