Ready, aim, fire and rain

In the beginning, the idea was to ease drought and improve harvests for Chinese farmers, but over the decades other functions have evolved such as firefighting, prevention of hailstorms, and replenishment of river heads and reservoirs. Artificial rain has also been used by some provinces to combat drought and sandstorms. In 2004, Shanghai decided to induce rain simply to lower the temperature during a prolonged heat wave to bring relief to an increasingly hot and sweaty urban populace.

And now China's weather officials have been charged with another important task: ensuring clear skies for the Summer Olympic Games next year.

Partly sunny here.