China builds large rainmaking system in Tibetan plateau

Asia's largest freshwater reserve is at risk of severe drought due to reduced rainfall and rising temperatures. In response, China is implementing cloud seeding by building combustion chambers that convert solid fuel into silver iodide. These chambers are placed on mountainsides to induce precipitation over a vast area, three times the size of Spain. So far, 500 chambers have been deployed in Tibet and Xinjiang.

What environmental issues are prompting China's cloud seeding initiatives?

How many combustion chambers have been deployed in Tibet and Xinjiang?