China's world's largest rainmaking system

China is developing the world's largest rainmaking system covering 1.6 million square kilometers, three times the size of Spain,South China Morning PostThe system, consisting of tens of thousands of fuel-burning chambers installed on the Tibetan Plateau, could increase rainfall in the region by up to 10 billion cubic meters per year, equivalent to 7% of China's total water consumption.

The solid fuel combustion chambers are located on steep mountaintops that catch the humid monsoon winds from South Asia. Scientists use them to create silver iodide particles, a cloud-forming agent with a rock-like crystalline structure. The moist monsoon winds combine with the silver iodide particles produced by the combustion chambers to form clouds that produce rain and snow.

"Currently, more than 500 combustion chambers have been deployed on mountaintops in Tibet, Xinjiang and some other areas for testing. The collected data shows very promising results," a researcher of the project shared.

The project is currently being developed by the China Aerospace Science and Technology Corporation. Scientists have designed and built the combustion chamber based on advanced rocket engine technology, allowing the system to efficiently burn solid fuel in an oxygen-deficient environment at altitudes of more than 5,000 meters above sea level. After many design improvements, the combustion chamber can operate in a near-vacuum environment for months, even years, without maintenance.

Rainmaking systems using solid fuel combustion chambers are not a new idea, some countries like the US have tested them on a small scale, but China is the first country to apply the technology on such a large scale.

The cost of developing a ground-based rainmaking system is relatively low compared to the airplane method. Each combustion chamber costs about $8,000 to build and install, and could be lower if mass-produced. Meanwhile, a rainmaking aircraft can cost hundreds of thousands of dollars and only on a small scale.

Tibet is known as Asia's largest freshwater reserve with its huge glaciers and underground freshwater reserves. They are the main source of water for the continent's largest rivers such as the Yellow River, Yangtze River, Salween River and Brahmaputra River.