China needs more water. So it’s building a rain-making network three times the size of Spain
Vast system of chambers on Tibetan plateau could send enough particles into the atmosphere to allow extensive clouds to form.
China is testing cutting-edge defence technology to develop a powerful yet relatively low-cost weather modification system to bring substantially more rain to the Tibetan plateau, Asia’s biggest freshwater reserve.
The system, which involves an enormous network of fuel-burning chambers installed high up on the Tibetan mountains, could increase rainfall in the region by up to 10 billion cubic metres a year – about 7 per cent of China’s total water consumption – according to researchers involved in the project.
Tens of thousands of chambers will be built at selected locations across the Tibetan plateau to produce rainfall over a total area of about 1.6 million square kilometres (620,000 square miles), or three times the size of Spain. It will be the world’s biggest such project.
The chambers burn solid fuel to produce silver iodide, a cloud-seeding agent with a crystalline structure much like ice.
The chambers stand on steep mountain ridges facing the moist monsoon from south Asia. As wind hits the mountain, it produces an upward draft and sweeps the particles into the clouds to induce rain and snow.
“[So far,] more than 500 burners have been deployed on alpine slopes in Tibet, Xinjiang and other areas for experimental use. The data we have collected show very promising results,” a researcher working on the system told the South China Morning Post.
The system is being developed by the state-owned China Aerospace Science and Technology Corporation – a major space and defence contractor that is also leading other ambitious national projects, including lunar exploration and the construction of China’s space station.
Space scientists designed and constructed the chambers using cutting-edge military rocket engine technology, enabling them to safely and efficiently burn the high-density solid fuel in the oxygen-scarce environment at an altitude of over 5,000 metres (16,400 feet), according to the researcher who declined to be named due to the project’s sensitivity.
While the idea is not new – other countries like the United States have conducted similar tests on small sites – China is the first to attempt such a large-scale application of the technology.
The chambers’ daily operation will be guided by highly precise real-time data collected from a network of 30 small weather satellites monitoring monsoon activities over the Indian Ocean.
The ground-based network will also employ other cloud-seeding methods using planes, drones and artillery to maximise the effect of the weather modification system.
The gigantic glaciers and enormous underground reservoirs found on the Tibetan plateau, which is often referred to as Asia’s water tower, render it the source of most of the continent’s biggest rivers – including the Yellow, Yangtze, Mekong, Salween and Brahmaputra.
The rivers, which flow through China, India, Nepal, Laos, Myanmar and several other countries, are a lifeline to almost half of the world’s population.
But because of shortages across the continent, the Tibetan plateau is also seen as a potential flashpoint as Asian nations struggle to secure control over freshwater resources.
Despite the large volume of water-rich air currents that pass over the plateau each day, the plateau is one of the driest places on Earth. Most areas receive less than 10cm of rain a year. An area that sees less than 25cm of rain annually is defined as a desert by the US Geological Survey.
Rain is formed when moist air cools and collides with particles floating in the atmosphere, creating heavy water droplets.