Hong Kong(CNN) China this week revealed plans to drastically expand an experimental weather modification program to cover an area of over 5.5 million square kilometers (2.1 million square miles) -- more than 1.5 times the total size of India.
According to a statement from the State Council, China will have a "developed weather modification system" by 2025, thanks to breakthroughs in fundamental research and key technologies, as well as improvements in "comprehensive prevention against safety risks."
In the next five years, the total area covered by artificial rain or snowfall will reach 5.5 million sq km, while over 580,000 sq km (224,000 sq miles) will be covered by hail suppression technologies. The statement added that the program will help with disaster relief, agricultural production, emergency responses to forest and grassland fires, and dealing with unusually high temperatures or droughts.
China has long sought to control the weather to protect farming areas and to ensure clear skies for key events -- it seeded clouds ahead of the 2008 Beijing Olympics to reduce smog and avoid rain ahead of the competition. Key political meetings held in the Chinese capital are notorious for enjoying beautiful clear skies, thanks both to weather modification and the shutting down of nearby factories.
As a concept, cloud seeding has been around for decades. It works by injecting small amounts of silver iodide into clouds with a lot of moisture, which then condenses around the new particles, becoming heavier and eventually falling as precipitation.
A study funded by the US National Science Foundation, published earlier this year, found that "cloud seeding can boost snowfall across a wide area if the atmospheric conditions are favorable." The study was one of the first to ascertain definitively that cloud seeding worked, as previously it had been difficult to distinguish precipitation created as a result of the practice from normal snowfall.
That uncertainty had not stopped China investing heavily in the technology: between 2012 and 2017, the country spent over $1.34 billion on various weather modification programs. Last year, according to state news agency Xinhua, weather modification helped reduce 70% of hail damage in China's western region of Xinjiang, a key agricultural area.
And while other countries have also invested in cloud seeding, including the US, China's enthusiasm for the technology has created some alarm, particularly in neighboring India, where agriculture is heavily dependent on the monsoon, which has already been disrupted and become less predictable as a result of climate change.
India and China recently faced off along their shared -- and hotly disputed -- border in the Himalayas, with the two sides engaging in their bloodiest clash in decades earlier this year. For years, some in India have speculated that weather modification could potentially give China the edge in a future conflict, given the importance of conditions to any troop movements in the inhospitable mountain region.
Though the primary focus of Beijing's weather modification appears to be domestic, experts have warned there is the potential for impact beyond the country's borders.
In a paper last year, researchers at National Taiwan University said that the "lack of proper coordination of weather modification activity (could) lead to charges of 'rain stealing' between neighboring regions," both within China and with other countries. They also pointed to the lack of a "system of checks and balances to facilitate the implementation of potentially controversial projects."
"The scientific evidence and political justification for weather modification is not subject to debate or broad discussion (in China)," the authors wrote. "In addition, the leadership's propensity for technological intervention in taming different weather systems is rarely challenged by alternative viewpoints."
Some experts have speculated that success in weather modification could lead China to adopt more ambitious geoengineering projects, particularly as the country suffers from the effects of climate change. Radical solutions such as seeding the atmosphere with reflective particles could theoretically help reduce temperatures, but could also have major unforeseen consequences, and many experts fear what could happen were a country to experiment with such techniques.
"Without regulation, one country's efforts could affect other countries," according to Dhanasree Jayaram, a climate expert at the Manipal Academy of Higher Education in Karnataka, India.
"While China has not yet shown signs of 'unilaterally' deploying geoengineering projects on the ground, the scale of its weather modification and other massive engineering projects, including mega-dam projects (such as the Three Gorges), suggests China is willing to deploy large-scale geoengineering schemes to tackle the impacts of climate change and achieve its Paris targets."