The $19 million Tianhe Project — which translates into Sky River — is the world’s largest artificial rain experiment, which aims to divert excess water vapour above the Yangtze river basin towards drier parts of the country, according to local media.

Scientists from China’s Tsinghua and Qinghai Universities put forward the project in 2015, which requires constructing an artificial air corridor to carry the water vapour.

More recently, they have moved to develop satellites and rockets that would then monitor vapour presences and movement and redirect it to create precipitation.

Six satellites developed by the Shanghai Academy of Spaceflight Technology should be in operation by 2022 to guide the creation of an air corridor above Asia’s largest river, and to monitor the distribution of water vapour in the air, the People’s Daily reported earlier this month.

According to former Chinese premier Wen Jiabao, a water crisis could be the biggest threat to China’s rise as a superpower — undercutting the growth and stability so prized by the Government.

If the project is successful, it could divert 5 billion cubic metres of water annually to relieve China’s northern dry areas — however physicists from both China and Australia doubt its chances of success.

“I think ambitious is probably understating it a little bit,” ABC meteorologist and physicist Nate Byrne said.

“We’re talking about a huge amount of energy that would be required just to evaporate the water and that’s a job that’s undertaken by the sun normally.”

The latest developments follow a recent trend of projects that has seen China trying to engineer aspects of the natural environment.

Earlier this month, nuclear scientists reached an important milestone creating an “artificial sun” by harnessing energy from nuclear fusion, while last month, China announced it was in the process of creating “artificial moons” bright enough to replace city streetlights by 2020.

‘An absurd fantasy’

The exact science behind the plan is the subject of speculation and controversy in China.

A woman in China holding an umbrella in front of traffic.
PHOTO: Former premier Wen Jiabao said a water crisis could be the biggest threat to China’s rise as a superpower. (Flikr: Let Ideas Compete)

Several prominent physicists in China have questioned whether the project would work, choosing to air their concerns publicly after it was revealed the project would use expensive satellites and rockets.

“The project is an absurd fantasy with neither scientific foundation nor technical feasibility,” Lu Hancheng, a professor at the National University of Defence Technology in Beijing told the state-owned Global Times newspaper.

Byrne agrees, saying clouds would need to be steered in the right direction for the plan to work, which would require an “impossible” change in atmospheric winds.

“It’s almost too huge a problem to even think about … in my view, there’s no realistic chance that this is going to be successful,” he said.

“Directing [water vapour] — that is an incredibly huge task.”

A moon, which replaces the globe in a light globe, hangs over Chengdu's cityscape.
PHOTO: Chinese scientists plan to send three artificial moons into space in the next four years. (ABC News: Graphic by Jarrod Fankhauser)

Likewise, questions remain over how the rockets will be used — a “project insider” told the Global Times they would only be used to monitor water vapour, while others have stated that they would be used to redirect it.

It wouldn’t be the first time China turned to rockets to actively alter weather behaviour.

During the 2008 Beijing Olympics, Chinese state media reported it averted a downpour during the opening ceremony by firing 1,110 rockets into the sky to disturb a rain belt and trigger premature showers before it reached the stadium.

It’s believed the rockets contained cloud-condensation nuclei — particles in the air composed of dust, salt or bacteria which are crucial to create water vapour and cause rain.

The process is called cloud-seeding, but Byrne said even this emerging area of science is still in the early development stages.

“The cloud-seeding experiments that have been done already are incredibly small scale, really local … and even those haven’t been successful,” he said.

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