China is building the foundations of what will become the largest artificial rain experiment in history, in an attempt to induce extra rainfall over the Tibetan Plateau.

The project will see tens of thousands of fuel-burning chambers installed across the Tibetan mountains, with a view to boosting rainfall in the region by up to 10 billion cubic metres annually, according to reports.

The plan, which is an extension of a project called Tianhe or 'Sky River' developed by researchers in 2016 at China's Tsinghua university, is hoped to bring extra rain to a massive area spanning some 1.6 million square kilometres (almost 620,000 square miles).

For a bit of context, that's larger than Alaska, and about three times the size of Spain, according to the South China Morning Post (SCMP), and this immense scope means the extra rainfall expected will also be voluminous if the plan succeeds, equivalent to roughly 7 percent of China's annual water consumption.

"[Modifying the weather in Tibet] is a critical innovation to solve China's water shortage problem," said Lei Fanpei, president of the state-owned China Aerospace Science and Technology Corporation, which is developing the project.

"It will make an important contribution not only to China's development and world prosperity, but also the well being of the entire human race."

While it sounds like something out of science fiction, this form of weather modification, called cloud seeding, is something scientists have been trying to pull off for decades now, and China is more deeply invested in the concept than anywhere else in the world.

In the Tibetan project, the burning chambers will produce silver iodide particles that will be carried into the atmosphere by the wind, where they are expected to seed moisture clouds capable of producing rain and snow.

"[So far,] more than 500 burners have been deployed on alpine slopes in Tibet, Xinjiang, and other areas for experimental use," one researcher working on the project told SCMP.

"The data we have collected show very promising results."

But not everybody is convinced of China's plans of creating artificial rainfall over such a wide area, especially because there's still a lot we don't know about how cloud seeding – which is usually initiated by more localised chemical agents released into the atmosphere by planes – affects broader weather patterns.

"Such weather modification does not 'produce' rain as such," geoengineering researcher Janos Pasztor from the Carnegie Climate Geoengineering Governance Initiative (C2G2) told Gizmodo.

"Rather, it makes rain happen somewhere, which means that it will not happen somewhere else. This immediately means that ecosystems and people living somewhere else where it would have rained will no longer get this rain."

If that's correct, the potential effects of China's Sky River could mean whole cloud systems covering an area the size of Alaska might be diverted to boost rainfall over the Tibetan Plateau.

It's not known when the project will be completed, but given how huge, and hugely controversial, this plan could become, we doubt we've heard the last of this.