Why more countries are paying attention to climate modification

Countries around the world are increasingly turning to decades-old weather modification techniques as part of their efforts to control when and where it rains.

In addition to the United States and China, which boast the world’s largest weather modification programs, France, Russia, India and Saudi Arabia also join the growing list of countries that have experimented with cloud seeding.

For many, the embrace of rainmaking projects stems from the need to increase water supplies as global demand continues to rise amid the climate crisis.

Other companies are using cloud seeding to disperse fog at airports, combat air pollution, reduce hail damage, and even manipulate the weather for major events such as the 2008 Summer Olympics in Beijing.

Cloud seeding aims to improve the ability of clouds to produce rain or snow by introducing small particles (usually silver iodide). This process is limited in both area and duration, and is estimated to increase local precipitation by 5% to 15% over time.

However, this concept is not without controversy. Since they were first conducted in the 1940s, cloud seeding experiments have raised concerns about potential environmental and ecological risks and heightened security tensions in the region, with countries accusing each other of stealing rain.

Augustus Dorico, CEO of California-based cloud seeding company Rainmaker, said there are two dynamics at play that seem to be rekindling public interest in the technology, not just in the U.S. but around the world.

“One is really just the situation. Many of these countries and regions are struggling with increasing volatility in climate, precipitation patterns, and water supply, and that’s forcing them to be more creative than they have been in the past,” Dorico told CNBC by phone.

“Secondly, I think this is the real meat and potatoes of why Rainmaker was started, because in the last few years there have been fundamental advances in how we measure and attribute crowd-seeding effects.”

Drico said that despite an 80-year tradition, interest in cloud seeding “really dipped” in the 1970s and 1980s because it was difficult to accurately measure how much precipitation could be gained by implementing cloud seeding.

Recent technology improvements have made it possible to verify the success of these deployments in real time, Dorico said.

The company, which says it wants to stop the drying of the American West, has grown rapidly in recent months, going from just 19 employees at the start of 2025 to 120 today, a trend that appears to highlight growing interest in cloud seeding.

But despite the name, Dorico said his company’s cloud-seeding project is primarily designed to produce snow.

“It turns out we got the name of the company wrong. ‘Snowmaker’ probably would have been more appropriate. That doesn’t sound very good for the value,” Dorico said.

He added: “I think the most important thing for rainmakers to do this season is to create clear evidence of artificial snow. And because we do it so often, there’s no question it’s a viable and scalable technology.”

Other US-based cloud seeding companies include North Dakota’s Weather Modification Inc. and Utah’s North American Weather Consultants, although some US states, such as Florida and Tennessee, have banned weather modification activities.

Frank McDonough, a research scientist at the Nevada-based Desert Research Institute (DRI), says there are two main reasons why so many countries are adopting cloud-seeding strategies.

First, the scientific research and validation efforts that have been conducted on cloud seeding projects around the world over the past several decades have “provided sufficient data and cost-benefit analysis for stakeholders to use this tool with confidence,” McDonough told CNBC via email.

“Another concept behind why more countries are adopting cloud seeding technology is that it is one of the only options to enhance increasingly stressed local water resources or reduce regional air pollution by harnessing the Earth’s natural atmospheric system as a viable water source,” McDonough said.

Most other technologies rely on water resources drawn directly from a basin’s groundwater surface, McDonough said, citing ski resorts’ use of stored water to run winter snowmaking equipment as an example.

“Cloud seeding can actually add new water resources to the system. Stakeholders will continue to fund these projects because there will be additional resources that can be put into the ‘watershed bank’ for next year’s snowmaking needs,” he added.

In terms of national-level support, China reportedly provided $2 billion in support for weather modification programs from 2014 to 2021, and Saudi Arabia spent $256 million in support for the first year of its regional cloud seeding program in 2022.

Iranian authorities reportedly sprayed clouds in the Urmiyah Lake basin late last year with chemicals to increase rainfall in response to the worst drought in decades.

However, such projects are not always successful. A team from the Indian Institute of Technology (IIT) Kanpur, in collaboration with the Delhi government, recently reported mixed results from a cloud seeding trial to tackle air pollution in the Indian capital.

IIT said in a statement at the time that the attempt was “not completely successful” due to lack of moisture in the air, before adding that particulate matter had visibly reduced after the experiment.

Diana Francis, director of the Environmental and Geophysical Sciences Laboratory at Abu Dhabi’s Khalifa University, said cloud seeding could lead to a “moderate increase” in precipitation under the right conditions.

“But it is incremental rather than transformational and is most effective as part of a broader water and air quality strategy,” Francis told CNBC via email.

Francis noted that cloud-seeding operations can typically cost between $1 and $10 per hectare meter of additional water, which, while still highly variable, would be much cheaper than desalination.

Francis says there are other important caveats to consider, including strong dependence on cloud microphysics (given that cloud seeding only works with existing clouds), attribution issues, and potential geopolitical and legal issues regarding downwind impacts.

The World Meteorological Organization said studies have shown that silver iodide cloud seeding projects to date have not had a significant impact on human health or the environment, but further research is needed to assess downwind impacts.

The United Nations Meteorological Agency also acknowledges that significant challenges continue to exist in public, social and local acceptance of rainmaking activities.