30-07-2025
Blame it on the rainmaker
TWO days before the Guadalupe River swelled into a deadly Fourth of July flood in Kerr County, Texas, engineers with a California-based company called Rainmaker took off in a small aircraft about 160km away and dispersed 70g of silver iodide into a cloud.
Their goal? To make it rain – part of a weather modification practice known as cloud seeding, which uses chemical compounds to encourage water droplets in clouds to coalesce and fall as rain.
But in the aftermath of the flood, which killed at least 135 people – including dozens of children – a storm of a different kind erupted online.
'I NEED SOMEONE TO LOOK INTO WHO WAS RESPONSIBLE FOR THIS. WHEN WAS THE LAST CLOUD SEEDING?' wrote Pete Chambers, a former US special forces commander and far-right activist, on X.
His post received 3.1 million views.
Others followed suit.
Former Trump national security adviser Michael Flynn, in a repost, did not mince words when he slammed Chambers' claim.
Scientists were quick to refute the allegations.
'It's very clear they have nothing to do with it,' said Daniel Swain, a climate scientist at the University of California, in a briefing after the flood.
Rainmaker also denied any connection. The storm, fuelled by tropical moisture, dropped as much as 10cm of rain per hour, with river levels in some areas rising nine metres in under 45 minutes.
Rescue team (right) moves along the Guadalupe River in search of flood victims near a damaged building. — AFP
But for conspiracy theorists who have long claimed that governments manipulate the weather, the narrative was already seeded.
Soon after, Republican Representative Marjorie Taylor Greene proposed a Bill to make all forms of weather modification – including cloud seeding – a felony.
'This is not normal,' she posted. 'No person, company, entity or government should ever be allowed to modify our weather by any means possible!'
In response to growing speculation, the US Environmental Protection Agency (EPA) launched two new websites aimed at addressing public concerns about weather modification, geoengineering and aircraft contrails.
'To anyone who's ever looked up to the streaks in the sky and asked, 'what the heck is going on?' – we've tried to answer all your questions,' EPA administrator Lee Zeldin said in a video launch.
The agency distinguishes between geoengineering – which aims to influence global climate – and cloud seeding, which is localised and shortlived.
Cloud seeding itself isn't new. It was pioneered in the US nearly 80 years ago by scientists, including Bernard Vonnegut, brother of novelist Kurt Vonnegut.
Since then, it's been used to supplement rainfall in areas suffering drought, though its effectiveness has always been modest.
Rainmaker's flight on July 2 took place near Runge, 200km southeast of the flood zone.
The team flew to an altitude of 500m and dispersed 70g of silver iodide – 'less than a handful of Skittles', said company founder Augustus Doricko.
The yellow compound helps turn water droplets in clouds into ice crystals, prompting precipitation.
Soon after the flight, Rainmaker's meteorologists noticed an incoming moisture front and suspended operations.
By 1am the next day, the National Weather Service had issued its first flash flood warning for Kerr County.
Doricko said the scale of the flood dwarfed anything cloud seeding could cause.
'The best seeding operations produce maybe 100 million gallons of rain,' he said. 'That flood delivered over a trillion gallons.'
Swain agreed. 'Cloud seeding doesn't create clouds,' he said. 'It enhances what's already there, and its effects last minutes – maybe an hour.'
At best, Swain noted, seeding can boost rainfall by 10% to 15%, and often not even that.
'In some cases, it's difficult to prove cloud seeding does anything at all.'
Andrew Dessler, a professor of atmospheric sciences at Texas A&M University, went further.
'There's no physical way that cloud seeding could've made that storm,' he said.
The event was driven by extreme moisture from a tropical disturbance in the Gulf of Mexico.
Dessler called the backlash against Rainmaker a distraction from the real problem – climate change driven by carbon emissions.
'There is a conspiracy to change the climate,' he said. 'It's fossil fuel interests and the system that supports them.'
Despite such doubts, cloud seeding continues to attract interest.
Rainmaker has worked with the Utah and Colorado departments of natural resources, the Oregon Department of Agriculture and several California municipalities.
San Luis Obispo County began seeding in 2019 after years of drought and low water levels in its Lopez Lake reservoir.
'We added about 1,200 acre-feet per year,' said David Spiegel, the county's supervising engineer. (One acre-foot is around 1.23 million litres)
The best year yielded roughly three million cubic metres of water – modest, but cost-effective at around US$300 per acre-foot, far below the US$1,500 cost of imported water.
While results were mixed due to limited storms during the drought, Spiegel considers it a viable option – especially if future legislation bans it.
'It would be a setback,' he said. 'We're always looking for ways to increase our water supply.'
California isn't investing in state-run programmes but tracks such activities.
As of October, at least 16 cloud-seeding projects were active across various counties.
With climate change straining water resources and negotiations over the shrinking Colorado River ongoing, some see weather modification as part of the future.
A 2021 National Academies of Sciences report said geoengineering, while controversial, might serve as a last resort – a kind of planetary airbag.
But it cautioned that such methods must not be seen as a substitute for cutting greenhouse gas emissions.
Dessler likened the current political debate over cloud seeding and geoengineering to ideological posturing.
'It makes no sense,' he said. 'This isn't about facts. It's about worldview.' — Los Angeles Times
