A few days after a flash flood in Texas killed at least 135 people, Florida Attorney General James Uthmeier promoted a new law he says will help the state avoid the same scenario.
He wasn’t talking about installing sirens or improving emergency warning systems. His message was about prohibiting weather modification.
In a July 14 letterUthmeier reminded public-use airports to comply with a new law that prohibits weather modification in the state. Airports need to submit monthly reports on geoengineering and weather modification activities starting in October, or potentially lose state funding, he wrote.
“From farmlands to our waterways, to the very air we breathe—Floridians’ health is under attack from toxic particulates being sprayed into our atmosphere, polluting our water, contaminating agriculture, and destroying human health,” Uthmeier wrote.
Some people think of weather modification and geoengineering as nefarious government activities, and blame them for natural disasters such as Hurricane Helene. Weather modification involves activities that artificially change the atmosphere’s composition, behavior or dynamics. Geoengineering involves efforts that attempt to cool the Earth.
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In his letter, Uthmeier invoked debunked claims that cloud seeding caused the July 4 Texas flash floods.
“I can’t help but notice the possibility that weather modification could have played a role in this tragedy,” he said, referring to a company’s cloud-seeding operations more than 24 hours before the flash flood. “Florida’s new law seeks to prevent something like that from ever happening.”
Meteorologists told PolitiFact the cloud-seeding could not have caused a storm big enough to cause a deadly flood.
Experts in atmospheric science and aerospace engineering said weather modification experiments don’t pose a threat to Florida.
If there are toxic particulates circulating in the Floridian air, weather modification is not to blame. Department of Environmental Protection records show no one has applied for or received a weather modification license since it became a requirement in 1957.
“The Florida law is potentially getting ahead of a future issue more than its addressing the effect of activities happening right now,” said Richard Lind, University of Florida associate professor who specializes in aerospace engineering.
Still, the Tampa International Airport and the St. Pete-Clearwater International Airport are gearing up to comply with the requirements ahead of the Oct. 1 deadline, the Tampa Bay Times reported.
No one has ever applied for weather modification licenses, state says
Florida SB 56 repealed the law requiring people and entities to get a license before conducting geoengineering or weather modification activity, implementing a total ban instead.
The law bans the release of chemicals or apparatus “for the express purpose of affecting the temperature, weather, climate, or intensity of sunlight.”
At this point, the law doesn’t have an immediate effect, given the lack of weather modification activities in the state. The Florida Department of Environmental Protection told PolitiFact it “has never received any applications for weather modification licenses, permits or authorizations” and “has never issued any such licenses, permits or authorizations since the original statute was enacted in 1957 or under the new statute.”
In 1957, citrus growers in three counties did cloud seeding, but discontinued the project, the Tampa Bay Times reported.
We asked whether the department has received reports of unlicensed weather modification activities, but did not get an answer. We also contacted Uthmeier’s office but did not hear back.
Under Uthmeier’s X post, where he shared his letter, people shared images of white streaks in the sky, which are associated with the “chemtrails” conspiracy theory. The white streaks are contrails or condensation trails produced by aircraft engine exhaust, not evidence of a secret large-scale atmospheric program.
One proposed geoengineering method is marine cloud brighteningwhich involves injecting salt spray into shallow marine clouds, letting them better reflect sunlight. This leads to cooler water below. Florida is not ideal for this approach, however, because its marine clouds rain out quickly, said Paquita Zuidema, the University of Miami’s Department of Atmospheric Sciences chair.
One kind of weather modification being done in nine states is cloud seeding, which involves adding silver iodide to clouds to increase rain or suppress hail. Research on the impact and effectiveness of cloud seeding is limited, according to the U.S. Government Accountability Office.
“This type of weather modification is done at ski resorts and some arid regions out west,” Zuidema said. “Floridian clouds don’t have so much super-cooled water and perhaps our need for rain is not so high.”
In the 1960s, the federal government’s “Project Stormfury” studied whether technology could change hurricane intensity. The project had mixed results; it was difficult to assess whether hurricanes changed because of the experiment or their natural behavior. The government has not tried weather modification since.
Companies that do weather modification activities submit reports to the National Oceanic and Atmospheric Administration. Many of the activities reported to NOAA in 2024 have to do with rainfall enhancement or increasing precipitation. Contrary to claims and conspiracy theories, there’s no evidence that these have caused hurricanes, floods or other natural disasters.
None of these activities were in Florida.
