Actual Weather Experts Explain What ‘Weather Modification’ Does, Minus The Conspiracy Theories

In the wake of the devastating floods in Texas, Rep. Marjorie Taylor Greene announced new legislation aimed at an unusual target: weather modification.

“I am introducing a bill that prohibits the injection, release, or dispersion of chemicals or substances into the atmosphere for the express purpose of altering weather, temperature, climate, or sunlight intensity,” the Georgia Republican posted on X, formerly Twitter. “It will be a felony offense. I have been researching weather modification and working with the legislative counsel for months writing this bill.”

She said that the legislation will be similar to Florida’s Senate Bill 56 and added, “We must end the dangerous and deadly practice of weather modification and geoengineering.”

But what exactly is “weather modification”? Is it actually happening? And is it deadly? HuffPost asked experts to explain the term, as well as the most common example ― “cloud seeding” ― and what you should know about it.

“Weather modification simply means trying to change or influence the weather in some way,” Frank Lombardo, a certified consulting meteorologist and CEO of WeatherWorks, told HuffPost. “That could be trying to increase rain or snow, reduce hail or lessen the intensity of a weather event. It’s really just a way to nudge the atmosphere in a certain direction ― with varying results.”

As science advances and climate change leads to more extreme and unpredictable weather, there’s been increased interest in weather modification.

“Weather modification intentionally alters the weather using technology,” said Katja Friedrich, a professor and chair of the department of atmospheric and oceanic sciences at the University of Colorado Boulder. “This includes cloud seeding, hail suppression, hurricane weakening, fog suppression.”

The idea of being able to lessen devastating storms or put an end to severe droughts is certainly tempting, but we aren’t actually able to carry out these kinds of weather modifications effectively at a large scale. And even if that changes, there are concerns about unintended consequences on ecosystems, international cooperation, ethical distribution of resources and more.

While large-scale weather modification doesn’t yet exist, cloud seeding is the most widely studied and applied method.

“Cloud seeding is when we add tiny particles ― like silver iodide or dry ice ― into clouds,” Lombardo said. “These particles help form more water droplets, which can lead to more rain or snow.”

You’ll mostly find this happening regionally, in places like the Western U.S., China and the United Arab Emirates for the purposes of drought relief and/or snow generation in specific areas. Basically, special planes or generators on the ground release the seeding agents to encourage water droplets to form and fall.

Most clouds do not need to be seeded, Friedrich said, as precipitating clouds are generally good at doing this naturally.

“The goal is usually to increase precipitation, but some people also talk about using cloud seeding to calm storms or break up heavy rain ― though that’s mostly theoretical and not well proven,” Lombardo noted.

“There are so many misconceptions around cloud seeding, and I am always honored to see how much confidence people have in science,” Friedrich said. “Unfortunately, we showed in our studies on orographic wintertime cloud seeding that we can produce snow through cloud seeding, but it is really not that much.”

Indeed, cloud seeding has only shown modest success in increasing precipitation, with studies indicating about 5-15% or even 20% jumps under optimal conditions. It’s also difficult to fully gauge effectiveness, as weather is dynamic, and many factors can play into changes in precipitation.

“Its usefulness is extremely limited,” said Clifford Mass, a professor of atmospheric and climate sciences at the University of Washington. “Some people are making money doing cloud seeding, but the benefit is extremely small. Probably the most valuable use of it is with supercooled fog in Arctic areas. The ability to modify precipitation is marginal at best.”

Cloud seeding also only works if there are already existing clouds. You cannot use cloud seeding to create a single cloud out of thin air, and its impact on precipitation is not enough to form a large storm even if there are many existing clouds filled with moisture.

“If we were that good at cloud seeding, we would have solved the water crisis in the Western U.S. or any other arid place in the world,” Friedrich said. “Nature is powerful and often very efficient in producing large amounts of precipitation.”

She added that other forms of weather modification aren’t anywhere near as common as cloud seeding ― if they’re even possible at this point.

“The research around hurricane and hail suppression has shown that we are not able to modify anything significantly,” Friedrich said. “I don’t know of any hurricane seeding activities. Hail suppression is still being done, but there is very little scientific evidence that we can alter hailstone sizes in thunderstorms. I also haven’t seen much around fog suppression.”

Lombardo wanted to clear up to another misconception around cloud seeding.

“Some folks think if you seed clouds in one area, you ‘steal’ the rain from nearby areas,” he said. “But there’s no real evidence to support that. Cloud seeding might help in one region, but it doesn’t cancel out rain somewhere else.”

The many misconceptions and general lack of public understanding around weather modification have given rise to many conspiracy theories around weather modification. In the aftermath of devastating events like the floods in Texas, these theories tend to get a bigger spotlight.

“When a disaster hits ― like a big flood or hurricane ― people naturally look for someone or something to blame,” Lombardo said. “Is it cloud seeding? Climate change? Bad planning? Politics?”

He noted that Texas has a long history with cloud seeding, particularly in drier parts of the state, so it could feel like a convenient answer to the flooding. Social media posts about the government or private entities “engineering” disasters offer an easy scapegoat.

“First off, cloud seeding didn’t cause the massive storm that hit Texas on July 4–5,” Lombardo said. “Events like that are driven by much bigger weather patterns, and they’re tough to forecast ― and even more difficult to control. Also, cloud seeding can’t stop hurricanes or weaken them. People have tried, but it hasn’t worked.”

Although Marjorie Taylor Greene didn’t explicitly link her legislative proposal to the flooding in Texas, the timing of her announcement and previous statements following natural disasters certainly fuels the conspiracy theory.

“It’s just complete nonsense,” Mass said of links between weather modification and the Texas flooding. “They think that the U.S. government has a secret program that are creating the clouds in the sky.”

He also compared the frenzy to the debunked conspiracy theory around chemtrails ― which Health and Human Services Secretary Robert F. Kennedy Jr. has also promoted.

As with conspiracy theories before it, the linking of the Texas flooding to cloud seeding tends to say more about human psychology than about science.

“We as human beings want to find answers to our why and who questions,” Friedrich said. “Simply accepting that nature is powerful and hurricanes and flooding can cost lives is harder to believe, because we have to accept it and cannot blame anyone.”