Citing a lack of evidence that it works, the Wyoming House slashed all $1.1 million of funding for the state’s cloud-seeding program on Monday.
The money and program stipulations were included within a $114 million omnibus water construction bill but were removed by a large majority of the members in the House. The decision isn’t final until the Legislature approves a final supplemental budget.
A similar cut was proposed in the Wyoming Senate in 2023 but rejected.
Cloud seeding is seen by its supporters as a potential benefit for Cowboy State farmers, kayakers and other water enthusiasts as a way to increase statewide and local water reserves
To Seed Or Not To Seed
State Rep. Mike Schmid, R - La Barge, proposed cutting cloud seeding, arguing there’s a lack of evidence that it works while also raising questions as to whether it may be detrimental to the environment. He urged his fellow lawmakers to pause the program until it can be studied more.
“I don’t know how they can tell us this is a positive effect when they don’t really know what Mother Nature would have done,” Schmid said.
Schmid said two of the biggest concerns for his constituents are the shrinking glaciers and bighorn sheep populations in western Wyoming.
Cloud seeding uses silver iodide to enhance ice crystal production within clouds. When seeding is done from a plane, the pilot ignites one flare at a time, shooting the compound into the cloud. The iodide causes water droplets in the clouds to form ice crystals that become heavier and fall faster, which sometimes initiates snowfall.
Schmid attempted to bridge a possible connection between Wyoming’s cloud seeding program and declines in wildlife populations due to the “unknown long term effects” of persistent exposure to silver iodide.
He also pointed out that adult bighorn sheep are extremely susceptible to pneumonia and suffer from reduced immune systems due to chemicals like iodide.
“Could this be it? I don’t know,” he said. “Because I can’t find any reports on the long term effects of this.”
Rep. Bob Nicholas, R-Cheyenne, disagreed, saying bighorn sheep populations disappeared around a residence he owns in Lander multiple times and there wasn’t any cloud seeding performed nearby or silver iodide identified in their demise.
“Do we need to know more about it? Absolutely,” Nicholas said. “But you don’t pause it, unless you have to, because you have data to prove it, and we don’t have that.”
Schmid also expressed concern that iodide piling up on glaciers could cause the ice and snow to melt quicker because it will darken the surface and thus draw more heat to it.
What’s It For?
By augmenting mountain snowpacks, supporters hope the seeding will counteract the effects of climate change and help quench the thirst of drought-stricken areas throughout the state.
The state performs its cloud seeding through airborne and ground-based cloud seeding deployments run by the Wyoming Water Development Office.
Wyoming’s cloud seeding operations formally began in 2014 on the heels of the Wyoming Weather Modification Pilot Project program, which had run for nine years prior, but relied solely on ground-based cloud seeding generators.
What started as a project focused in the Wind River Mountains has since expanded to other parts of Wyoming. Airborne seeding, which involves shooting silver iodide out of flares strapped to the wings of an airplane, was added in 2018.
In late 2021, the Wyoming Water Development Commission advanced a proposal by the state Water Development Office to add two ground-based generators in the Sierra Madre mountains and add two weeks to the seeding season.
The cost of these additions was $316,000. There also are 10 remote-controlled, ground-based generators located on the western and southern aspects of the Wind River Range.
A 2014 research study analyzing the results of Wyoming’s pilot program showed cloud seeding causing a 5% to 15% increase in the “efficiency” of mountain snow.
Newer calculations estimate an additional annual water flow from 12,000 to 49,000 acre-feet as a result of seeding. A 2017-20 study in Idaho shows that three of 18 cloud-seeding events there were successful, according to the National Center for Atmospheric Research and the University Corporation for Atmospheric Research.
Questionable Data
Schmid argued that the studies performed amount to “opinions in support of the project.”
Rep. Laurie Bratten, R-Sheridan, a former biologist, agreed, saying she would’ve voted to support the program until she found a lack of data showing that it's working.
“I assumed we would have some data to show for it,” she said. “We just don’t. Vote defund.”
In 2003, the National Academy of Sciences produced a study reporting a high degree of uncertainty regarding the efficacy of cloud seeding. According to the Bulletin of the Atomic Scientists, since that time numerous studies have been conducted, but the evidence remains inconclusive on cloud seeding.
A recent synthesis by the World Meteorological Organization concluded that increased precipitation ranged between 0%- 20%, with the upper range representing conditions under which clouds were already highly likely to form precipitation naturally.
It is also widely acknowledged that cloud seeding is least likely to be effective during drought conditions, as clouds do not have moisture to release.
A cost-sharing agreement in the Colorado River Basin was finalized in 2018 for ground-based efforts to combat shrinking water levels, which extends through fall 2026. Under the agreement, Wyoming pays 37% and the “other Colorado River Basin water users or other interested parties” are on the hook for the remaining 63%.
Rep. J.T. Larson, R-Rock Springs, warned that bailing on this agreement “sends a very bad signal to the lower Basin states.”
But even a few Democrats spoke against the program on Monday like Rep. Mike Yin, D-Jackson, who expressed doubt that Wyoming is getting its bang for the buck by running it even though he believes it does work on a certain level.
“I don’t know if it’s worth it, Yin said. “It doesn’t help a lot of the state. I’ve never thought the juice was worth the squeeze.”
Yin did say he would support continuing Wyoming’s ground-deployed cloud seeding at a cost of $322,143.
Rep. Karlee Provenza, D-Laramie, agreed, but also said claims Schmid made that the iodide used for cloud seeding was harming elk populations is false. She and Nicholas pointed out that Wyoming Game and Fish has never identified the presence of iodide leading to widespread bighorn sheep deaths.
“Our bighorn sheep are not dying because of cloud seeding,” Provenza said.
Leo Wolfson can be reached at leo@cowboystatedaily.com.
