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Vol. 53-2 Recent Publication

August 11, 2023

Recent Publication

Robert “Bo” Abrams & Alexis Clark, Weather Modification Past and Prologue, 37 Nat. Res. & Env’t 21 (2022)

Who owns the clouds? Although the United States began experimenting with weather modification techniques to enhance precipitation as early as the 1940s,[1] the topic has received limited attention from regulatory bodies.[2] “Weather modification” is “the deliberate and mindful effort” to control the weather for societal purposes.[3] For example, the U.S. uses weather modification techniques to “enhance precipitation, protect crops from hail damage, clear fog at airports, . . . reduce air pollution[,]” and even potentially alter the trajectory of major hurricanes.[4]

As climate change continues to strain water supplies and increase the severity of drought and fire seasons,[5] precipitation enhancement may prove to be a vital part of water management and habitat rehabilitation.[6] In the recent article, Weather Modification Past and Prologue, Robert “Bo” Abrams and Alexis Clark analyze the history of weather modification in the U.S. and summarize scientific and legal barriers to the widespread use of this tool to combat climate change.[7] Abrams and Clark ultimately call for federal support of weather modification activities, particularly a precipitation enhancement technique called “cloud seeding.”[8]

The Science Behind Cloud Seeding & Historic Use of Precipitation Enhancement

“Cloud seeding” is a technique used to “promot[e] the condensation of water vapor in clouds around a nucleating agent—or seed—into either ice crystals” or water droplets, “which then become heavy enough to fall to the ground as precipitation.”[9] The most common “seed” is silver iodine, which is released into clouds using drones, special aircraft, or ground generators.[10] This method of weather modification was discovered in the 1940s by researchers for General Electric and the Office of Naval Research while attempting to deice aircraft wings.[11]

Water-stressed states—including Texas—have used cloud seeding since the 1950s.[12] Atmospheric modeling was then in its infancy, which limited scientists’ ability to prove the technique’s effectiveness.[13] This resulted in a “lack of a coordinated national effort to link understanding of atmospheric science to the processes behind weather modification.”[14] Abrams and Clark admitted that—even today—the scientific community is divided in its support for cloud-seeding technology, with some questioning its efficacy.[15] One major concern is that drought conditions can be so severe that “no amount of seeding can force water from the sky.”[16]

Still, some seeding programs have shown potential.[17] For example, studies show that existing seeding programs in the Colorado River Basin could be expanded to produce a 10–15% increase in snowpack.[18] For context, this would generate an additional 1 million acre-feet of water per year, or “enough water to supply between 1 and 3.5 million households each year.”[19] Cloud seeding is also more cost-effective than other methods of developing water.[20] For example, at $5–$30 per acre-foot, seeding is up to 100 times cheaper than desalination, which can cost as much as $3,000 per acre-foot.[21] Given its cost-efficiency and potential for success, Abrams and Clark argue that “[t]he addition of a cloud-seeding program to a water management portfolio seems like a no-brainer.”[22]

Early Legal Framework

Although federal agencies have been assigned to research and evaluate weather modification activities since the 1950s, the federal government’s approach has been relatively hands-off.[23] It was not until several decades later that Congress pursued “concrete federal action on weather modification” through the Weather Modification Policy Act of 1976 (WMPA).[24] The WMPA mandated that the Secretary of Commerce create a national policy on weather modification and assess the “economic, social, environmental, and legal impact . . . of a national program for managing weather modification.”[25] The WMPA also sought to: (1) “develop model codes and agreements to ensure peaceful regulation of domestic and international weather modification activities”; (2) “set minimum reporting standards for weather modifiers”; (3) provide additional funding for research and development; and (4) “creat[e] a congressionally appointed advisory board to provide further recommendations.”[26]

In 1978, the advisory board recommended that the federal government strengthen regulation of weather modification activities beyond mandatory requirements under the National Environmental Policy Act and dedicate funding to assess the long-term effects of weather modification.[27] The board recommended mandatory reporting and evaluation of silver iodide concentrations over time, changes in streamflow, migration of ecosystems due to changed annual precipitation patterns, changes in water quality, and invasive species.[28] Finally, the report encouraged Congress to immediately promulgate a federal licensing program, operating standards for weather modifiers, and an “express affirmation of liability for weather modifications under the Federal Tort Claims Act.”[29]

Current Legal Status of Weather Modification & Use of Cloud Seeding

Unfortunately, the federal government has not passed new legislation on weather modification since the 1970s, and the WMPA has largely laid dormant.[30] Abrams and Clark theorize that “the overselling of the potential impact and scope of weather modification in the 1950s and 1960s undercut interest in continued federal funding for research and development.”[31] They also note that the “militarization” of weather by the U.S. during the Vietnam War negatively affected public perception of weather modification and stagnated research and policy.[32]

Even so, a handful of states and private parties have consistently funded small-scale precipitation enhancement projects.[33] While eighteen states have current weather modification laws, half of these states only allow weather modification activities during emergencies or in a limited capacity.[34] All state laws on weather modification include mandatory reporting requirements, and most also include licensing, permitting, and public notice requirements.[35] The “teeth” behind weather modification laws vary from state to state, resulting in “an inconsistent patchwork of regulations for activities that have potential transboundary effects.”[36]

Abrams and Clark note that cloud-seeding activities also trigger lawsuits over liability damages and water rights—essentially litigating who owns the clouds.[37] Plaintiffs seeking injunctions against weather modifiers typically do not prevail in court, either because damages would adequately compensate them for any injuries, or “[t]he current lack of replicable and predictable scientific results for activities leaves the plaintiff without an essential element to their cause of action,” especially in states where strict liability claims are prohibited.[38]

In seven states, water from cloud-seeding activities is treated like natural precipitation allocated by the state’s prior appropriation laws.[39] Only four cases have addressed who owns the clouds.[40] The New York Supreme Court held that country club owners could not enjoin nearby weather modification activities that had the potential to flood the country club.[41] The country club owners’ claim had no factual basis to prove an injury, and there was no evidence that the potential injury would outweigh the possible public benefits of weather modification.[42] However, in Texas, ranchers successfully obtained an injunction against a weather modification organization’s performance of hail suppression activities, which affected the plaintiff’s land.[43] In another Texas case, the Texas Court of Civil Appeals affirmed that a landowner was entitled to protection from the impact of hail suppression activities.[44] A Pennsylvania district court similarly held that precipitation is “common property held by all,” but the right to precipitation that falls on your land is “not unqualified” and “can be regulated by the state.”[45]

The Future of Weather Modification

Abrams and Clark ultimately conclude that weather modification activities such as cloud seeding are a “vital part of the toolbox for navigating climate change and avoiding past mistakes.”[46] Echoing the recommendation of the advisory board in the late 1970s, Abrams and Clark call for a more hands-on approach from the federal government, including: “(1) recordkeeping requirements, reporting, and public transparency; (2) establishment of federal minima, such as environmental assessment and adoption of industry standards; and (3) adequate funding for research and development.”[47]

This article provides a helpful analysis of the potential of weather modification to combat the effects of climate change. In light of southwest Texas’ worst drought in at least 1,200 years,[48] the topic is particularly timely. Although the article doesn’t suggest a particular blueprint for a new regulatory framework, it re-sparks the conversation over who owns the clouds.


Josh Katz is a partner at Bickerstaff Heath Delgado Acosta LLP and represents public and private entities before agencies and in state and federal court in the areas of environmental law, municipal law, water rights, and utilities.

Lauren Alexander is a 3L from Emory, Texas. Lauren joined TELJ during her 2L year and currently serves on the TELJ Board as an Article and Notes Editor. Lauren is excited to start a post-graduate position at Perales, Allmon & Ice, PC in Austin, where she will represent landowners, nonprofits, and other protestants in environmental matters.


[1]      Robert “Bo” Abrams & Alexis Clark, Weather Modification Past and Prologue, 37 Nat. Res. & Env’t. 21, 21 (2022).

[2]      Id. at 24–25.

[3]      Weather Modification Advisory Bd., Dep’t of Com., The Management of Weather Resources Volume I: Proposals for a National Policy and Program 17 (1978).

[4]      Abrams & Clark, supra note 1, at 21, 23.

[5]      Id. at 24–25. “Ongoing drought conditions in the western U.S. make the beginning of this century the worst period since 800 C.E., with at least 19% of this period attributable to anthropogenically induced climate change from 2000-2021, turning what is already a severe drought into a megadrought predicted to continue for several more years.” Id. at 23.

[6]      See generally Abrams & Clark, supra note 1.

[7]      See id. at 23.

[8]      Id.

[9]      Id. at 21.

[10]     Id.

[11]     Id.

[12]     Abrams & Clark, supra note 1, at 22.

[13]     Id. at 23.

[14]     Id. at 21.

[15]     Id.

[16]     Id. at 22.

[17]     See id. at 23.

[18]     Abrams & Clark, supra note 1, at 22.

[19]     Id.

[20]     Id. at 22–23.

[21]     Id. at 23.

[22]     Id.

[23]     Id. at 21.

[24]     Abrams & Clark, supra note 1, at 22.; Weather Modification Policy Act of 1976, Pub. L. No. 94-490.

[25]     Abrams & Clark, supra note 1, at 22; Weather Modification Policy Act § 2(b)(5).

[26]     Abrams & Clark, supra note 1, at 22.

[27]     Id. (citing Thomas F. Malone & Harlan Cleveland, The Management of Weather Resources—Proposals for a National Policy and Program, 59 Bull. Am. Meteorological Soc’y 1266, 1271 (1978)).

[28]     Id.

[29]     Id. (citing Malone & Cleveland, supra note 27, at 1271–72).

[30]     Id. at 23.

[31]     Id.

[32]     Abrams & Clark, supra note 1, at 23.

[33]     Id.

[34]     Id. at 23–24.

[35]     Id.

[36]     Id.

[37]     Id. at 24.

[38]     Abrams & Clark, supra note 1, at 24.

[39]     Id. at 25.

[40]     Id. at 24–25.

[41]     Id. at 25 (citing Slutsky v. New York, 197 Misc. 730 (N.Y. Sup. Ct. 1950)).

[42]     Id.

[43]     Id. (citing Sw. Weather Rsch., Inc. v. Jones, 160 Tex. 104 (1959)).

[44]     Abrams & Clark, supra note 1, at 25 (citing Sw. Weather Rsch., Inc. v. Duncan, 319 S.W.2d 940 (Tex. Civ. App. 1958)).

[45]     Id. (citing Pa. Nat. Weather Ass’n v. Blue Ridge Weather Modification Ass’n, 44 Pa. D. & C.2d 749, 759–60 (C.P. Fulton County, Pa. 1968)).

[46]     Id.

[47]     Id.

[48]     Megadrought In Parts Of Texas, American West Worsens To Driest In 1,200 Years, CBS DFW (Feb. 15, 2022, 5:41 AM),