STORAGE NAME: h0477b.SAC
DATE: 4/17/2025
1
FLORIDA HOUSE OF REPRESENTATIVES
BILL ANALYSIS
This bill analysis was prepared by nonpartisan committee staff and does not constitute an official statement of legislative intent.
BILL #: CS/CS/HB 477
TITLE: Geoengineering and Weather Modification
Activities
SPONSOR(S): Steele, Mayfield
COMPANION BILL: CS/CS/SB 56 (Garcia)
LINKED BILLS: None
RELATED BILLS: None
Committee References
Natural Resources & Disasters
17 Y, 0 N, As CS
State Affairs
15 Y, 9 N, As CS
SUMMARY
Effect of the Bill:
The bill prohibits geoengineering and weather modification activities. Specifically, the bill prohibits the injection,
release, or dispersion, by any means, of a chemical, a chemical compound, a substance, or an apparatus into the
atmosphere within the borders of the state for the express purpose of affecting the temperature, weather, climate,
or intensity of sunlight. Any person who violates this prohibition commits a third degree-felony, punishable by up
to five years in prison and a fine up to $200,000.
The bill requires the Department of Environmental Protection (DEP) to establish an e-mail address and an online
form for anyone to report observed violations of this prohibition. DEP must investigate any report that warrants
further review and refer reports to other specified agencies if appropriate.
The bill requires an operator of a publicly owned airport to report to the Department of Transportation (DOT)
monthly on the presence of any aircraft on public property that may be used for geoengineering or weather
modification activities.
The bill repeals all other weather modification statutes, including DEP’s weather modification license program.
Fiscal or Economic Impact:
The bill has an indeterminate negative fiscal impact on DEP related to creating an online form to report suspected
geoengineering and weather modification activities and investigating such reports. DOT and publicly owned
airports may also incur costs related to the reporting requirements for such airports.
JUMP TO SUMMARY ANALYSIS RELEVANT INFORMATION BILL HISTORY
ANALYSIS
EFFECT OF THE BILL:
Geoengineering and Weather Modification
The bill prohibits geoengineering and weather modification activities. Specifically, the bill prohibits the injection,
release, or dispersion, by any means, of a chemical, a chemical compound, a substance, or an apparatus into the
atmosphere within the borders of the state for the express purpose of affecting the temperature, weather, climate,
or intensity of sunlight. (Section 2)
The bill specifies that any person who violates this prohibition commits a third degree-felony, punishable by up to
five years in prison and a fine up to $200,000. If a public or private corporation violates the prohibition, the
officers, directors, or employees of the corporation commit a third-degree felony, punishable by up to five years in
prison and a fine up to $200,000. If the violator is an aircraft operator or controller, the penalty is a third-degree
felony punishable by up to five years in prison and a fine up to $5,000. The bill specifies that each violation is a
separate offense. (Section 2)
JUMP TO SUMMARY ANALYSIS RELEVANT INFORMATION BILL HISTORY
2
The bill requires all moneys collected pursuant to these violations to be deposited in the Air Pollution Control
Trust Fund and used only for purposes of air pollution control. (Section 2)
The bill authorizes any person who observes a geoengineering or weather modification activity conducted in
violation of the above prohibition to report the violation to the Department of Environmental Protection (DEP)
online or by telephone, mail, or e-mail. The bill requires DEP to establish an e-mail address and an online form for
individuals to report observed violations and requires DEP to make the e-mail address and online form publicly
accessible on its website. In addition, the bill requires DEP to establish a method for intake and screening of the
reports and to investigate any report that warrants further review to determine whether violations have occurred.
DEP must refer reports of observed violations to the Department of Health or the Division of Emergency
Management, if appropriate. The bill requires DEP to adopt any rules that are necessary to implement these
reporting requirements. (Section 2)
Public Airport Reporting
The bill defines “public infrastructure” as any publicly owned airport used for public purposes.
1 (Section 3)
Beginning on October 1, 2025, the bill requires all operators of public infrastructure to report monthly to the
Department of Transportation (DOT), using a method determined by DOT, the following:
The physical presence of any aircraft
2 on public property, including any public infrastructure, equipped
with any part, component, device, or the like that may be used to support the intentional emission,
injection, release, or dispersion of air contaminants into the atmosphere within the borders of the state
when such emissions occur for the express purpose of affecting temperature, weather, climate, or the
intensity of sunlight.
The landing, takeoff, stopover, or refueling of an aircraft equipped with such components on the physical
location of the public infrastructure. (Section 3)
The bill prohibits DOT from expending any state funds to support a project or program located on or in support of
public infrastructure that is not in compliance with this reporting requirement until such time as the entity
becomes compliant. (Section 3)
Upon receipt of the reports, the bill requires DOT to submit aggregated reports to DEP and the applicable state law
enforcement agency in support of the enforcement of the geoengineering and weather modification ban. The bill
also requires DOT to incorporate reporting guidelines in all grant agreements for public use airports that receive
state funds. The bill authorizes DOT to adopt rules necessary to implement the bill’s provisions. (Section 3)
Other Provisions
The bill repeals all other existing weather modification statutes, including DEP’s weather modification license
program. (Section 1)
The bill removes DEP’s authority to conduct programs of study, research, and experimentation and evaluation in
the field of weather modification. (Section 5)
The bill makes conforming changes. (Sections 4, 6, 7, and 8)
Effective Date
The effective date of the bill is July 1, 2025. (Section 9)
RULEMAKING:
The bill requires DEP to adopt any rules that are necessary to implement the reporting requirements related to
violations of the geoengineering and weather modification ban.
1
See s. 332.004(14), F.S.
2
The bill defines “aircraft” as a powered or unpowered machine or device capable of atmospheric flight, except a parachute or
other such device used primarily as safety equipment. JUMP TO SUMMARY ANALYSIS RELEVANT INFORMATION BILL HISTORY
3
The bill authorizes DOT to adopt rules necessary to implement the reporting requirements for publicly owned
airports.
Lawmaking is a legislative power; however, the Legislature may delegate a portion of such power to executive
branch agencies to create rules that have the force of law. To exercise this delegated power, an agency must
have a grant of rulemaking authority and a law to implement.
FISCAL OR ECONOMIC IMPACT:
STATE GOVERNMENT:
The bill has a negative, indeterminate fiscal impact on DEP related to creating an online form for reporting
suspected geoengineering and weather modification activities and investigating such reports. DEP may also see an
increase in revenues into the Air Pollution Control Trust Fund due to the fines established for conducting
geoengineering or weather modification activities.
DOT may incur costs related to submitting aggregated reports to DEP and law enforcement.
LOCAL GOVERNMENT:
Operators of publicly owned airports may incur costs related to submitting monthly reports to DOT on aircraft that
may be used for geoengineering or weather modification activities.
RELEVANT INFORMATION
SUBJECT OVERVIEW:
Geoengineering and Weather Modification
Weather modification and geoengineering are a range of techniques aimed at manipulating Earth’s climate systems
to modify precipitation or mitigate the impacts of global temperatures. Weather modification, such as cloud
seeding, involves altering local or regional atmospheric conditions to increase precipitation or reduce hailstorms.
Geoengineering, such as solar radiation modification, focuses on larger-scale actions to reduce the amount of
sunlight reaching Earth.
Solar Radiation Modification
Solar radiation modification (SRM) refers to deliberate, large-scale actions intended to decrease global average
surface temperatures by increasing the reflection of sunlight away from the Earth.
3 Extensive research efforts are
underway to gain a comprehensive understanding of SRM technologies. This research focuses on developing and
studying a range of potential future scenarios that combine SRM methods with emissions reductions and carbon
dioxide removal technologies, to varying degrees and over varying timescales.
4 There are several different kinds of
SRM technologies being researched:
Stratospheric aerosol injection (SAI): a strategy that involves injecting small reflective aerosols such as
sulfate into the stratosphere to increase the reflection of incoming sunlight.
Marine cloud brightening (MCB): a strategy for adding aerosol to the lower atmosphere over ocean regions
to increase the reflectivity of low-lying marine clouds.
Cirrus cloud thinning: a strategy for modifying the properties of high-altitude ice clouds to increase the
transmission of outgoing terrestrial radiation to space.
Surface albedo enhancement: increasing the reflectivity of surfaces through, for example, white roofs or
land-cover changes.
3
National Oceanic and Atmospheric Administration (NOAA), Solar Radiation Modification: NOAA State of the Science Factsheet
(hereinafter Solar Modification Factsheet), https://www.climate.gov/news-features/understanding-climate/solar-radiation-
modification-noaa-state-science-factsheet (last visited Mar. 19, 2025).
4
Id. JUMP TO SUMMARY ANALYSIS RELEVANT INFORMATION BILL HISTORY
4
Space-based methods: proposed methods have primarily consisted of large “mirrors” in space to reflect
sunlight.
5
6
SAI and MCB have been the subject of the most research due to their projected feasibility and estimated cost.
7 Most
of the current understanding of these technologies come from theoretical and modeling studies, not field
experimentation. However, the risks and benefits of SAI and MCB are still poorly understood, including their
technical feasibility, efficacy, and potential regional and global effects on the climate, agriculture, and ecosystems.
8
Cloud Seeding
Cloud seeding is the most common method of weather modification and focuses on producing short-term changes
in precipitation, primarily to enhance rain or snowfall or to suppress hail.
9 The most frequently used cloud seeding
approaches rely on the introduction of tiny particles, usually silver iodide, into certain cloud types to trigger the
formation of ice crystals or rain droplets from water already within the cloud.
10 Clouds amenable to these methods
include “cold season clouds” associated with mountainous terrain and “warm season clouds” associated with
convective systems, including thunderstorms.
11 While cold season cloud seeding is reasonably well understood,
substantial uncertainties remain regarding warm season cloud seeding.
12
5
Id.; see also United States Congressional Research Service, Solar Geoengineering and Climate Change, 5-10 (2023), available at
https://crsreports.congress.gov/product/pdf/R/R47551 (last visited Mar. 19, 2025).
6
NOAA, Solar Modification Factsheet (last visited Mar. 19, 2025).
7
Id.
8
See U.S. Congressional Service, Solar Geoengineering and Climate Change at 10, available at
https://crsreports.congress.gov/product/pdf/R/R47551; Samantha M. Tracy et al., Stratospheric aerosol injection may impact
global systems and human health outcomes, Elementa: Science of the Anthropocene, vol. 1, 13-14 (2022), available at
https://online.ucpress.edu/elementa/article/10/1/00047/195026/Stratospheric-aerosol-injection-may-impact-global. See
generally Jessica S. Wan et al., Diminished efficacy of regional marine cloud brightening in a warmer world, Nature Climate
Change, vol. 14 (2024), available at https://www.nature.com/articles/s41558-024-02046-7; Robert Monroe, Scripps
Institution of Oceanography at the University of California San Diego, Artificial Climate Controls Might Become Ineffective—
Because of Climate Change (2024), https://scripps.ucsd.edu/news/artificial-climate-controls-might-become-ineffective-
because-climate-change; Katharine Ricke et al., Hydrological Consequences of Solar Geoengineering, Annual Review of Earth
and Planetary Sciences, vol. 51 (2023), available at https://www.annualreviews.org/content/journals/10.1146/annurev-
earth-031920-083456.
9
U.S. Government Accountability Office (GAO), Technology Assessment: Cloud Seeding Technology (hereinafter Technology
Assessment), 3, 5 (2024), available at https://www.gao.gov/assets/gao-25-107328.pdf (last visited Apr. 1, 2025).
10
Id.
11
Id. at 3.
12
Id. at 5. JUMP TO SUMMARY ANALYSIS RELEVANT INFORMATION BILL HISTORY
5
13
According to the U.S. Government Accountability Office, cloud seeding activities in the U.S. are primarily funded at
the state level or below.
14 As of July 2024, cloud seeding programs were active in at least nine states: California,
Colorado, Idaho, Nevada, New Mexico, North Dakota, Texas, Utah, and Wyoming.
15 Several other states have laws
that address weather modification in some way. In 2024, Tennessee became the first state to ban cloud seeding
and other weather modification operations in the state.
16 Similar bills have been introduced in at least eight other
state legislatures between January 2023 and December 2024, including Illinois, Kentucky, Minnesota, New
Hampshire, Pennsylvania, Rhode Island, South Dakota, and Texas.
17
Weather Modification License
Since 1957, Florida law has required a license for weather modification activities.
18 Applications must be
submitted to the Department of Environmental Protection (DEP) and include:
The name and post office address of the applicant or the person on whose behalf the weather modification
operation is to be conducted if other than the applicant.
The education, experience, and qualifications of the applicant.
The applicant's education, experience, and qualifications.
The nature, object, and general description of the proposed weather modification operation.
The method, equipment, and materials the applicant proposes to use.
19
Each application must be accompanied by a $1,000 filing fee.
20 Applicants must also provide proof of financial
responsibility, namely, a certificate of insurance or a bond to prove their ability to pay damages for accidents
arising out of their weather modification operations in the amount of: $10,000 for bodily injury to or death of one
person resulting from any one incident, and subject to said limit for one person; $100,000 for bodily injury to or
death of two or more persons resulting from any one incident; and $100,000 for injury to or destruction of
property of others resulting from any one incident.
21
13
Id. at 4. (a graphic depicting cold and warm season cloud seeding) (last visited Apr. 1, 2025).
14
Id. at 6 (last visited Apr. 1, 2025).
15
Id.
16
Tenn. Code. Ann. § 68-201-122 (2024).
17
GAO, Technology Assessment at 9 (last visited Apr. 1, 2025).
18
Chapter 57-128, Laws of Fla.; s. 403.301, F.S.
19
Section 403.311(1), F.S. DEP may also require the applicant to submit other pertinent information. Id.
20
Section 403.311(2), F.S.
21
Sections 403.321(1) and 403.321(2), F.S. JUMP TO SUMMARY ANALYSIS RELEVANT INFORMATION BILL HISTORY
6
Prior to beginning operations, the licensee must file with DEP a notice of intention to operate that includes the
licensee’s information and the area and approximate time of operations.
22 The notice must be published in a
newspaper within the county or counties of operation, and proof of publication must be filed with DEP.
23
Licensees are required to maintain a record of all operations conducted pursuant to the license, including the
method employed, the type and composition of materials used, the times and places of operation, and the name
and post office address of each person participating or assisting in the operation other than the licensee.
24 Such
records must be made available to the public.
25
Any person in violation of these requirements is guilty of a second-degree misdemeanor and subject to penalties
including imprisonment of up to 60 days and a $500 fine.
26 Each license entitles the licensee to conduct the
operation described in the application for the calendar year for which the license is issued unless the license is
revoked or suspended.
27 The conducting of any weather modification operation or the use of any equipment or
materials other than those described in the application is cause for revocation or suspension of the license. The
license may be renewed annually by payment of a $50 filing fee.
28 A weather modification license may be revoked
or suspended if DEP finds that the licensee has failed or refused to comply with any requirements related to
weather modification licensing.
29
DEP may grant an emergency license and waive notice requirements if a weather modification operation appears
to DEP to be necessary or desirable in aid of the extinguishment of fire, the dispersal of fog, or another
emergency.
30
According to DEP, there are currently no active weather modification licenses, and there have been no applications
for licenses in recent years.
31
In addition to regulating weather modification licenses, state law also authorizes DEP to study, research, and
experiment in the field of weather modification.
32 However, there is no indication that DEP has been involved in
such weather modification programs.
Federal Weather Modification Regulations
The Weather Modification Reporting Act of 1972 requires anyone who conducts weather modification activities
within the United States to report such activities to the National Oceanic and Atmospheric Administration (NOAA)
Administrator at least 10 days prior to undertaking the activities.
33 The report must include, among other things,
the project’s purpose and location, as well as the modification agents used (e.g., carbon dioxide, sodium chloride,
silver iodide).
34 Another report, which summarizes the project duration and total modification agents dispensed, is
required within 45 days after completion of the project.
35 For ongoing projects, interim reports are required on
January 1 of each year and must include the number of days weather modification activities took place, total hours
22
Section 403.351, F.S.
23
Sections 403.361 and 403.371, F.S. The notice must be published at least once a week for two consecutive weeks in a
newspaper having general circulation and published within any county or counties where the operation is to be conducted and
in which the affected area is located. See s. 403.361, F.S.
24
Section 403.381(1), F.S.
25
Section 403.381(2), F.S.
26
Sections 403.411, 775.082(4)(b), and 775.083(1)(e), F.S.
27
Section 403.331(2), F.S.
28
Section 403.331(3), F.S.
29
Section 403.401, F.S.
30
Section 403.391, F.S.
31
Email from DEP to staff of the Natural Resources & Disasters Subcommittee (Feb. 24, 2025) (on file with the Natural
Resources & Disasters Subcommittee).
32
Section 373.026(6), F.S.
33
15 U.S.C. § 330a; 15 CFR 908.4(a).
34
15 CFR 908.4(a).
35
15 CFR 908.6. JUMP TO SUMMARY ANALYSIS RELEVANT INFORMATION BILL HISTORY
7
of operation, and the amount of agent used.
36 Failure to adhere to these reporting requirements can result in fines
of up to $10,000.
37
Activities subject to these reporting requirements include:
Seeding or dispersing of any substance into clouds or fog to alter drop size distribution, produce ice
crystals or coagulation of droplets, alter the development of hail or lightning, or influence in any way the
natural development cycle of clouds or their environment.
Using fires or heat sources to influence convective circulation or to evaporate fog.
Modifying the solar radiation exchange of the earth or clouds through the release of gases, dusts, liquids, or
aerosols into the atmosphere.
Modifying the characteristics of land or water surfaces by dusting or treating with powders, liquid sprays,
dyes, or other materials.
Releasing electrically charged or radioactive particles, or ions, into the atmosphere.
Applying shock waves, sonic energy sources, or other explosive or acoustic sources to the atmosphere;
Using aircraft propeller downwash, jet wash, or other sources of artificial wind generation.
Using lasers or other sources of electromagnetic radiation.
38
These reporting requirements do not apply to activities of a purely local nature that can reasonably be expected
not to modify the weather outside of the area of operation.
39 This exception is restricted to the use of lightning
deflection or static discharge devices in aircraft, boats, or buildings, and to the use of small heat sources, fans,
fogging devices, aircraft downwash, or sprays to prevent the occurrence of frost in tracts or fields planted with
crops susceptible to frost or freeze damage. Also exempt are religious activities or other ceremonies, rites, and
rituals intended to modify the weather.
40
According to NOAA’s website, NOAA is not currently researching or conducting weather modification experiments
and has no plans to do so in the future. However, NOAA studies the stratosphere and marine boundary layer with
instruments on balloons and aircraft to help fill important gaps in our knowledge and inform decisions about the
potential risks and benefits of solar geoengineering.
41
Federal Aviation Act and Preemption of State Law
The Federal Aviation Act of 1958 gave the Federal Aviation Administration (FAA) the authority to establish safety
standards for interstate and international air transportation.
42 FAA has adopted rules relating to, among other
things, airspace use, air traffic control, aircraft maintenance and registration, and navigational facilities.
43 Courts
have held that Congress, in enacting the Federal Aviation Act and relevant regulations, intended to preempt state
regulation of aviation safety.
44
Federal law also expressly preempts state law in other areas related to aviation.
45 States may not adopt or attempt
to enforce any standard regarding air pollutant emissions from any aircraft or engine thereof unless it is identical
36
15 CFR 908.5.
37
15 U.S.C. § 330d; 15 CFR 908.10.
38
15 CFR § 908.3(a). While all of these activities are subject to initial reporting, NOAA may waive the subsequent reporting
requirements. The decision to waive certain reporting requirements is based on the general acceptability, from a technical or
scientific viewpoint, of the apparatus and techniques to be used. 15 CFR § 908.3(d).
39
15 CFR § 908.3(c).
40
Id.
41
NOAA, Fact check: Debunking Weather Modification Claims (Oct. 23, 2024), https://www.noaa.gov/news/fact-check-
debunking-weather-modification-claims (last visited Apr. 1, 2025).
42
See 1958 Federal Aviation Act, Pub. L. No. 85-726, 72 Stat. 731 (codified as amended at 49 U.S.C. §§ 40101-49105).
43
14 CFR 1-199.
44
Abdullah v. American Airlines, Inc., 181 F.3d 363, 367-368 (3d Cir. 1999). See generally FAA and U.S. Dep’t of Transportation,
State and Local Regulation of Unmanned Aircraft Systems (UAS) Fact Sheet, 1 (2023), available at
https://www.faa.gov/sites/faa.gov/files/uas/public_safety_gov/public_safety_toolkit/FAA%20UAS%20Fact%20Sheet.pdf
(explaining that states and local governments may not regulate in the fields of aviation safety or airspace efficiency but
generally may regulate outside those fields).
45
Federal preemption arises under three circumstances: (1) where Congress has expressly preempted state law; (2) where
state law attempts to regulate a field that Congress intended the federal government to occupy exclusively; or (3) where state JUMP TO SUMMARY ANALYSIS RELEVANT INFORMATION BILL HISTORY
8
to federal standards.
46 In addition, states may generally not enact or enforce laws or regulations related to prices,
routes, or services of commercial air carriers.
47
BILL HISTORY
COMMITTEE REFERENCE ACTION DATE
STAFF
DIRECTOR/
POLICY CHIEF
ANALYSIS
PREPARED BY
Natural Resources & Disasters
Subcommittee
17 Y, 0 N, As CS 4/1/2025 Moore Weiss
THE CHANGES ADOPTED BY THE
COMMITTEE:
Removed provisions that repealed DEP’s weather modification license
program; and
Removed provisions that banned weather modification activities
outright and instead increased the fine for conducting such activities
without a license or violating related provisions from $500 to $10,000.
State Affairs Committee 15 Y, 9 N, As CS 4/17/2025 Williamson Weiss
THE CHANGES ADOPTED BY THE
COMMITTEE:
Prohibited all weather modification and geoengineering activities and
established penalties for any person or corporation who conducts these
activities.
Required DEP to establish an e-mail address and an online form for
anyone to report observed violations of this prohibition.
Required DEP to investigate any report that warrants further review
and refer reports to other specified agencies if appropriate.
Required an operator of a publicly owned airport to report to the
Department of Transportation monthly on the presence of any aircraft
on public property that may be used for geoengineering or weather
modification activities.
Repealed all other weather modification statutes, including DEP’s
weather modification license program.
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THIS BILL ANALYSIS HAS BEEN UPDATED TO INCORPORATE ALL OF THE CHANGES DESCRIBED ABOVE.
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law actually conflicts with federal law, either because it would be impossible to comply with both federal and state regulations,
or because the state regulation “stands as an obstacle to the accomplishment and execution of the full purposes and objectives
of Congress.” R.J. Reynolds Tobacco Company v. Marotta, 214 So. 3d 590, 596 (Fla. 2017) (quoting Vreeland v. Ferrer, 71 So. 3d
70, 76 (Fla. 2011)).
46
42 U.S.C. § 7573.
47
42 U.S.C. § 41713(b).