A World on Fire

Now, what if I were to tell you that some, if not all, of the challenges that I described could be addressed much like a damaged bridge in need of repair or the installation of solar panels on a home? More specifically, I am referring to the potential humanity has to “engineer” itself out of this bind through a fringe scientific field known as geoengineering. As I will describe in the coming sections, there is tangible evidence and data that suggest geoengineering could help combat worsening climatic conditions. However, at the same time, there remain serious, often unspoken and unsavory, risks associated with the field, demanding skeptical evaluation and thorough planning. Public mistrust, political manipulation, and uncertainty regarding long-term effects are just a few of the many risks associated with the technology.

From my research and analysis of the topic, I found compelling evidence both in fervent support and highly critical of geoengineering. Therefore, it is my informed opinion that the technology should be pursued, but only if strict regulations and oversight are put into place. As I will explain further later, geoengineering should supplement current initiatives to curtail climate change, not act as an alternative to present efforts, namely cuts to greenhouse gas emissions. While some may have hoped for a clear yes or no answer to the overarching question, “Should humanity rely on geoengineering?” the reality is that the situation is far more nuanced and precarious. Humanity is taking a significant gamble with its time, resources, and future through geoengineering, requiring decisions to be made in a careful manner. Depending on its management, geoengineering could either help save the planet or contribute to its destruction.

Disclaimer Regarding Anthropogenic Influence on Climate Change

Before definitively assessing the benefits and drawbacks of geoengineering, it is necessary to clarify a few assumptions underlying my research, analysis, and writing of this blog. First and foremost, I evaluate geoengineering in the context of climate intervention, since the field is predominantly centered on the problem of global warming. Although geoengineering is not theoretically limited to this purpose, with historical applications including cloud seeding and artificial rainfall, nearly all modern discussions view the field as a climate protection strategy. Accordingly, my analysis repeatedly considers geoengineering and its related concepts in terms of their feasibility and value in this regard.

A second consideration is the contentious debate surrounding the cause of climate change. While the warming of the planet in recent decades is well documented, disagreements remain among some members of the scientific community, as well as the general public, regarding the exact source of these trends, enough so that I found it appropriate to acknowledge it here. A comprehensive 2021 study examined 88,125 peer-reviewed climate papers published from 2012 to 2020 and found that more than 99.9% of them either explicitly or implicitly support the anthropogenic explanation for climate change [9]. Only 28 papers expressed any form of doubt [9]. Although I have not independently reviewed those papers or extensively assessed the methodology of the study, the overwhelming consensus in the scientific literature suggests that most geoengineering research is likely conducted under this anthropogenic assumption. Therefore, to meaningfully discuss geoengineering and the studies that examine it, I adopted the same analytical framework.

The question of whether humanity is responsible for climate change lies outside the scope of this blog, so my adoption of the anthropogenic framework should not be interpreted as a statement of reality. Instead, the focus of this blog is to discuss humanity’s capacity and willingness to pursue technologies that could counteract current climatic trends. For the sake of consistency, this discussion proceeds on the implicit basis that geoengineering seeks to address warming that is human-caused.

Geoengineering: Climatic Manipulation

Geoengineering is defined as the intentional, large-scale manipulation of the environment to alter Earth’s climate systems, often to combat climate change [4]. There are two main categories of geoengineering, each with distinct benefits and drawbacks.

Carbon Dioxide Removal (CDR) removes carbon dioxide (CO₂) from the atmosphere and stores it in long-term geological and biological sinks (Figure 1), such as limestone and forests, respectively [4]. CO₂, along with other greenhouse gases like methane (CH₄), captures heat within Earth’s atmosphere by preventing thermal radiation from escaping to outer space, meaning that reducing its concentration supports the natural cooling of the planet [4]. Techniques of CDR include direct air capture (DAC) with chemical filters, ocean alkalinity enhancement, bioenergy with carbon capture and storage (BECCS), and afforestation [4]. While CDR is generally less environmentally intrusive compared to other geoengineering methods, it is expensive to implement at large scales and slow to produce measurable results.

Solar Radiation Management (SRM) reflects incoming solar radiation, preventing Earth from absorbing additional heat [5]. Like CDR, it targets a core driver of climate change: the source of warming. However, whereas CDR works by removing greenhouse gases and allowing heat to escape, SRM only reduces the net influx of thermal energy. Therefore, anthropogenic sources of heat can still contribute to global warming, even if surface temperatures are temporarily lowered or held constant by SRM initiatives. Techniques of SRM include stratospheric aerosol injection (SAI), which mimics volcanic cooling by emitting sulfur aerosols into the air (Figure 2 and Figure 3), cirrus cloud thinning, and space-based reflectors [5]. Compared to CDR, SRM is more environmentally invasive, as it requires introducing artificial chemicals into the atmosphere. Additionally, abruptly stopping SRM activity could trigger a “thermal rebound,” effectively undoing any positive effects the technology had achieved [24].

Two specialized forms of SRM are marine cloud brightening (MCB) and glacial engineering. MCB, like SAI, involves the seeding of low-lying clouds with sea-salt particles (Figure 4), which increases their albedo (i.e., their ability to reflect sunlight) [7]. According to some estimates, this process can potentially lower regional temperatures by 1-2 °C [7]. Glacial engineering aims to preserve glacial mass (Figure 5) through artificial underwater sills and, in some cases, CO₂ injections beneath the ice, incorporating elements of CDR [8]. Ice naturally reflects large amounts of sunlight, so stabilizing glaciers enhances Earth’s reflectivity and helps mitigate sea-level rise caused by melting ice [8]. While glacial engineering is generally less disruptive compared to other SRM techniques, its improper implementation could accelerate ice loss, cascading into regional devastation [8]. 

Although I have yet to incorporate empirical data or specific figures, the “unsavory” aspects of geoengineering are already evident from these brief overviews. In particular, the intrusive nature of SAI and MCB raises serious concerns about humanity’s potential role as a perpetual regulator of the climate. How long would such interventions need to remain active for global temperatures to return to preindustrial levels? When accounting for the threat of thermal rebounding, it becomes increasingly clear that SRM techniques are unlikely to serve as the “one-and-done” solutions some may interpret them to be. If adopted, the injection of chemicals into the atmosphere would almost certainly need to persist for years before termination could be considered a safe option. In other words, if SRM is the path humanity chooses to follow, it cannot easily deviate from it without risking further harm to the planet.

That being said, the broader field of geoengineering still contains promising and reasonable avenues for climate remediation. While SRM appears fundamentally limited in its ability to safely stabilize the climate, CDR remains an intriguing and comparatively unobtrusive means of temperature reduction. Its primary challenges are linked to cost and scale; however, given the significant resource expenditure associated with current – often unsuccessful – efforts to combat climate change, it is reasonable to set this concern aside for the time being. For reasons that I will address later, CDR represents the approach humanity should prioritize, as it harnesses nature’s existing mechanisms for cycling carbon. Put more succinctly, CDR enhances the thermal permeability of the atmosphere and avoids the introduction of artificial substances into it. Despite the confidence I place in CDR, my original stance on geoengineering remains unchanged – and will be further clarified soon: geoengineering should support climate stabilization, not serve as the primary force in counteracting global warming.

A Brief History and Modern Glimpse of Geoengineering

Modern geoengineering emerged after World War II, fueled by Cold War technological competition and growing concerns about imminent environmental collapse [4]. In the 1960s, the creation of “artificial volcanoes” was proposed to US officials [4]. These devices would inject sulfur compounds into the stratosphere to cool the planet, serving as a precursor to what would later become stratospheric aerosol injection (SAI) [4]. The idea regained traction in 1991 after the eruption of Mount Pinatubo, which released large quantities of aerosols into the atmosphere, reportedly cooling Earth by 0.6 °C for nearly two years [4].

The contemporary concept of SAI remained on the fringes of the scientific community until 2006, when Nobel laureate and meteorologist Paul Crutzen published a study proposing it as a climate protection strategy [5]. The Royal Society’s 2009 report and the 2010 Asilomar Conference established voluntary research principles for geoengineering [5]. By 2015, the U.S. National Academies endorsed the study of SRM while emphasizing strict governance and oversight [5]. In 2018, the Carnegie Climate Geoengineering Governance Initiative (C2G2) was launched to promote global dialogue on the field [5].

As of 2025, CDR pilots capture thousands of tons of atmospheric CO₂ each year through direct air capture, though scaling still requires massive amounts of investment [2]. SRM research largely remains confined to computer simulations and models, but several real-world developments indicate a serious growing interest in the technology. Namely, the NOAA’s SABRE (Stratospheric Aerosol processes, Budget and Radiative Effects) mission studies the influence of stratospheric aerosols on the environment, the governments of Germany and China fund SRM research, and the European Union is developing regulatory frameworks to monitor the scope of such studies [5]. Yet in 2024, the UN Environment Assembly failed to impose limits on SRM research, leaving a dangerous void in regulation [5].

From this brief timeline, it becomes clear that significant uncertainty and concern continue to surround the study and application of geoengineering. Major environmental conferences and international assemblies consistently place the issue at the forefront of discussion, particularly in recent years. These developments further contextualize and reinforce my position that geoengineering – regardless of how it may ultimately be implemented, if at all – must be governed by strict guidelines and oversight, with my primary reasoning explained in the following section.

Tragedy of the Commons: Climate as a Shared Resource

In 1968, ecologist Garrett Hardin warned that finite, shared resources would inevitably degrade without enforced regulation from an authoritative body [3]. He termed this dynamic the “Tragedy of the Commons,” describing how the self-interested behavior of individuals results in the corrosive exploitation of common resources that lead to destructive outcomes for all those involved (Figure 6) [3]. Greenhouse gas emissions follow this exact logic: the pollution from a single factory contributes to the warming of the entire planet.

Earth’s atmosphere functions as a “global commons,” since no particular nation, organization, or individual has sole ownership of it, and all people depend on its stability and health for survival. Geoengineering, if mismanaged, could intensify the degradation of the atmosphere, rather than save it. A single country attempting to cool its territory could inadvertently redirect hurricanes, disrupt crop cycles, or increase the temperature of neighboring regions. Without enforceable international agreements, a bad actor could manipulate the atmosphere for their own strategic advantage, leaving the global population to face the consequences. Hardin understood this fact very well, advocating for “mutual coercion” (i.e., forceful, mutually agreed-upon regulation) to protect the broader community, which in the case of geoengineering would extend to the entire planet [3].

The relevance of the Tragedy of the Commons to the atmosphere is crucial to understanding my hesitation toward embracing all forms of geoengineering. While evidence may highlight the cooling potential of various techniques, the underlying risk persists: the improper handling of geoengineering technology could further destabilize the climate, as repeatedly alluded to in the form of the thermal rebound effect. Despite its resilience, the atmosphere can deteriorate beyond repair. As Hardin argued, rigorous governance must be established not only to regulate greenhouse gas emissions but also to oversee the deployment of technologies aimed at countering them. While I do not possess the necessary wisdom to recommend which governing body should be responsible for such oversight, I maintain that, when it comes to environmental intervention, some level of regulation is far better than none at all. Ultimately, the goal of geoengineering should be to alleviate an existing climatic tragedy, not accelerate or intensify it.

In recent years, geoengineering has advanced significantly, moving from computer-simulated models to physical, real-world experiments. My research identified numerous studies from the past decade that investigate a range of techniques and present extensive data on their effectiveness in mitigating global climate change. In this section, I focus on three relevant studies – one examining CDR, one evaluating SAI, and one assessing MCB – and provide brief summaries of each. At the end of this section is an analysis that connects my findings to my earlier points and also begins to address the central question, “Should humanity rely on geoengineering?”

CDR: Shallow Geologic Storage of Carbon

Researchers in a 2023 study near Clemson, South Carolina, tested Shallow Geologic Storage (GCS), a CDR approach that injects solid carbon-based materials (such as wood) into shallow formations beneath Earth’s surface [10]. This process not only sequesters CO₂ but also elevates terrain, offering an added benefit in the form of flood protection [10].

During field tests, researchers injected a slurry composed of wood, water, and guar gum at depths of 1.8-2.4 m [10]. Across a combination of single-injection and multi-injection trials, they stored approximately 22 tons of CO₂-equivalent underground, with an average rate of 1.2 tons/day (Figure 7) [10]. A larger injection area (182 injections across 650 m²) produced a localized uplift of 70-105 mm at the injection sites, with an average uplift of about 38 mm across the entire area [10].

A full life cycle analysis of a theoretical 2.1-hectare deployment indicated that, over two years, this method could store approximately 17.3 thousand tons of CO₂-equivalent while emitting only 549 tons – resulting in a net storage efficiency of roughly 97% [10]. Additional examinations showed that anoxic conditions minimized carbon loss (less than 8%) [10]. Under favorable conditions, submerged biomass could persist for thousands of years before completely decomposing [10].

The study ultimately supports the feasibility of GCS as a long-term carbon removal and storage strategy [10]. Projections suggest that – with a sufficient supply of biomass – this technique could store between 0.1-1 gigatons of CO₂-equivalent annually [10]. Beyond carbon removal, the method also functions as a meaningful strategy for flood mitigation [10]. Despite these benefits, the researchers note several concerns, including the potential for groundwater contamination, long-term biomass degradation (resulting in decreased efficiency and uplift), and induced seismicity associated with large-scale injection in concentrated areas [10].

SRM: Stratospheric Aerosol Injection (SAI)

Researchers used the UK Earth System Model (UKESM1) to simulate a worst-case scenario in which greenhouse gas emissions remain high for the foreseeable future (SSP5-8.5) [11]. To determine the scale of intervention required to approximate a medium-emissions future (SSP2-4.5), they tested two versions of stratospheric aerosol injection (SAI) frameworks, each aiming to limit warming to about 2 °C rather than 5 °C by the end of the century [11]. One approach (G6sulfur) injected sulfur dioxide near the equator at roughly 20 km above sea level [11]. The other (G6controller) employed an automated feedback system that injected aerosols at latitudes around 15° and 30° N/S at approximately 21.5 km in altitude [11]. This feedback design was designed to prevent significant temperature disparities between the Northern and Southern Hemispheres and to avoid overcooling the tropics or undercooling the poles [11].

Both strategies reduced global warming by roughly 3 °C by 2100, but insightful differences emerged (Figure 8) [11]. The equatorial method required about 705 Tg of SO₂ over the duration of the simulation, while the multi-latitude approach used approximately 645 Tg (about 10% less) [11]. Cooling in the equatorial scenario was more concentrated in the tropics, resulting in diminished temperature effects at the poles [11]. This approach also reduced global precipitation by about 4% (0.14 mm/day) and intensified drying in the Amazon [11]. By contrast, the multi-latitude method produced a more uniform cooling pattern, limited precipitation loss to 2.7% (0.09 mm/day), and reduced Amazon drying [11]. Ozone depletion and stratospheric heating were additional concerns in the equatorial trial, whereas these effects were significantly reduced under the multi-latitude instance [11].

The study concludes that multi-latitude aerosol injections outperform equatorial injections, generating fewer and less severe negative outcomes in relation to precipitation, circulation, and stratospheric chemistry [11]. Overall, the researchers find that SAI can meaningfully mitigate global warming, but only if implemented with careful planning and a thorough approach that is designed to minimize unintended climatic impacts [11].

SRM: Marine Cloud Brightening (MCB)

Similar to the SAI study, researchers used the UK Earth System Model (UKESM1) to simulate marine cloud brightening (MCB) and evaluate the scale of intervention needed to shift the current worst-case emissions trajectory (SSP5-8.5) toward a more moderate outcome (SSP2-4.5) by the end of the 21st century [12]. In this experiment, sea-salt aerosols were introduced into clouds across four regions in the eastern Pacific – an area totaling roughly 52 million km² [12]. The resulting scenario (G6MCB) was then compared with a similarly scaled SAI simulation (G6Sulfur) to identify differences in both the magnitude and spatial distribution of climatic effects [12].

While SO₂ injections in the G6Sulfur model peaked at about 21.1 Tg/year to reach the desired cooling target, the G6MCB scenario required an extraordinary 413 Tg/year of sea-salt aerosols – approximately 20 times the amount needed in the SAI approach (Figure 9) [12]. The model sought to reduce incoming solar radiation by roughly 1 W/m² globally; however, over the regions where sea salt was injected, the reduction reached nearly 4 W/m², noticeably dimming the sky. Early in the simulation, each additional million tons of sea salt corresponded to nearly 0.02 °C of global cooling, but by 2100, the projected efficiency fell to approximately 0.006 °C.

Overall Assessment of Geoengineering Studies

The three studies examined in this section – Shallow Geologic Storage of Carbon (CDR) [10], Stratospheric Aerosol Injection (SAI) [11], and Marine Cloud Brightening (MCB) [12] – collectively demonstrate that geoengineering has progressed well beyond being a purely theoretical science. The technological capacity to implement and evaluate these strategies now exists. Although the SAI and MCB studies relied primarily on advanced simulations, they nevertheless provided global-scale assessments of their effectiveness and detailed reports on their climatic effects [11] [12]. The Shallow Geologic Storage approach proved capable of storing up to scales of 1 gigaton of CO₂-equivalent annually while also offering the benefit of improved flood protection to the tested area [10]. Similarly, the SAI and MCB simulations showed the potential to reduce end-of-century warming by roughly 3 °C under high-emission scenarios [11] [12]. From these findings, it is reasonable to conclude that humanity is technically capable of engineering interventions that can meaningfully combat global warming. However, the deeper question remains, “Should humanity rely on geoengineering?”

Addressing the moral and strategic dilemmas associated with each category of geoengineering first requires a clear review of their risks. CDR is generally viewed as less environmentally intrusive, yet the Shallow Geologic Storage study highlights several concerns, particularly those related to the operation’s scale and the location of carbon storage [10]. Large quantities of sequestered carbon must be relocated to secure geological formations, and if not properly managed, the process could threaten groundwater quality or destabilize subsurface ecosystems [10]. SRM techniques demonstrated considerable cooling potential, but their effects on regional precipitation patterns (and the amount of aerosols required to establish an effective cooling system) varied widely across the models examined [11] [12]. Ozone depletion, observed in certain SAI simulations, introduces another layer of concern [11]. It is also important to note that all SRM findings relied on computer simulations [11] [12]. While these models are highly sophisticated and incorporate complex representations of Earth’s climate, they are not physical, empirical evidence of SRM’s effects. Ultimately, any meaningful assessment of SRM’s real-world performance would require physical experimentation – an action that involves releasing massive quantities of particles into the atmosphere and accepting the possibility of irreversible and unintended consequences.

The notion of being able to solve climate change through technical ingenuity is an intriguing thought. Human innovation has enabled our species to achieve extraordinary achievements, such as placing a man on the moon (and bringing him back to Earth), eradicating once-fatal diseases through the development of vaccines and cures, and placing enormous computational power in the hands of millions in the form of smartphones. However, not all problems require novel, innovative solutions. Some are best addressed by the simple elimination of their underlying causes. This leads me to my central point: the most effective way to mitigate global warming is to reduce greenhouse gas emissions (Figure 10). Rather than constructing elaborate systems or cooling apparatuses across the globe to match worsening atmospheric conditions, it is more efficient to curtail the anthropogenic emissions at their source. This logic aligns with the principles behind CDR, which I also believe to be the most sustainable and dependable form of geoengineering.

For these reasons, regardless of the potential they may have demonstrated in simulations, SRM strategies – specifically SAI and MCB – remain too unpredictable and too dependent on invasive alterations to Earth’s climate systems to be considered reliable forms of geoengineering. While some may interpret these limitations as obstacles to be overcome for the greater good of the planet, they introduce a considerable amount of uncertainty and the possibility for unintended consequences, which, in my view, nullify much of their perceived promise. Although the downsides of CDR can be mitigated through robust oversight and controlled operations, the same cannot be said for SRM.

Dark Side of Geoengineering: Risks that Cannot be Ignored

As established in the previous section, geoengineering is technologically feasible in the present era. Although it may require a significant amount of investment, development, and maintenance before it can be implemented in any meaningful manner, it is nonetheless a capability that humanity currently possesses. However, as previously suggested, feasibility does not necessarily constitute imperativeness. What happens when humanity’s planetary-scale intervention goes wrong? Who assumes responsibility for its deployment? Who will govern the operation after deployment? How can the public be assured that genuine geoengineering is occurring and not something else, something more sinister?

This section directly addresses these concerns, along with the central counterarguments posed against geoengineering employment. Issues such as oversight, public trust, moral hazards, and historical instances of inadvertent climate manipulation shine light on the social, political, and ethical risks involved, which are often understated. If the technical limitations and harmful environmental influences from these strategies were insufficient to raise doubt about their reliability, then examining the social dimensions of geoengineering demonstrates why caution – and preferably outright avoidance – is warranted and necessary.

Who Controls the Global Thermostat?

Since the 2024 UN Environment Assembly failed to impose limits on the scope of geoengineering studies, the field currently operates in a regulatory vacuum [5]. In other words, any private institution or government can pursue geoengineering without serious restrictions, provided that they do not explicitly violate regional or international laws. While several countries (as well as many US states) are currently in the process of composing legislation to constrain the operations of these private actors, many continue to exploit the anarchy.

United Kingdom: The Advanced Research and Invention Agency (ARIA) – a subsidiary of the UK government – funds approximately 22 projects worth £56.8M with the objective of “Exploring Climate Cooling,” including outdoor trials of Arctic sea-ice thickening and marine cloud brightening. These are the first SRM field tests in the UK backed by the state [15].

United States: Harvard’s Solar Geoengineering Research Program (SGRP) is able to model SAI will little oversight [17]. 22 US states have introduced bans in 2025 aimed at halting the advance of geoengineering, with Tennessee and Florida enacting laws [16] [18].

Private Sector: Over $100M from private donors like SilverLining and Pritzker fund new geoengineering initiatives (Figure 11), without the need for approval through some democratic process [19].

While unrestricted action involving the climate may not seem inherently controversial, the context changes significantly when the potential environmental harms of certain geoengineering practices are factored into the equation. Under these conditions, such freedom becomes far more troubling and does not bode well for the future. As explained in the introductory section of this blog, the absence of authoritative regulation over a shared resource inevitably invites private, selfish actors to exploit and eventually degrade it [3]. Current geoengineering activities may already be following this path.

Another important political concern is the lack of a democratic process in authorizing geoengineering research and deployment. Despite the potential to influence (and harm) millions – if not billions – of lives, there is no technical requirement for national or regional approval before operations can begin. Granted, some areas are moving to impose restrictions on this behavior, meaning that large-scale deployment would likely face some degree of resistance from lawmakers or governing bodies. For instance, the Environmental Protection Agency recently investigated Make Sunsets’ SO₂ balloons due to being unauthorized [20]. Nevertheless, the absence of formalized rules adds to the risk, as actors capable of causing harm through negligent (or intentionally nefarious) geoengineering practices may face little to no legal punishment as a result.

Developments such as these were fundamental in shaping my belief that strict regulation and governance are essential, regardless of the extent to which geoengineering is used in the future. No matter the scale, the technology is specifically designed to modify the environment, and while many may hope that such applications will always be conducted with humanity’s best interests in mind, there is no guarantee that this will hold true. As a result, there is a dire need for structured oversight – ideally, a responsibility shared among multiple bodies, people, etc. – to prevent corruption and irreparable environmental damage. As noted earlier, I do not claim to possess the education or expertise required to identify such an authority, but I remain convinced that such an entity must exist; otherwise, we put our faith and trust in the presumed benevolence of humanity, which has historically been rarely effective.

Conspiracy, Distrust, and Moral Hazards

While my earlier concerns about a bad actor deploying geoengineering with malicious intent may seem like isolated paranoia, survey data suggest that I am not alone in this line of thinking. Two national, representative surveys – one from 2024 (N=3,076) and another from 2022 (N=2,109) – examined the awareness, attitudes, and beliefs of Americans regarding solar geoengineering (SG), with particular attention given to SAI and MCB [21] [22].

2024 Study (N=3,076):

• 57.5% of respondents learned about SG for the first time in 2024 [21].
• Only 32.6% supported funding SG research [21].
• 43.7% opposed supporting SG, and 23.5% were neutral [21].
• 1.3% of respondents spontaneously mentioned chemtrails when prompted with the question, “What is the first thing that comes to mind when you think about solar geoengineering?” [21].
• About 20% believed the U.S. government was conducting secret SG programs (e.g., spraying chemicals into the atmosphere), and nearly half were unsure (Figure 12) [21].
• 71.3% approved of university-led SG research, compared to 43% who preferred government oversight [21].

2022 Study (N=2,109):

• 54% had heard nothing about SG in the previous year [22].
• Only 9% of unfamiliar conservatives expressed optimism about geoengineering’s climate effectiveness, compared to 64% of liberals [22].

Taken together, these findings indicate that the general public is not only skeptical of geoengineering but, in many cases, unaware of its existence entirely. A particularly notable point is the roughly 20% of respondents who expressed distrust toward the government’s potential involvement in secretive GS practices [21]. This figure suggests that my concerns about the possibility of concealed deployments were, at the very least, not isolated. The more pressing questions then become a matter of what such deployments – if they exist – intend to accomplish. Are they occurring for the benefit of society, or could they have more sinister goals? To foster trust, greater transparency is needed, not only in geoengineering research but across all aspects of public policy.

The 2022 study also found that increased familiarity with SG was linked to a greater likelihood of supporting geoengineering instead of emissions reduction (or a combination of both) [22]. This result aligns with my earlier emphasis on emissions reduction as the primary and most effective mechanism for mitigating climate change, while also illustrating the problematic assumptions that can arise from a limited understanding of the broader factors at play. The belief that geoengineering can replace emissions mitigation is a false solution – a so-called “moral hazard.” As discussed previously, continued release of carbon-based molecules into the atmosphere will further reduce its thermal permeability, thereby forcing humanity to invest in a more aggressive geoengineering approach. Essentially, the more humanity relies on fossil fuels, the more energy and resources must be devoted to counteracting their byproducts, creating a diminishing, inefficient cycle. In summary, although certain geoengineering techniques may offer temporary cooling benefits, they will never match the efficiency or long-term reliability of reducing greenhouse gas emissions.

Inadvertent Geoengineering: CFCs and Ozone Depletion

Humanity has already run one unplanned, global geoengineering experiment – and it nearly ended all life on Earth. In the 1970s and 1980s, everyday products like refrigerants, aerosol sprays, and foam packaging contained chlorofluorocarbons (CFCs), synthetic chemicals that drifted up into the stratosphere where UV light splits them apart, releasing chlorine atoms that destroyed ozone, with one atom of chlorine being able to wipe out roughly 100,000 ozone molecules before it is finally depleted [23]. The result of this massive accidental release of CFCs into the atmosphere was massive ozone holes forming over Antarctica (and smaller ones elsewhere), allowing far more UV radiation to reach Earth’s surface, causing skin cancer rates to surge, crop yields to drop sharply, and threatening marine ecosystems and global food production [23]. And this is not some conspiracy; it is a well-documented event in modern history – how humanity unknowingly nearly cooked the planet [23].

In a rare turn of global events, 197 countries signed the Montreal Protocol in 1987, phasing out CFCs and related compounds (Figure 13), with ozone now recovering and full healing expected by 2060–2070 in most regions [23]. If the chemicals in hair spray could have nearly destroyed the planet, it is frightening to think what might happen if SAI is handled negligently – more ozone loss? Acid rain? Climatic chaos? CFCs showcased the destructive capability of man on the planet’s climate, and that was not even intentional – geoengineering, if in the wrong hands, will certainly be capable of being far deadlier and more destructive.

Conclusion and Final Verdict

Now that we have examined what geoengineering is, what it is capable of, and the concerns surrounding it, the core question remains: Should humanity rely on geoengineering to address climate change? Unlike questions of technical feasibility, this one does not have an inherent or universally correct answer, as different people prioritize different values. However, if we draw upon the evidence discussed above, we can arrive at the conclusions that have been woven throughout this report.

Geoengineering involves the intentional, large-scale manipulation of the environment to influence Earth’s climate systems. It is commonly divided into two categories: Carbon Dioxide Removal (CDR) and Solar Radiation Management (SRM). SRM includes techniques such as stratospheric aerosol injection (SAI) and marine cloud brightening (MCB), both of which introduce particles into the atmosphere to reflect incoming sunlight. CDR, as the name suggests, involves methods that capture and store atmospheric carbon.

CDR is generally effective at reducing anthropogenic carbon concentrations by storing captured CO₂ in terrestrial sinks such as subsurface formations. Its primary limitations are the extensive investment required to develop large-scale carbon-capturing technologies and infrastructure, along with the surveying, permitting, and preparation of land as storage sites. Additional concerns include the risk of groundwater contamination from leaks and potential ecological disruption near injection sites. However, with appropriate planning, monitoring, and environmental protection policies, the risks associated with CDR can be mitigated.  

SAI and MCB, by contrast, can theoretically deliver substantial cooling, though most of the evidence supporting this comes from computer simulations rather than empirical testing. A central concern with these SRM techniques is the depth of unintended and uncontrollable side effects associated with atmospheric manipulation. Simulations suggest that precipitation patterns and stratospheric ozone concentrations could be significantly disrupted by large-scale aerosol injections, raising the possibility that these approaches might ultimately cause more harm than good. Some studies even warn of a potential “thermal rebound” effect (a rapid warming that could occur if long-term SRM deployment suddenly stops). Given the scale and volatility of Earth’s atmosphere, these strategies may simply be unmanageable in practice. 

From this information alone, CDR appears to be the lesser of two evils. Poorly executed CDR can certainly yield negative outcomes, but it remains comparable to modern terraforming or environmental engineering projects – ambitious but generally manageable when safeguards are built into the planning process. SAI and MCB, meanwhile, function more like unpredictable wildcards, strategies too risky to rely on given the inherent fragility of climate systems. That said, adopting CDR at the scale required to remove billions of tons of carbon will be very labor-intensive and resource-heavy. This raises the question: Is there a simpler solution? There is: greenhouse gas emissions reduction. 

By limiting carbon emissions at their source, we slow the intensification of the greenhouse effect and allow natural carbon cycling to play a greater role in stabilizing atmospheric concentrations. While this shift prompts broader discussions about viable long-term energy systems, it remains the most immediate and reliable means of reducing warming trends. If natural processes prove insufficient or too slow, CDR can serve as a supplemental tool to further decrease atmospheric carbon.

One comparison that repeatedly emerged in my mind during the research process was the analogy between geoengineering and nuclear energy (Figure 14). Both possess the capacity for immense good or catastrophic harm, depending on human judgment and governance. Although I did not explicitly emphasize it earlier, there is a legitimate concern that geoengineering could be used as a weapon for war, much like how nuclear technology was harnessed in the form of the atomic bomb. Yet, despite these risks, geoengineering can still yield positive outcomes if subjected to rigorous oversight and strict regulations. Certain SRM approaches, however – namely SAI and MCB – are inherently unstable and cannot be easily halted once deployed. Humanity should therefore rely only on methods that are dependable and controllable. 

For those still uncertain about my stance on geoengineering – or climate change mitigation as a whole – I encourage you to explore the topic further. My report only scratches the surface of the available research, and many important debates remain regarding the viability, safety, and appropriate role of various geoengineering strategies in humanity’s future.

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Sources

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[3] Tragedy of the Commons. (n.d.). Econlib. Retrieved October 31, 2025, from https://www.econlib.org/library/Enc/TragedyoftheCommons.html

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