The same technologies that might cool our planet could also become tools for conflict in a warming world.
Imagine a world where countries don't just battle with traditional weapons but wield climate itself as a tool of war—where manipulating weather patterns becomes a strategic capability, and fears of environmental sabotage shape international relations. This isn't science fiction; it's the emerging security dilemma surrounding geoengineering: deliberate, large-scale interventions in Earth's systems to counter climate change.
As global temperatures continue to break records, with 2024 officially becoming the first year where average warming exceeded 1.5°C 2 , interest in these radical technologies is accelerating. What began as a theoretical response to climate emergency now confronts a harsh reality: Any technology capable of altering planetary systems could potentially be weaponized—or at least perceived as such by nervous nations 4 . From conspiracy theories about government weather manipulation to genuine security concerns at the highest levels of international diplomacy, the debate over geoengineering is evolving from purely scientific inquiry to a matter of global security.
Geoengineering encompasses technological approaches designed to deliberately alter the climate system to counter the effects of global warming. These approaches generally fall into two broad categories, each with different methods, risks, and implications.
Aims to reflect a small percentage of sunlight back into space before it can heat the Earth. The concept takes inspiration from volcanic eruptions like Mount Pinatubo in 1991, which released particles that cooled the planet by approximately 0.5°C for over a year 9 .
The most studied approach, Stratospheric Aerosol Injection (SAI), would involve releasing reflective particles into the upper atmosphere to create a cooling effect 5 .
Takes a different approach, seeking to extract greenhouse gases directly from the atmosphere or ocean through methods ranging from massive tree-planting campaigns to direct air capture technologies 2 .
While potentially less controversial than SRM, current CDR capacity remains minimal—approximately 2.2 billion metric tons of carbon dioxide annually, primarily through afforestation 2 .
| Approach | Example Methods | Intended Effect | Key Risks & Uncertainties |
|---|---|---|---|
| Solar Radiation Management (SRM) | Stratospheric Aerosol Injection, Marine Cloud Brightening | Rapid cooling by reflecting sunlight | Altered rainfall patterns, ozone depletion, geopolitical tensions |
| Carbon Dioxide Removal (CDR) | Afforestation, Direct Air Capture, Ocean Fertilization | Reduce atmospheric CO2 levels | Slow acting, resource intensive, potential ecosystem damage |
The concept of "weather warfare" has long captured the popular imagination, but how realistic is it that geoengineering could be transformed into a weapon?
From a purely technical perspective, most security experts find the concept of directly weaponizing solar geoengineering unlikely. Militaries typically prefer precise, reliable tools that can be targeted against enemies—capabilities that SRM technologies notably lack 4 .
Deliberately causing an environmental catastrophe in a specific geography using stratospheric aerosol injection would be extraordinarily difficult, since any government deploying it would inevitably affect their own territory too 4 .
Similarly, more localized techniques like Marine Cloud Brightening would be difficult for a foreign actor to deploy covertly against another country, given the substantial logistical requirements including ships, port access, and sustained operation 4 .
The greater security risk lies not in direct weaponization, but in how these technologies might exacerbate existing tensions between nations. In a world already characterized by what the Munich Security Conference describes as "multipolarization"—where more states than ever can influence global events, yet cooperation has become increasingly difficult—the introduction of climate intervention technologies could become a dangerous flashpoint 4 .
A country might deploy solar geoengineering while ignoring or accepting the potential negative effects on other regions, creating a scenario that—while falling short of actual weaponization—could easily be perceived as hostile action 4 .
History shows that perceptions often matter as much as reality in international relations, particularly in regions with preexisting tensions.
The theoretical debate over geoengineering is rapidly giving way to practical experimentation, moving from computer models to carefully controlled real-world tests.
In 2025, the UK's Advanced Research and Invention Agency (Aria) announced a £56.8 million program funding real-world geoengineering experiments across the globe 6 . These include sending weather balloons into the stratosphere to release milligram samples of non-toxic mineral dust and testing how seawater sprays can make oceanic clouds more reflective 6 .
"Decarbonisation is the first and best chance of avoiding these tipping points. But the current trajectory puts us in danger of triggering some tipping points, regardless of what happens with net zero, so we do need to think about what we might do in that eventuality."
| Tool/Material | Function | Application in Research |
|---|---|---|
| Weather Balloons | Carry instruments or materials to stratospheric altitudes | Test particle behavior under real stratospheric conditions |
| Mineral Dust (Alumina, Calcite) | Alternative reflective particles to sulfates | Research materials with fewer side effects than traditional sulfates |
| Seawater Spray Systems | Generate tiny seawater droplets to brighten marine clouds | Study marine cloud brightening potential for localized cooling |
| Drone Technology | Precise delivery of atmospheric materials | Enable targeted experimentation with cloud seeding techniques |
Perhaps the most alarming aspect of geoengineering's rapid development is the absence of comprehensive international governance frameworks to guide research, much less deployment.
Currently, the European Union has adopted a mixed approach—encouraging investment in carbon removal technologies while taking a precautionary stance toward SRM 2 . At the international level, only the 1978 Environmental Modification Convention (ENMOD) specifically addresses weather modification for hostile purposes, and it was drafted long before modern geoengineering concepts were developed 4 .
This governance vacuum creates what researchers at the Carnegie Endowment have identified as three distinct categories of catastrophic risk 2 :
Rapid temperature increase if SRM is deployed but suddenly stopped
Cascading failures across ecosystems and societies
Irreversible Earth system changes caused by delayed emissions reductions
The governance challenge is further complicated by the weaponization of geoengineering discourse through disinformation campaigns. False claims about "chemtrails" have evolved from fringe conspiracy theories to elements of mainstream political discourse, with several U.S. states passing legislation to ban "geoengineering" based on misinformation 4 .
These false narratives have serious security implications. As the Center for Climate & Security notes, "Domestic disinformation on geoengineering in the United States amplifies and provides opportunities for foreign malign influence from Russia and China" 4 . Following the 2023 Maui wildfires, China ran a clandestine social media campaign blaming a U.S. military "weather weapon"—demonstrating how geoengineering fears can be leveraged as hybrid warfare tools 4 .
The security dimensions of geoengineering extend beyond direct weaponization to encompass how these technologies might destabilize already fragile international relationships.
Nowhere are these dynamics more concerning than in regions like South Asia, where countries including China, India, and Pakistan share multiple major river basins, and climate change is simultaneously increasing both drought risks and flooding 4 . Water has recently become a significant point of tension between India and Pakistan, with the latter accusing India of "weaponizing" water by opening dams on shared rivers during extreme precipitation events 4 .
In this volatile context, uncertainty about how SRM deployments might affect critical weather patterns like the South Asian monsoon could exacerbate existing tensions. India has already accused China of worsening downstream droughts and floods through its extensive dam-building, and has suggested that increases in natural disasters along their shared border might result from Chinese weather modification programs 4 .
Nature of Threat: Unpredictable changes to weather patterns
Potential Consequences: Disrupted monsoons, ozone depletion, ecosystem damage
Nature of Threat: Perception of hostile climate manipulation
Potential Consequences: International conflicts, accusations of weather warfare
Nature of Threat: Hybrid warfare through disinformation
Potential Consequences: Social unrest, domestic extremism, infrastructure attacks
Nature of Threat: Disruption to agriculture and infrastructure
Potential Consequences: Food insecurity, resource conflicts, economic instability
The debate over geoengineering as a potential weapon represents more than just a theoretical security concern—it signals humanity's entry into what researchers at the Carnegie Endowment have termed the "age of planetary security" 2 . In this new era, security considerations must expand beyond traditional military concerns to encompass the fragile interplay between human, technological, and ecological systems.
The greatest danger may not be that any single country would deliberately weaponize climate technologies, but rather that the mere existence of these capabilities—coupled with accelerating experiments and a vacuum of international governance—could trigger misunderstandings, accusations, and escalations in a world already grappling with climate-driven instability.
As nations and private entities advance geoengineering research, the conversation must extend beyond scientific feasibility to address the profound ethical and security implications of technologies that could potentially alter Earth's systems for centuries to come.
The ultimate question may not be whether we can engineer our climate, but whether we can develop the wisdom to govern these powerful technologies without unleashing new forms of conflict in an already fragile world.