Who Controls the Weather? Engineering the Sky and the Vacuum of Global Governance

As geoengineering moves from science fiction to reality, ecocide law offers a credible legal framework to protect the Earth and outer space from unpredictable climate technologies presented as solutions.

—

By Anna F. Maddrick

Not long ago, the idea of humanity manipulating the planetary systems that regulate life on Earth belonged largely to science fiction. Today, it is the subject of serious policy debate.

Geoengineering proposals vary widely. Marine cloud brightening would spray salt particles into low-level clouds to increase their reflectivity, while stratospheric aerosol injection would release reflective particles into the upper atmosphere to reduce the amount of sunlight reaching the Earth’s surface. There are schemes to fertilize the ocean with iron to stimulate algal blooms that absorb carbon dioxide, and the Seabed Curtain Project proposes anchoring an 80-kilometer barrier on the ocean floor in front of Antarctica’s Thwaites Glacier to block the warm waters accelerating its collapse. 

Make Sunsets, a US-based company, is already selling “cooling credits” and releasing balloons carrying sulphur dioxide into the stratosphere. Overall funding for solar radiation management research jumped almost three-fold in 2025.

For most of Earth’s history, only nature possessed the power to reshape planetary systems. Ice ages advanced and retreated, volcanoes, asteroids and even the emergence of new species radically impacted the atmosphere. Human societies could transform landscapes, but not the fundamental environmental systems that regulate life on Earth. 

Fossil fuels changed that relationship. By harnessing hundreds of millions of years of stored solar energy and combining it with increasingly powerful technologies, humanity acquired an influence once reserved for planetary forces themselves. Geoengineering, like existing weather modification practices such as cloud seeding, which has been employed for decades in countries including China, the US, the United Arab Emirates and Australia, takes that transformation one step further: from altering the climate unintentionally to attempting to manage it deliberately.

Unlike man-made mechanics, such as a jet engine, which are complicated but fundamentally knowable, the Earth’s climate is a complex system. Its behavior emerges from countless interactions and feedback loops, meaning that interventions in one part can trigger consequences elsewhere that cannot be fully predicted.

The impact of any planetary-scale intervention would necessarily be – well – planetary. 

Models suggest solar geoengineering could disrupt ocean currents and alter precipitation patterns across entire regions, with potentially profound consequences for ecosystems, water supplies and agriculture. Ocean fertilization risks promoting toxic algal blooms that create oxygen-free dead zones, devastating marine food chains. Even an intervention as apparently contained as an underwater barrier in front of a single glacier could interfere with oceanic circulation and disrupt marine life in ways that could well propagate far beyond the intervention site. Each of these proposals involves intervening in systems whose full complexity remains only partially understood. 

The High Stakes and Commercialization of the Global Commons 

The global commons are conventionally understood to refer to the high seas, the atmosphere and outer space: domains that lie beyond any state’s national ownership and form part of collective heritages of humankind, free from claims of territory or privatization. 

At the height of the space race in 1967, the international community responded with the Outer Space Treaty, declaring outer space the common heritage of mankind (CHM) – beyond national ownership, to be used for the benefit of all. While legal scope and application of the CHM principle remains subject to international debate, the principle at its core suggests that some places are too important to be reduced to the interests of individual states and that their governance should reflect responsibilities owed to humanity as a whole. In sustainably managing the increasingly commercialized and militarized global commons, upholding the CHM principle, as well as associated legal frameworks, remains critical.

That principle, however, is increasingly under pressure. The global space economy was valued at more than $600 billion in 2024 and is projected to exceed $1.8 trillion within a decade. More than 14,000 active satellites, often with dual military capacity, currently orbit the Earth, with most operated by private companies. Governments, meanwhile, increasingly treat space as a strategic domain, deploying surveillance satellites, developing anti-satellite weapons and competing for control of the space-based infrastructure upon which modern militaries depend. The existing lack of enforceable regulation, as well as close relationships between private and government actors, poses significant social and environmental concerns. 

No international body effectively governs what private companies can do with the commons they are rapidly colonizing. Reflect Orbital, a US start-up whose ambitions are commercial rather than climatic, is developing a constellation of satellites designed to redirect sunlight to paying customers. “Sunlight on demand,” as the company puts it, with plans to grow from two satellites in 2026 to more than 50,000 by 2035. 

Geoengineering like “sunlight on demand” operates in this same legal vacuum and involves deliberate manipulation of Earth’s radiation environment from space. Proponents of solar geoengineering argue that worsening climate change leaves humanity with little choice. But the fact that climate change presents grave risks cannot mean that every technological intervention becomes justified. The danger here is not simply the risk of unintended consequences, but rather that humanity is developing the power to manipulate planetary systems without any agreed framework for who may do so, under what conditions, and with what accountability. 

That is where ecocide law comes in.

Ecocide Law as a Shield for the Living World 

Every society draws lines around what it considers intolerable, and international criminal law gives expression to some of the most fundamental shared taboos by categorizing them as atrocity crimes: genocide, crimes against humanity, war crimes and the crime of aggression. Ecocide law seeks to extend that framework to humanity’s relationship with the living world. 

In 2021, an Independent Expert Panel of international lawyers defined ecocide as “unlawful or wanton acts committed with knowledge that there is a substantial likelihood of severe and either widespread or long-term damage to the environment.” Like the other core international crimes, ecocide law’s purpose is ultimately prevention: to deter the most serious forms of harm by establishing personal criminal liability for those in positions of power. 

What was once a largely academic and civil society proposal has since attracted active diplomatic and legislative engagement around the world. In 2024, Vanuatu, Fiji and Samoa formally proposed amending the Rome Statute of the International Criminal Court to recognize ecocide as a fifth international crime. Meanwhile, regional initiatives are emerging across Latin America, Europe and Africa, while countries including France, Belgium and, most recently, Mauritius have already enacted standalone ecocide offences. Legislative proposals are advancing in jurisdictions as diverse as Scotland, Italy, the Netherlands, Ghana, India, the Philippines, Argentina and Peru.

Certain actors now have the power to engineer the sky but no legal framework to govern the consequences. Ecocide law would not prohibit scientific inquiry, nor foreclose future debate about geoengineering. What it would do is establish that the global commons are not a legal vacuum; that no actor, however powerful, can cause severe and widespread damage to the systems that sustain all life without facing personal criminal accountability. And at the very least, why invest trillions into developing technologies that have a substantial likelihood to exacerbate the very problems they were created to fix? 

Ecocide law has its historical basis in the Vietnam War, a time where using the environment as a weapon of war, including through weather modification practices, led to international declaration of such conduct as “ecocide” and the development of legal frameworks to protect the environment in armed conflict. 50 years on, the development of geoengineering poses similar international challenges. With a focus on deterrence, accountability and responsibility at the highest levels of governmental and corporate decision-making, ecocide law can explicitly embolden these historical legal frameworks with enforceable modern solutions. 

—

About the author: Anna Faye Maddrick is Legal Adviser on Climate at the Permanent Mission of Vanuatu to the United Nations, New York, and PhD Candidate on Ecocide Law at the University of Bologna, Bologna, Italy