A startup releases sulfur dioxide particles from weather balloons. Researchers propose spraying seawater into clouds. Governments consider injecting aerosols into the stratosphere to cool the planet. Each of these would alter the atmosphere deliberately, at scale, with effects that cross every border on Earth. Who has the authority to do this? The answer, right now, is: nobody, and also anybody.
The climate crisis is real and accelerating. The argument for geoengineering is that emission reductions alone may not happen fast enough to prevent catastrophic warming. If that is true, then active intervention — solar radiation management, marine cloud brightening, enhanced weathering — may be necessary to buy time. To refuse to even research these options could be to condemn billions of people to avoidable suffering.
But the argument against is equally serious. The Earth's climate is a complex system with feedback loops, tipping points, and emergent behaviors that no model fully captures. Injecting particles into the stratosphere to reflect sunlight could alter monsoon patterns, affecting agriculture for billions of people. It could disrupt rainfall in regions that depend on it. The effects would not be distributed evenly — some regions would benefit while others suffer, with no mechanism for the harmed to consent or be compensated.
The termination problem is particularly alarming. Once stratospheric aerosol injection begins, stopping it abruptly would cause rapid warming — the so-called "termination shock." This means the intervention, once started, would need to be maintained indefinitely, committing future generations to a program they did not choose and cannot safely end.
And the moral hazard is real. If governments and publics believe that geoengineering offers a safety net, the political will to make the difficult, expensive choices required to cut emissions could weaken. The existence of a "plan B" can undermine commitment to plan A — even if plan B is unproven, risky, and incomplete.
The Day After Tomorrow is the book's entry point for thinking about climate as a complex system — a system where small perturbations can trigger cascading, irreversible changes. The film gets the science wrong in its specifics (the timeline is absurdly compressed), but the underlying insight — that climate is not a thermostat you can adjust — is profoundly right.
Intergenerational Responsibility is the ethical heart of this question. Geoengineering does not just affect the people who decide to implement it. It affects every generation that comes after. The termination problem means we would be binding our grandchildren to a maintenance program for the atmosphere, with no way for them to opt out safely. See What do we owe people who haven't been born yet?
Could We? Should We? at planetary scale. The technology to alter the atmosphere is becoming available. The question is not whether someone will try — that is already happening (see Active Geoengineering Proposals). The question is whether it will be done with coordination, governance, and accountability, or unilaterally by whoever has the resources and the will.