Different Takes: Climate Stabilisation as a Framing for Solar Geoengineering

When I look at the world, I see the critical work of mitigation progressing, but too slowly, with necessary carbon removal on an even longer timeline. Meanwhile, adaptation protects some humans and their systems, but not the Earth systems now destabilizing due to warming – sea ice, permafrost, ocean circulation, planetary reflectivity – each with its own feedbacks and on its own clock. If mitigation and adaptation aren’t realistically going to work on the timeline these systems are at risk, what set of things might we do on that timeline, and what research and engineering must we do today to make anything we collectively choose to do as low-risk as possible?

Solar geoengineering sits inside this field as a potential intervention, as do ice sheet stabilization and work on warming-induced emissions. So does the decision that an intervention shouldn’t be used at all. And the people most exposed – Arctic Indigenous communities, small island states, Global South populations – need standing in these decisions, not consultation afterward.

I call this work Earth systems stabilization. Like mitigation and adaptation, it will eventually get shortened to one word (or cast off by the wayside), but right now it is actively being defined. It names a category of work matched to the timeline we face and aimed at the highest-risk feedbacks – work that today has vanishingly few people or resources behind it.

Stability is a lovely word to yearn for. An “intervention” can sound like something done to you, and unfortunately stability is what everyone, everywhere, is currently short of.

The difficulty, however, may be hiding a little lower down. In mapping seventy-five climate interventions for a taxonomy, my colleagues and I kept finding that what people do and how the planet responds are analytically distinct aspects of intervention. People could inject aerosols, brighten a cloud, or blanket a glacier, but all that follows the point of intervention cascades through atmospheric chemistry, ocean circulation and ecological response – once an intention is actioned, it is no longer controllable. Holding global temperature steady with stratospheric aerosols would still set off responses of its own. Steadier, by one measure – and different by others. “Stable” might be a larger claim.

A field that promises stability will be measured against that promise, and droughts, floods, extreme heat or other adverse effects may persist or change even if an intervention achieves its specified objective. The safer and more honest course is for each intervention to go by its own name and make its own case. Cloud brightening over a reef is not aerosols in the stratosphere, and neither necessarily require an umbrella term to be taken seriously – although if one must be used, it should favour what they are (climate interventions) over what they hope to achieve so that we do not oversimplify the earth system response for a too-narrow target.

Exploring the utility of “climate stabilization” responds to a real problem. Climate impacts are accelerating, and research into the full range of responses, including SRM, deserves support.

Most folks I’ve talked with about this term are considering it in good faith, wondering “can this help”? But a few are trying to advance it in campaign mode, working to enforce a perception of consensus rather than building it through engagement with climate and other communities. The question is presented as settled. That’s wrong as a process and ineffective as a strategy. Early blowback is already visible. We should worry that this will make the case for scaled research harder, not easier.

What the term encompasses also remains unsettled, even as consensus is asserted around it. And the idea has had little time to circulate or be tested beyond Europe and the United States.

Some current advocacy risks implying more than science has established about what SRM in particular could do in response to AMOC collapse or sea level rise.

In the end, if umbrella terms like climate stabilization can help some people conceptualize where SRM research might fit within a broader response landscape, that can be useful. But we shouldn’t waste time relearning that durable support for research is built via engagement, capacity building, and legitimate processes.

Space-based measurements by NASA’s CERES instruments show that Earth’s energy imbalance (EEI) – the net exchange of energy between Earth and space and the underlying driver of global warming – has more than doubled since 2000. Remarkably, this increase is driven entirely by a decrease in planetary reflectivity – mostly less sunlight reflected from clouds, ice, and snow.

Given this key role for declining reflectivity in driving global warming, it might seem logical to use declining reflectivity as the sole or primary justification for researching SRM. It is tempting to think that restoring lost reflectivity provides an easy justification for SRM. This argument is overly simplistic, however, and it neglects and obscures important reasons to pursue research into both EEI and SRM.

Understanding the causes and implications of the rapid increase in EEI is one of the most important problems in climate science today, and regardless of cause, the rapid increase in EEI is a 5-alarm fire which should motivate a range of actions including accelerated mitigation, increased investments in adaptation, and (yes) research into potential interventions including SRM. Similarly, there are strong reasons to pursue SRM research besides declining reflectivity. These include ongoing high – and even still growing – human greenhouse gas emissions, the apparent onset of warming-induced emissions (from permafrost, wetlands, etc), and a growing appreciation that we may be close to crossing important climate tipping points.

“Climate stabilization” sounds reassuring. It suggests bringing the climate system back under control and holding it there. But when the term gets attached to solar radiation modification (SRM), it’s worth pausing on. Stabilization isn’t a purely technical outcome. Whose climate counts as stable, at what temperature, with what regional fallout: these are political questions before they’re technical ones.

SRM might lower global mean temperature or ease some risks, but that’s not the same as stabilizing the climate. Temperature is one variable in a much messier system, and precipitation, ecosystems, and regional vulnerability won’t necessarily move together. Calling it “stabilization” implies a level of predictability and control that the research doesn’t actually support.

The framing matters for governance too, because the words we use shape how a technology gets understood before anyone decides whether to use it. Calling SRM a “stabilization” tool quietly shifts the conversation from whether it should happen at all to how it should be rolled out. Plainer language would keep the actual stakes in view: who decides, who’s affected, and how little we know.

The framing of climate stabilization is an interesting addition to the debate on solar geoengineering. The notion of stabilization also implies a self-contained intervention that does not destabilize other aspects of the climate system. Let’s pause and ponder.

The SRM360 brief on monsoon disruption concludes: “SAI would generally weaken monsoon rains, but the net change would vary across regions and would depend on the combined effects of climate change, air pollution, and how SAI is deployed.” Evidently, SRM cannot stabilize the climate for billions who depend on the monsoons not just for farming but also for their potable water supplies. Fun fact: Its impact on India’s economy is so extensive that the monsoon is often referred to as “India’s finance minister.” Yet the Indian government and elite opinion-makers do not always represent the concerns of those who will be most directly affected. The justice effects of solar geoengineering cannot be deduced from national identities, let alone from the binaries of the Global North versus the Global South.

No matter what aggregate statistics of solar geoengineering models show, its effects are likely to be differentiated along the lines of caste, class, gender, ethnicity, and political marginalization. This begs several questions: what is being stabilized, who wins, and who loses out in the process? The systemic inequalities that fall differentially along a gradient of disadvantage, which shape the justice effects of solar geoengineering, cannot be understood through the reductive thinking that underpins climate science and its models. This is why genuine interdisciplinary debates and collaborations with transnational environmental and climate justice movements are indispensable for respectful and meaningful dialogue around solar geoengineering.