In 2024, the Copernicus Climate Change Service (C3S) reported alarming new records in global greenhouse gas levels, alongside unprecedented rises in air and sea surface temperatures. These escalating climate crisis indicators have triggered extreme events worldwide, wildfires ravaging forests, heatwaves sweeping across regions, and catastrophic floods reshaping landscapes. Confronted by the growing severity of this global crisis, an influential coalition of scientists, billionaires, and technocrats has emerged with an ambitious proposal: the deployment of solar geoengineering, or solar radiation modification (SRM) technologies.
Their mission is clear, to alter the global climate system itself in a desperate bid to halt the relentless advance of global warming.
No longer conspiracy theory
The fossil fuel industry continues to refuse any commitment to reducing global production, deliberately ignoring the devastating consequences they inflict on our planet. Will the adoption of solar geoengineering give the industry and polluters a convenient excuse to maintain their business-as-usual approach?
Solar geoengineering fails to address the root causes of the climate crisis, merely treating the symptoms while allowing greenhouse gas concentrations to keep rising unchecked.
Olaf Corry, professor of global security challenges at University of Leeds with focus on the security implications of geoengineering technologies, said:
There is a political risk that solar geoengineering could be used or misused, potentially contributing to a broader effort to delay or avoid the radical decarbonisation and social and economic transformations necessary to properly and sustainably address the climate crisis.
SRM, or solar geoengineering technologies, include marine cloud brightening (MCB), space-based approaches involving placing mirrors, shades or reflecting particles in the space between the sun and earth, and stratospheric aerosol injection (SAI), which involves the injection of particles into the stratosphere.
The most extensively studied method is SAI, where sulphur dioxide is released into the stratosphere at altitudes of 20-25 km. This technology simulates the effect of a volcano eruption, like the eruption of Mount Pinatubo eruption in the Philippines on 15 June 2001. The injected particles help form clouds that reflect some of the incoming solar radiation back into space, resulting in a cooling effect.
‘Research is accelerating’
In an interview with climate tech expert, Dan Miller on 12 January, David Keith, professor in the department of the geophysical sciences at the University of Chicago, stated that geoengineering is more effective at cooling the planet than CO2 reduction. He added:
Research is accelerating. I think nobody has any idea what’s going to happen.
A bunch of the data shows that cold northern places actually benefit a little bit from climate change. I think it’s a mixed bag. I personally oppose climate change because I care about the natural environment.
I think tipping points are primarily a political construction, people in the mainstream science community don’t take them very seriously. Tipping points were constructed carefully to produce a kind of political outcome
On January 17 2022, over 60 senior climate scientists and governance experts worldwide initiated a global effort advocating for an international agreement to prohibit the use of solar geoengineering. To date, a coalition of more than 500 academics from over 60 countries has signed an open letter supporting this initiative. They argue that deploying this technology as a potential climate policy option presents an unacceptable risk.
Frank Biermann, professor of global sustainability governance at Utrecht University, said:
The recent developments around solar radiation modification are deeply disturbing. The complete risks of eventual SRM deployment are unknowable, and there are at present no plausible global governance mechanisms to deal with such planetary-scale intervention technologies.
Furthermore, there is a high risk that the current proposals for more SRM research will eventually delay or even derail all efforts to mitigate climate risks by bringing down greenhouse gas emissions.
Risks and doubts around solar geoengineering
The Royal Society of Chemistry’s scientific assessment, along with various other reports and articles, indicates that the implementation of SAI could result in numerous negative consequences, such as heatwaves, droughts, ozone depletion, and disruptions to weather and climate patterns.
Stratospheric ozone depletion contributes to higher levels of UV-B radiation reaching the Earth’s surface, which can adversely affect human health, marine and terrestrial species, causing DNA damage and raising the risk of cancer.
The deployment of SAI could also disrupt hydrological cycles and influence extreme weather events, including tropical cyclones, hurricanes, and an increase in the frequency of storms.
Moreover, the potential impacts are projected to be particularly severe for communities most vulnerable to climate change, such as those in coastal regions and tropical areas.
SAI could pose significant health risks due to the inhalation of suspended particles and the ingestion of particles through water and food sources.
Additionally, excessive cooling from volcanic eruptions, like the effects of deploying SAI technology, has led to events like volcanic winters, such as the 1815 eruption of Mount Tambora, which caused the “year without a summer” and resulted in a global food shortage, as seen in 1816.
Once SAI is implemented, we could become permanently reliant on it with no option to reverse the process. This is known as “termination shock.” If SAI were suddenly halted, the natural climate cycle would resume, leading to a rapid temperature increase, potentially two to four times higher, which could be difficult to manage.
Corry highlighted additional risks associated with research, development, and deployment of solar geoengineering technologies:
Geopolitical dynamics are already at play and have been recognised; decision-making around research, development, and potential deployment of solar geoengineering technologies is unlikely to be guided solely by climate risk management. We cannot assume these technologies will be deployed rationally or for purely altruistic global purposes – they will also serve geostrategic interests. The world doesn’t think – let alone act – like a climate scientist.
Solar geoengineering technologies are likely to be driven not solely by climate concerns, but by factors such as security, control, and economics.
Geopolitical unrest could be fuelled by solar geoengineering
One of the most alarming aspects of solar geoengineering lies in the geopolitical risks and governance challenges it presents. A dominant nation or a coalition of powerful countries could take the lead in deploying this technology, potentially inflicting immediate and profound harm on other regions. At present, there is no comprehensive multilateral governance framework to oversee the research or deployment of solar geoengineering, leaving the world vulnerable to its unchecked consequences.
Corry explained:
I’m not opposed to solar geoengineering research or the technology per se – but not the current unilateral free-for-all, hoping for some unspecified ‘governance’ down the line. If there were a global moratorium coupled with a coordinated multilateral research effort that considered legal, ethical, and geopolitical concerns, as well as other forms of knowledge beyond just scientific, I would support such research. As things stand, I believe any responsible researcher should be on board with a moratorium on deployment, with a push for responsible, governed research.
Solar geoengineering modelling experiments leave out geopolitical and governance challenges, according to a research article co-authored by Corry, and published at Review of International Studies (RIS).
Concerns about the weaponisation of solar geoengineering have been dismissed as either false or vastly exaggerated, largely due to the perceived geophysical “imprecision” of the technology.
If solar geoengineering is weaponised, it has the potential to deepen global inequality and escalate conflicts worldwide. It could be used as a strategic tool in negotiations, targeted in conflicts, or even provoke new sources of conflict. We already exist in a political landscape incapable of reaching fair, collective agreements. Some nations may view unilateral solar geoengineering initiatives as a direct threat to their national security, prompting retaliatory actions that could destabilise international peace and security.
Weaponising the tech
In his interview with Miller, Keith was asked how world leaders, unable to reach a consensus on climate change action, could possibly agree on a governance framework for solar geoengineering. He replied:
World leaders never agree on anything, and world leaders didn’t perfectly agree on climate action, and yet we have climate action, so basically nothing in the world has actually been done by some magic consensus, and yet a lot still happens.
So solar geoengineering, I think if it’s implemented in the next decades, it’ll be implemented by some small coalition of countries and the question is, what’s the coalition of countries that want to do it , how stable is that coalition, how representative is it of the kind of south versus north, and what would the coalition look like that oppose it or why would they oppose it, but that’s the way in practice that international rules will work, it won’t work by some UN level single unanimous vote.
The United Nations Environment Assembly (UNEA), the global body responsible for making key decisions on environmental matters, consists of 193 member states. However, governments have been unable to reach a consensus on a multilateral governance framework concerning the research and deployment of solar geoengineering technologies, both during UNEA’s fourth session in March 2019 and its sixth session in March 2024.
Corry highlighted another troubling concern regarding the deployment of solar geoengineering:
Disinformation or propaganda about solar geoengineering could be generated and disseminated by a range of actors, including major powers like the USA, Russia, or China. Imagine the political strain it would put on climate and atmospheric science and the potential for controversy.
Moreover, solar geoengineering could be blamed for negative weather or climate events – such as droughts, floods, or storms – and framed as a form of atmospheric colonialism, exacerbating disruptions in climate-vulnerable regions of Asia and Africa.
Who’s pushing solar geoengineering?
Billionaires, state and private investors, NGOs, and financial and technology institutions from Silicon Valley and Wall Street are backing research into solar geoengineering technology. This coalition includes individuals and organisations with significant ties to both corporate and political power
Prominent private funders of solar geoengineering technologies include the Fund for Innovative Climate and Energy Research (FICER), Bill Gates’ personal fund managed by Ken Caldeira and David Keith, and Silver Lining, a non-profit backed by LowerCarbon Capital, with executives from Goldman Sachs and JP Morgan on its board. The Simmons Foundation, established by hedge fund billionaire Jim Simmons, and his wife, is also supporting SG initiatives.
Dustin Moskovitz, co-founder of Facebook, along with partners Cari Tuna and Holden Karnofsky, funds the solar geoengineering project, Open Philanthropy Project. William Hewlett, founder of Hewlett-Packard, is another investor in solar geoengineering technologies. The Environmental Defence Fund (EDF), which has corporate ties with companies like Citigroup, GE, McDonald’s, Shell, Tyson and Walmart, is another prominent backer.
Other funding organisations include the Alfred P. Sloan Foundation of General Motors, the Pritzker Innovation Fund, founded by the Hyatt Hotels Corporation’s founders, and the VK Rasmussen Foundation.
US-based start-up Make Sunsets and Israeli company Stardust Solutions are actively working to commercialise solar geoengineering. In 2023, Make Sunsets released aerosol-filled balloons in Baja California, Mexico, without the Mexican government’s consent. This led Mexico to say it would ban such experiments in its territory – although legislation has not yet been introduced. Stardust Solutions has reportedly begun indoor testing of a system designed to disperse reflective particles, with funding sources linked to the Israeli military and security sectors.
Is it worth the risk?
In his research article published in the Journal of Political Ecology, Kevin Surprise, senior lecturer in environmental studies at Mount Holyoke College, points out that the US is currently the only nation with the capacity for unilateral solar geoengineering deployment in the foreseeable future.
Surprise’s article suggests that the Harvard Solar Geoengineering Research Programme (HSGRP) is the global leader in SAI research. It maintains connections with the Weatherhead Centre for International Affairs and the Belfer Centre for Science and International Affairs, both of which have long-standing relationships with the defence and intelligence sectors.
HSGRP is developing the first outdoor SAI field experiment, the Stratospheric Controlled Perturbation Experiment (SCOPEX), in collaboration with Raven Aerostar, a Department of Defence contractor specialising in border security and surveillance, with contracts involving the US Navy and Air Force.
Corry highlighted further risks tied to the potential radical measures the new US administration might choose to implement:
The risks seem clear to me – it’s all too tempting for figures like Trump or Musk to claim it’s a solution or frame the problem purely as one of temperature and propose a solution that directly targets it.
We’ve already seen right-wing US figures claim that climate change discussions are driven by communists or ideologues aiming to take away your beef, SUV, or even dismantle capitalism. If the issue is narrowly defined as temperature alone, this approach could easily be presented as a cheaper or even preferable ‘solution’.
He added:
Comparing risks can enhance decision-making but choosing which versions of the future to compare and which risks to take out can be very arbitrary, and you need to be super careful. solar geoengineering should be evaluated specifically in relation to the climate risks it aims to address, not all climate risks.
Alternative approaches, such as degrowth or the phase-out of fossil fuels, should also be assessed alongside solar geoengineering. Comparisons need to include geopolitical, ethical, and social risks, in addition to environmental ones even if they are harder to quantify.
Furthermore, public participation is crucial throughout the process, from identifying risks to determining the appropriate actions.
Featured image via the Canary
