Warming to a false dawn: It is time the world regulates the sector of solar geoengineering

Abstract of this article appeared in Financial Express

Unfortunately, the Vienna Convention is toothless, and its provisions have been ignored. Therefore, rebooting the Vienna Convention to govern SRM research is essential.

Solar radiation modification (SRM), a group of technologies to deliberately reflect sunlight into space to cool the planet, is now being seriously explored as a solution to the climate crisis. In theory, injecting sulphur droplets into the stratosphere, salty water into clouds, or scattering glass over polar ice could slow global warming by changing the Earth’s energy balance. But as these experiments involve risks at a planetary scale, we should proceed with abundant caution, communication and transparency, regulated by globally agreed standards. Instead, we see ethical and legal boundaries being crossed by unregulated experiments.

Reckless experimentation

Since 2017, a private initiative, initially called Ice911 Research and later the Arctic Ice Project, has scattered tiny glass spheres to reflect sunlight over 17,500 square metres (or three football fields) of Arctic ice, drawing protests from Alaska Native leaders. Full deployment would involve spheres over 100,000 square kilometres of the Arctic, an area the size of Bihar.

Some of the recent experiments are even more reckless. In 2022, an independent researcher in the UK released sulphur dioxide from a high-altitude weather balloon into the stratosphere and named it SATAN (Stratospheric Aerosol Transport and Nucleation). Around the same time, Make Sunsets, a Silicon Valley-backed start-up, launched nearly 50 such balloons from Mexico. This company now plans to sell “cooling credits” for such launches.

The start-up’s response to the question “Is this legal?” is: “Yes, we’ve been in contact with multiple US government agencies (FBI, FAA and NOAA). They are aware of our business and activities.” This non-answer is at the heart of the problem. Here’s why: Experiments that pose planetary risks violate international law if those risks are not clearly assessed, communicated, and consulted on beforehand. This is true even though there is a lack of specific national regulation, which some wrongly believe gives them a free rein. Let me elaborate.

Global warming or ozone hole

Two significant scientific assessments published in 2023 underlined the hazards of SRM. The first, the One Atmosphere report of the UN Environment Programme (UNEP), found that “even as a temporary response option, large-scale SRM deployment is fraught with scientific uncertainties”. To address the evident “critical unresolved issues around equity, ethics and consent” around SRM, it recommended a “robust, equitable and rigorous trans-disciplinary scientific review process” based on a precautionary approach.

The second, the World Meteorological Organization’s 2022 Scientific Assessment of Ozone Depletion, found that while injecting sulphur into the stratosphere “could reduce some of the impacts of global warming, it cannot restore past climatic conditions and would very likely cause unintended consequences, including changes in stratospheric ozone concentrations”. It also found that the certainty of damage to the ozone layer increases with prolonged and more intensive use of these methods. This finding sits uncomfortably with a finding from UNEP’s One Atmosphere report: that SRM would need to be maintained for several decades or centuries to limit warming effectively and that abruptly stopping the intervention would lead to “rapid climate change that would increase risks for humans and ecosystems”. Therefore, SRM poses a binary choice: Short-term use could exacerbate global warming, whereas long-term deployment risks significantly damaging the ozone layer.

International law

These findings on the transboundary impacts of SRM have legal implications. There are many international conventions and agreements that call for regulation of activities threatening large-scale modification of planetary systems such as oceans, the ozone layer, climate, and biodiversity, even if their precise effect is not fully understood.

Take the case of the London Convention on the Prevention of Marine Pollution. In 2008, the Convention prohibited a type of geoengineering known as ocean fertilisation, except for research that undertakes a risk assessment, develops a risk management plan, and commits to sharing and publicising findings through peer review. In 2010, parties to the Convention on Biological Diversity (CBD) agreed to prohibit geoengineering in general, with a narrow exception for research.

The Vienna Convention for the Protection of the Ozone Layer is particularly pertinent to Solar SRM. The Convention, ratified by all countries, obligates countries to cooperate on research on “substances, practices, processes and activities that may affect the ozone layer, and their cumulative effects”. Therefore, unregulated unilateral experiments that affect the ozone layer, such as SRM, violate this obligation.

Unfortunately, the Vienna Convention is toothless, and its provisions have been ignored. Therefore, rebooting the Vienna Convention to govern SRM research is essential. Such regulatory processes are also critical at the national level because government support for SRM research is growing in countries like the US and China. While the scale of experiments is currently small, they will likely grow more ambitious. Without a robust regulatory process, the fuzzy line between researching and carrying out geoengineering will be crossed without warning. The potential impacts—such as ozone layer degradation and sudden shifts in global climate—will affect populations worldwide, most of whom have had no say in whether such experiments should proceed.

This is especially important because many countries already use technologies to modify local weather. China plans to bring about 5.5 million square kilometres of its territory under a weather modification programme by 2025. A team in Australia is injecting saltwater into clouds over the Great Barrier Reef to prevent its disappearance. The leap from weather modification to SRM is close.

The stakes for countries like India in geoengineering cannot be overstated. Computational models indicate that SRM could negatively influence monsoon patterns, affecting agriculture and water availability. Hence, it is crucial for India to spearhead the development of an international regulatory framework for SRM, including outdoor experimentation. This proactive approach is essential, as decisions made today will have implications for generations to come.