The World’s Scientists Are Arguing About Whether or Not to Block the Sun

Global Scientific Community Debates Solar Radiation Management as Climate Solution

Three experts recently voiced their concerns about solar geoengineering following a debate at the United Nations.

Solar geoengineering involves the theoretical concept of reflecting sunlight away from Earth using technology. This method is often discussed as a potential strategy to mitigate climate change impacts.

Proponents of this idea stress it should only be considered as a last-ditch effort, to be explored if absolutely necessary.

Switzerland suggested the United Nations create a group to study solar geoengineering, a subject that stirs much debate due to its focus on technological interventions to prevent the sun from exacerbating climate change. However, the proposal did not materialize as member countries could not agree on the group’s potential roles and objectives. This highlights the contentious nature of solar geoengineering, despite it being largely theoretical at this stage. The question arises: Are we overlooking a critical chance to directly address climate change?

Geoengineering encompasses any artificial attempt to alter Earth’s climate. It includes concepts like terraforming, which is the process of making uninhabitable planets suitable for human life by replicating Earth’s air and water cycles. Solar geoengineering specifically aims to cool the Earth by reflecting sunlight away from the planet.

In response to Switzerland’s initiative, three researchers from James Cook University in Australia and Wageningen University in the Netherlands criticized solar geoengineering as a risky diversion. They highlighted potential dangers such as unpredictable outcomes, loss of biodiversity, threats to food security, and violations of human rights across generations. They argue that the focus should instead be on eliminating fossil fuels and promoting a global transition to sustainable practices.

Science, particularly climate science, can be a source of controversy, influenced not only by the scientific facts but also by political and media dynamics. Solar geoengineering has faced skepticism, partly due to its portrayal as a villain in popular culture.

Harvard University canceled a planned solar geoengineering experiment in 2021 due to public backlash. The project aimed to test equipment for dispersing particles into the atmosphere to block sunlight, without actually releasing any particles. Critics, including indigenous communities in Sweden, viewed the experiment as a moral hazard.

In 2022, the Massachusetts Institute of Technology proposed a space-based solar geoengineering study, suggesting it would pose less risk to Earth’s atmosphere. The project’s proponents argue that geoengineering could be a last resort if climate change becomes too severe.

The debate over solar geoengineering is marked by urgency. After years of insufficient action on climate change, scientists are increasingly desperate for solutions. Switzerland’s proposal for a UN discussion group on solar geoengineering aimed to consolidate research and skepticism, providing a resource for further study.

An essay on The Conversation discussed the hypothetical risks of solar geoengineering technologies, suggesting they could take a century to implement. These speculative risks underscore the unknowns of applying such technologies in the real world, as well as the complex implications for food security and human rights.

One experiment attempting to reflect sunlight using seawater in the Great Barrier Reef failed to lower water temperatures significantly. This outcome provides valuable data, demonstrating the importance of exploring and understanding solar geoengineering’s potential and limitations. Dismissing the discussion as harmful only hinders progress in climate science.

During UN discussions, nations from the Global South advocated against the use of solar geoengineering. However, conducting real-world research could reveal unforeseen consequences and inform global emission reduction strategies.

The saying “the proof of the pudding is in the eating” applies here. To understand the potential of solar geoengineering, we must be open to exploring and discussing it, even if on a small scale. Without such exploration, we may miss opportunities to address climate change effectively.