Real-world geoengineering experiments are being conducted globally, from the Arctic to the Great Barrier Reef, with funding from the UK government. These experiments include testing solar-reflecting particles in the stratosphere, spritzing seawater to enhance cloud reflectivity, and manipulating water thickness.
The Advanced Research and Invention Agency (ARIA) notes that acquiring this “critical missing science data” is vital for addressing several catastrophic climate turning points. If deemed safe, geoengineering could provide a temporary cooling effect on the planet, buying time to address the root causes of the climate crisis, such as fossil fuel consumption.
Before any large-scale implementation, ARIA emphasizes that experiments will be conducted at a reduced scale and under strict oversight. Further components of the £56.8 million program will involve modeling the potential impacts of geoengineering and exploring international governance issues.
Geoengineering is contentious; some scientists classify it as a “dangerous distraction,” suggesting it diverts focus from emission reductions and raises concerns about unintended climate ramifications. Previous plans for outdoor experiments faced cancellation due to considerable pushback.
However, proponents argue that given the relentless rise in emissions and increasingly severe climate events, researching geoengineering technologies becomes essential. The ARIA initiative is complemented by a £10 million project, positioning the UK among the leading funders of geoengineering research globally.
“Decarbonization is our first line of defense against these tipping points,” stated Professor Mark Symes, ARIA’s Program Director. “Nonetheless, the current trend threatens to trigger tipping points, irrespective of efforts to reach net zero, so we really need to contemplate how we’ll respond should those scenarios unfold.”
“The aim is to thoroughly investigate whether any proposed cooling methods can be applied safely,” he added. “If tipping points occur, life in the UK could become quite challenging.”
Ilan Gur, ARIA’s CEO, expressed optimism, saying, “If science can prove that well-designed seawater sprays could protect the Great Barrier Reef’s incredible biodiversity, wouldn’t we want to pursue that knowledge?”
Criticism emerged from Professor Raymond Pierrehambert at Oxford University, who remarked that proceeding with field experiments without solid governance—either domestically or internationally—seems reckless.
Mary Church of the International Centre for Environmental Law cautioned, saying, “Solar power’s inherent unpredictability poses risks to an already compromised climate system. Small experiments could normalize controversial theories, leading us down a slippery slope.”
Most geoengineering strategies aim to block sunlight from warming the Earth’s surface, yet solar radiation management (SRM) could provoke serious unintended effects, such as alterations in rainfall essential for food production. Some private companies are already delving into geoengineering, underscoring the need for a solid scientific foundation, Gur noted.
The ARIA-financed experiments involve deploying weather balls in the US or UK, which will release non-toxic mineral dust samples at high altitudes to study how particle characteristics evolve.
In three other experiments, techniques using drones to disseminate seawater spray target cloud formation over oceans, intended to increase sunlight reflection. One of these will expand existing work over the Great Barrier Reef, while another will take place along the British coastline.
The fifth experiment focuses on injecting water into Canadian sea ice during winter, covering about 1 square kilometer. In summer, the water freezes, preserving ice sheets for longer. Bright white ice reflects much more sunlight than the dark water exposed when sea ice diminishes.
Before any outdoor experiments commence, an environmental impact assessment will be made available for community consultation. ARIA has also established an independent oversight committee, chaired by leading climate scientist Piers Forster, with members from India and Ghana.
The ARIA initiative is also exploring the feasibility of space reflectors, specialized sunshades designed for orbit. “This is the most speculative approach we’re funding,” remarked Symes. Natural events, such as volcanic eruptions, already introduce particles into the atmosphere; another project involves using drones to study these plumes.
Seven modeling teams will assess the potential effects of geoengineering on climate and ecosystems, particularly in developing countries housing approximately 85% of the global population. Additionally, five teams are tasked with addressing ethical and governance issues surrounding geoengineering, including the management and consensus-building for future developments.
