The British government is poised to approve a controversial set of experiments aimed at artificially cooling the planet by dimming the sun — a radical form of climate intervention known as solar geoengineering. Backed by £50 million in funding, the initiative will explore whether technologies such as aerosol injections into the stratosphere or cloud manipulation could help mitigate the impacts of global warming.
As The Times reports, the funding comes through the Advanced Research and Invention Agency (Aria), a government-backed body tasked with high-risk, high-reward scientific innovation. Aria, seen by many as the brainchild of former Downing Street adviser Dominic Cummings, has a total budget of £800 million over the next four years and is modeled after the U.S. agency DARPA — known for its role in pioneering the internet and autonomous military technologies.
The geoengineering techniques under review include:
- Stratospheric aerosol injection: Spraying tiny particles into the upper atmosphere to reflect some of the sun’s energy away from Earth. The idea is inspired by natural cooling events after volcanic eruptions.
- Marine cloud brightening: Increasing the reflectivity of low-altitude clouds by seeding them with sea salt, potentially cooling the planet by bouncing sunlight back into space.
- Cirrus cloud thinning: Reducing the heat-trapping effect of high-altitude clouds to allow more thermal radiation to escape into space.
While early computer models suggest these methods could offer relatively low-cost temperature reductions, scientists are wary. Concerns range from unintended weather disruptions to the risk of undermining urgent efforts to cut carbon emissions. Critics also warn that such measures may provide a false sense of security or encourage political inaction on greenhouse gases.
Still, proponents argue that research is essential to better understand the risks and benefits of planetary-scale climate interventions. Professor Mark Symes, who leads Aria’s geoengineering programme, confirmed that the work may include “small controlled outdoor experiments” and emphasizes that even if not implemented, the studies could provide critical insights into Earth’s climate systems — and possibly support future planetary terraforming.
A document published by Aria last year hinted at the long-term ambitions: “Through carefully considered engineering solutions, it may eventually be possible to actively and responsibly control the climate at a global scale.”
