Efforts to fight climate change may soon extend into uncharted territory as the UK prepares to fund outdoor experiments designed to reflect sunlight away from Earth. This move, aimed at curbing global warming, involves controversial solar geoengineering techniques that could be authorized within weeks.
According to a report in The Telegraph, the government’s Advanced Research and Invention Agency (ARIA) will allocate £50 million to investigate and test sunlight reflection methods.
These outdoor trials are expected to include stratospheric aerosol injection and marine cloud brightening—both methods designed to deflect solar radiation back into space.
Professor Mark Symes, ARIA’s programme director, confirmed the initiative will proceed with tightly regulated experiments. “We have strong requirements around the length of time experiments can run for and their reversibility,” he said, emphasizing that no toxic substances would be released.
Stratospheric Aerosol Injection (SAI) involves dispersing fine particles, such as sulphur dioxide, into the upper atmosphere to mimic the cooling effects of volcanic eruptions. This method draws on natural precedents, such as the 2014 Icelandic eruption, which cooled the planet by increasing cloud reflectivity.
Marine Cloud Brightening (MCB) aims to increase the reflectivity of low-lying clouds by spraying them with sea salt particles. Observations of shipping lanes, where exhaust plumes have brightened clouds, have shown the technique’s potential to reduce surface temperatures.
Despite the scientific rationale, critics argue that solar geoengineering is a perilous gamble. Experts warn that altering atmospheric chemistry could lead to unintended and irreversible consequences.
A Rutgers University study highlighted a chilling risk: if solar geoengineering is abruptly stopped, global temperatures could spike up to ten times faster than usual, triggering ecological collapse.
“There are real dangers in suddenly stopping geoengineering,” said Professor Alan Robock, coauthor of the study. “Rapid warming would be a huge threat to biodiversity and the environment.”
