By Gloria Dickie
Yashas Raj and Jake Chapman are hunkered down in a basement laboratory at the University of Cambridge’s Department of Engineering—tinkering with a handheld nozzle they hope will one day be capable of shooting trillions of microscopic water droplets into the sky every second to brighten clouds over the Arctic Ocean. Boosting cloud reflectivity by adding the mist, they say, would cut the amount of sunlight reaching the water’s surface and slow the melting of Arctic sea ice.
The two Ph.D. students spend much of their time here in the Seawater Lab, mulling over revolutionary technologies that could curb Earth’s warming trajectory. Their work has drawn contempt from some campus peers who denounce such research aimed at manipulating the world’s climate over fears of unforeseen environmental consequences.
But such criticism has faded into background noise since the U.K. government last year allocated millions of dollars in funding to investigate climate geoengineering. It marked the first time a state funding body had invested significant money in geoengineering research, mainstreaming the once-taboo field and offering some validation to young students.
Raj and Chapman are part of a growing wave of Gen Z scientists and engineers across the world pursuing higher education in climate geoengineering, grasping for a feeling of agency as they inherit the woes wrought by older generations. “It’s daunting. We’re just 24-year-olds, and the engineering is going to be done by us,” said Raj, originally from Boston, now 25. “We have to build something and test it in the real world.”
The U.K.’s Advanced Research and Invention Agency (ARIA) has allotted 56.8 million British pounds ($76 million) for 21 research teams at global institutions to study climate geoengineering. Notably, nearly half of the ARIA funding will support small-scale field trials—the most contentious area of geoengineering research—to be rolled out over the next three years.
The public money, including another 10 million pounds ($13.4 million) from the U.K.’s Natural Environment Research Council, provides a heavy counterweight to controversial private startups, including the U.S. and Israeli-based Stardust Solutions and California’s Make Sunsets. These companies are working to commercialize stratospheric aerosol injection, a geoengineering technique that involves releasing reflective particles into the upper atmosphere to deflect some of the sun’s heat away from Earth.
Cambridge’s Centre for Climate Repair, housed in the same building where Stephen Hawking developed his theories on radiation, was first established in 2019. Over the past six years, the university has supported 19 Ph.D. students and 16 postdoctoral researchers investigating interventions such as sea curtains that could shield melting glaciers in Antarctica; thickening sea ice in the Canadian Arctic by pumping up seawater from under the ice; and brightening clouds over Australia’s Great Barrier Reef and Arctic waters to reduce incoming solar radiation. The centre’s funding comes from the university, government grants and philanthropic foundations.
“Over the last year, things have changed a lot,” said engineer Shaun Fitzgerald, director of the Centre. “We haven’t had that government financial support before. It’s a signal, in a way. It’s not just firebrand, wacky people trying stuff. If a government research agency says, ‘Actually, we think these are sensible questions,’ then it helps to just normalize the conversation.”
Other academic institutions, too, have launched climate geoengineering initiatives, incorporating the niche field into curricula. Harvard University introduced its Solar Geoengineering Research Program in 2017 to reduce scientific uncertainties about geoengineering. In 2023, the University of Chicago established the Climate Systems Engineering Initiative as part of a broader push to bolster education on possible climate interventions, with $6 million in funding for research projects.
While academics can apply for external grants to support their research, “the difference now is that there are some places where universities—and maybe the University of Chicago is the most important single place—are actually putting up their own money and starting real programs themselves,” said geophysicist David Keith, the founding director of the Chicago initiative who previously researched geoengineering at Harvard.