The Plan to Dim the Sun Could Actually Work—and That May Be the Most Dangerous Part of All

Here’s what you’ll learn when you read this story:

• To counteract the warming effects of climate change, solar radiation modification (SRM)—once seen as a strategy of last resort—is getting increasing attention.
• A detailed simulation, funded by the U.K. government, investigated how the world might respond to a sudden rush to deploy technologies such as SRM.
• The final report detailed how the geopolitical situation soon devolved into a “geoengineering arms race.”

The world is warming—there’s no question about that. The National Oceanic and Atmospheric Administration (NOAA) reported that the period from June to August 2026 was the hottest on record in the contiguous U.S. in recorded history. Sweltering conditions throughout Europe caused the continent’s iconic rivers to run dry. A devastating flash flood triggered by rising temperatures stunned the world and killed nearly 1,500 people in Nepal. And an overheated Pacific Ocean is unleashing the most powerful El Niño in a millennium while many scientists declare that the future they’ve spent decades warning the world about has finally arrived.

“We are witnessing the rapid destabilization of the Earth’s climate system. This is no longer a warning for the future; it is a diagnosis of the present,” reads the opening lines of a 2026 State of the Climate report, released earlier this week in the journal BioScience. “Earth’s life-support systems are being pushed beyond stable limits, with changes unfolding faster than our ability to respond.”

As the popular saying goes, desperate times call for desperate measures, and one of these “desperate measures” is solar geoengineering, a series of complicated schemes aimed at intentionally reflecting the sun’s rays back into space to cool the planet. One such method to crank down Earth’s thermostat is a type of a solar radiation modification, or SRM, known as stratospheric aerosol injection. This idea is already backed by science, given that volcanoes regularly inject reflective sulfur dioxide particles into the atmosphere, thereby cooling the Earth. In 1991, for example, the eruption of Mount Pinatubo cooled the planet by one degree Fahrenheit and other eruptions throughout history have had even more profound climate impacts.

So, the thinking goes, why not just do that intentionally: pump the stratosphere with sulfur dioxide, reflect incoming solar radiation, and solve the climate crisis? Well, if that sounds too good to be true, that’s because it is. While sulfur dioxide would certainly cool the planet, it could also have many unforeseen consequences, including impacts on human health. The Solar Geoengineering Non-Use Initiative also notes that such a solution could push governments and industries to avoid addressing the root cause of climate change—fossil fuel emissions.

“It is also seen as raising profound questions of justice, legality, and political power, with many critics arguing that it could never be governed in a fair, inclusive, and effective manner over the long timescales deployment would require,” one blog post on the initiative’s website reads.

This fact was made painfully clear by a recent initiative, funded by the U.K. government, to simulate the political fallout of governments, industries, and startups rushing to develop geoengineering technologies to alleviate the worst outcomes of climate change. The project, called Exploring Geopolitical Tipping Points and Climate Cooling Strategies, asked scientists, former government officials, and military experts to gather at Queen Mary University of London to play competing nations and interests and see what, if anything, they could agree on.

The results weren’t pretty. One of the participants, who spoke with Wired after the simulations, said that the political situation quickly devolved into a “geoengineering arms race” with superpowers, such as the U.S. and China, jockeying to be in control of this literally world-changing technology. Within the simulation, the fossil fuel industry masqueraded as NGOs—one called itself the Climate Futures Cooperative—to sell geoengineering as an alternative to cutting emissions. Meanwhile, simulated threats of secret geoengineering experiments added fuel to the geopolitical fire. Almost immediately, climate concerns were overshadowed by strategic competition and state sovereignty issues.

“Multiple types of uncertainty hampered progress towards agreement,” the final report of the simulation exercise reads. “The most persistent and important of these uncertainties were: how to assess and trust information in a fraught political context; how to gauge the intentions of actors engaging with SRM; and how the continued emergence of SRM would influence existing relationships and dynamics between different actors, particularly states.”

So even if SRMs worked wonders (and somehow had no serious environmental or health impacts), the chances of implementing such a strategy on a global scale appears vanishingly thin. For now, cutting fossil fuel emissions remains the only proven way to slow the warming.