Washington Post: "Private companies have raised millions to block the sun. What could go wrong?"
by Nicolás Rivero
Make Sunsets has released just over 240 pounds of sulfur dioxide this year — well short of the millions of tons a year it would take to change global temperatures. Reaching that scale would require thousands of flights per year from specialized planes and at least the quiet tolerance of governments deciding to look the other way, said Gernot Wagner, a climate economist at Columbia Business School and a co-author on the 2018 study on the costs of geoengineering.
“There is no Silicon Valley venture capitalist who is able to do this, full stop. Even the billionaire who has hundreds of billions of dollars is running out of money sooner or later,” Wagner said. “But there are dozens of countries out there whose military air force budget alone could cover this. That’s what I’m really, really worried about: Not every one of these countries might have a democratically elected government acting in the best interest of the planet.”
Quoted in: "Private companies have raised millions to block the sun. What could go wrong?" by Nicolás Rivero, Washington Post (3 December 2025).
