David Keith, a scientist at the University of Chicago, is working on a controversial idea to slow down climate change.
He wants to spray sulfur dioxide into the upper atmosphere, which would reflect sunlight back into space, cooling the Earth.
This approach, called stratospheric solar geoengineering, is highly debated because of the potential risks and uncertainties.
While it seems like science fiction, it's becoming increasingly relevant as the effects of global warming intensify.
